chore(release): v1.0.0

feat: proper windows support
2026-03-15 11:04:58 +01:00 · 2026-03-15 11:04:44 +01:00
72 changed files with 3415 additions and 1694 deletions
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -1,6 +1,6 @@
 module(
    name = "rules_bun",
-    version = "0.5.0",
+    version = "1.0.0",
 )

 # Core ruleset dependencies.
--- a/MODULE.bazel.lock
+++ b/MODULE.bazel.lock
@@ -192,8 +192,8 @@
  "moduleExtensions": {
    "//bun:extensions.bzl%bun": {
      "general": {
-        "bzlTransitiveDigest": "lzOUyaXDbkH922ruNkkwEF2cnI4m0XpzrOti0qypwtA=",
-        "usagesDigest": "iOEuN6Lhr5Bejh9GRDT3yaCI7umBsNZo5CLQSzt+tNQ=",
+        "bzlTransitiveDigest": "314UOH4dQIGBHGpxCwA7yzI++E2J3bjIc20m5MZhM7U=",
+        "usagesDigest": "F7vNx1FkssnJKNa2AZDuwHKkH7+IjJNX42lRAaJhhKE=",
        "recordedInputs": [
          "REPO_MAPPING:,bazel_tools bazel_tools"
        ],
@@ -283,8 +283,8 @@
    },
    "//bun:extensions.bzl%bun_install": {
      "general": {
-        "bzlTransitiveDigest": "lzOUyaXDbkH922ruNkkwEF2cnI4m0XpzrOti0qypwtA=",
-        "usagesDigest": "eD/dECSVWIFS/qMgEXZ6501CimKmsHt7yTIFPX4XdLo=",
+        "bzlTransitiveDigest": "314UOH4dQIGBHGpxCwA7yzI++E2J3bjIc20m5MZhM7U=",
+        "usagesDigest": "5mKuORKUFhw+/OMHQF0I8Ngq0GV2eqMaOTDmyqaQa8M=",
        "recordedInputs": [
          "REPO_MAPPING:,bazel_tools bazel_tools"
        ],
@@ -300,7 +300,7 @@
              "omit": [],
              "linker": "",
              "backend": "",
-              "ignore_scripts": false,
+              "ignore_scripts": true,
              "install_flags": [],
              "visible_repo_name": "script_test_vite_node_modules"
            }
@@ -316,7 +316,7 @@
              "omit": [],
              "linker": "",
              "backend": "",
-              "ignore_scripts": false,
+              "ignore_scripts": true,
              "install_flags": [],
              "visible_repo_name": "script_test_vite_monorepo_node_modules"
            }
@@ -332,7 +332,7 @@
              "omit": [],
              "linker": "",
              "backend": "",
-              "ignore_scripts": false,
+              "ignore_scripts": true,
              "install_flags": [],
              "visible_repo_name": "script_test_paraglide_monorepo_node_modules"
            }
@@ -348,7 +348,7 @@
              "omit": [],
              "linker": "",
              "backend": "",
-              "ignore_scripts": false,
+              "ignore_scripts": true,
              "install_flags": [],
              "visible_repo_name": "examples_vite_monorepo_node_modules"
            }
--- a/README.md
+++ b/README.md
@@ -24,6 +24,10 @@ This repository follows the standard Bazel ruleset layout:

 The public entrypoint for rule authors and users is `@rules_bun//bun:defs.bzl`.

+Runtime launcher targets from `bun_binary`, `bun_script`, `bun_test`,
+`bun_dev`, and `js_run_devserver` use native platform wrappers. Windows runtime
+support is native and does not require Git Bash or MSYS.
+
 ## Public API

 `rules_bun` exports these primary rules:
@@ -48,6 +52,22 @@ Reference documentation:
 - `bun_install` extension docs: [docs/bun_install.md](docs/bun_install.md)
 - Docs index: [docs/index.md](docs/index.md)

+## Hermeticity
+
+`rules_bun` now draws a sharp line between hermetic rule surfaces and local
+workflow helpers.
+
+- Hermetic build/test surfaces: `bun_build`, `bun_bundle`, `bun_compile`, `bun_test`
+- Runfiles-only executable surface: `bun_binary`
+- Reproducible but non-hermetic repository fetch surface: `bun_install`
+- Local workflow helpers: `bun_script`, `bun_dev`, `js_run_devserver`
+
+Strict defaults are enabled by default:
+
+- `bun_install` skips lifecycle scripts unless `ignore_scripts = False`
+- `bun_build`, `bun_bundle`, `bun_compile`, and `bun_test` require `install_mode = "disable"`
+- Runtime launchers do not inherit the host `PATH` unless `inherit_host_path = True`
+
 To refresh generated rule docs:

 ```bash
@@ -60,7 +80,7 @@ Release announcements should provide a copy-pasteable module snippet in the
 standard ruleset form:

 ```starlark
-bazel_dep(name = "rules_bun", version = "0.5.0")
+bazel_dep(name = "rules_bun", version = "1.0.0")
 ```

 Then add the Bun repositories and register the toolchains in `MODULE.bazel`:
@@ -104,9 +124,10 @@ bun_install_ext.install(
    name = "bun_deps",
    package_json = "//:package.json",
    bun_lockfile = "//:bun.lock",
-    # Optional: include extra install-time files or allow Bun to reuse the
-    # host HOME/cache.
+    # Optional: include extra install-time files.
    # install_inputs = ["//:.npmrc"],
+    # Optional non-hermetic opt-in:
+    # ignore_scripts = False,
    # isolated_home = False,
 )

@@ -198,8 +219,9 @@ bun_script(
 ```

 When `node_modules` is provided, executables from `node_modules/.bin` are added
-to `PATH`. This label typically comes from `bun_install`, which still produces a
-standard `node_modules/` directory.
+to the runtime `PATH`. The host `PATH` is not inherited unless
+`inherit_host_path = True`. This label typically comes from `bun_install`,
+which still produces a standard `node_modules/` directory.

 ### `bun_build` and `bun_compile`

--- a/2
+++ b/2
@@ -1,3 +1,3 @@
-0.5.0
+1.0.0
 stable
 0
--- a/bun/extensions.bzl
+++ b/bun/extensions.bzl
@@ -81,7 +81,7 @@ _install = tag_class(
        "omit": attr.string_list(),
        "linker": attr.string(),
        "backend": attr.string(),
-        "ignore_scripts": attr.bool(default = False),
+        "ignore_scripts": attr.bool(default = True),
        "install_flags": attr.string_list(),
    },
 )
--- a/docs/bun_install.md
+++ b/docs/bun_install.md
@@ -20,6 +20,21 @@ Unlike the build rules in [rules.md](rules.md), `bun_install` is not loaded from
 The generated repository can then be passed to rules such as `bun_script`,
 `bun_binary`, `bun_bundle`, and `bun_test`.

+## Hermeticity
+
+`bun_install` is a repository convenience rule, not a hermetic build action.
+It is intended to be reproducible from a checked-in lockfile and pinned Bun
+toolchain, but it still performs dependency fetching as part of repository
+materialization.
+
+Strict defaults now favor reproducibility:
+
+- `isolated_home = True`
+- `ignore_scripts = True`
+
+Set `ignore_scripts = False` only when you explicitly want lifecycle scripts to
+run during repository creation.
+
 ## Usage

 ```starlark
@@ -150,6 +165,9 @@ Examples include `hardlink`, `symlink`, and `copyfile`.
 Optional boolean controlling whether Bun skips lifecycle scripts in the project
 manifest.

+- `True` (default): skips lifecycle scripts for stricter, more reproducible installs
+- `False`: allows lifecycle scripts to run during repository creation
+
 ### `install_flags`

 Optional list of additional raw flags forwarded to `bun install`.
@@ -164,3 +182,5 @@ Optional list of additional raw flags forwarded to `bun install`.
  `package.json`.
 - Additional `install_inputs` must be files under the same package root as the
  selected `package_json`.
+- `bun_install` does not make the install step remotely hermetic; it makes the
+  generated repository stricter and more reproducible by default.
--- a/docs/index.md
+++ b/docs/index.md
@@ -17,6 +17,13 @@ Supporting material lives in:
 - [docs/rules.md](rules.md) for generated build rule reference
 - [docs/bun_install.md](bun_install.md) for `bun_install` extension docs

+## Hermeticity
+
+- Hermetic rule surfaces: `bun_build`, `bun_bundle`, `bun_compile`, `bun_test`
+- Runfiles-only executable surface: `bun_binary`
+- Reproducible but non-hermetic repository surface: `bun_install`
+- Local workflow helpers: `bun_script`, `bun_dev`, `js_run_devserver`
+
 ## Rule reference

 - [rules.md](rules.md)
--- a/docs/rules.md
+++ b/docs/rules.md
@@ -2,6 +2,18 @@

 Public API surface for Bun Bazel rules.

+## Hermeticity And Determinism
+
+- Hermetic rule surfaces: `bun_build`, `bun_bundle`, `bun_compile`, `bun_test`
+- Runfiles-only executable surface: `bun_binary`
+- Reproducible but non-hermetic repository surface: `bun_install`
+- Local workflow helpers: `bun_script`, `bun_dev`, `js_run_devserver`
+
+Strict defaults:
+
+- `bun_build`, `bun_bundle`, `bun_compile`, and `bun_test` require `install_mode = "disable"`
+- Runtime launchers do not inherit the host `PATH` unless `inherit_host_path = True`
+
 <a id="bun_binary"></a>

 ## bun_binary
@@ -28,7 +40,8 @@ Use this rule for non-test scripts and CLIs that should run via `bazel run`.
 | <a id="bun_binary-conditions"></a>conditions |  Custom package resolve conditions passed to Bun.   | List of strings | optional |  `[]`  |
 | <a id="bun_binary-entry_point"></a>entry_point |  Path to the main JS/TS file to execute.   | <a href="https://bazel.build/concepts/labels">Label</a> | required |  |
 | <a id="bun_binary-env_files"></a>env_files |  Additional environment files loaded with `--env-file`.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional |  `[]`  |
-| <a id="bun_binary-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages at runtime.   | String | optional |  `"disable"`  |
+| <a id="bun_binary-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages at runtime. Non-`disable` values are runtime opt-ins and are not hermetic.   | String | optional |  `"disable"`  |
+| <a id="bun_binary-inherit_host_path"></a>inherit_host_path |  If true, appends the host PATH after staged `node_modules/.bin` entries at runtime.   | Boolean | optional |  `False`  |
 | <a id="bun_binary-no_env_file"></a>no_env_file |  If true, disables Bun's automatic `.env` loading.   | Boolean | optional |  `False`  |
 | <a id="bun_binary-node_modules"></a>node_modules |  Optional label providing package files from a `node_modules` tree, typically produced by `bun_install`, in runfiles.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
 | <a id="bun_binary-preload"></a>preload |  Modules to preload with `--preload` before running the entry point.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional |  `[]`  |
@@ -82,7 +95,7 @@ may be requested with `metafile` and `metafile_md`.
 | <a id="bun_build-feature"></a>feature |  Repeated `--feature` values for dead-code elimination.   | List of strings | optional |  `[]`  |
 | <a id="bun_build-footer"></a>footer |  Optional bundle footer text.   | String | optional |  `""`  |
 | <a id="bun_build-format"></a>format |  Output module format.   | String | optional |  `"esm"`  |
-| <a id="bun_build-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while executing the build.   | String | optional |  `"disable"`  |
+| <a id="bun_build-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while executing the build. Hermetic builds require `\"disable\"`, and other values are rejected.   | String | optional |  `"disable"`  |
 | <a id="bun_build-jsx_factory"></a>jsx_factory |  Optional JSX factory override.   | String | optional |  `""`  |
 | <a id="bun_build-jsx_fragment"></a>jsx_fragment |  Optional JSX fragment override.   | String | optional |  `""`  |
 | <a id="bun_build-jsx_import_source"></a>jsx_import_source |  Optional JSX import source override.   | String | optional |  `""`  |
@@ -135,7 +148,7 @@ Each entry point produces one output JavaScript artifact.
 | <a id="bun_bundle-entry_points"></a>entry_points |  Entry files to bundle.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | required |  |
 | <a id="bun_bundle-external"></a>external |  Package names to treat as externals (not bundled).   | List of strings | optional |  `[]`  |
 | <a id="bun_bundle-format"></a>format |  Output module format.   | String | optional |  `"esm"`  |
-| <a id="bun_bundle-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages during bundling.   | String | optional |  `"disable"`  |
+| <a id="bun_bundle-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages during bundling. Hermetic bundles require `\"disable\"`, and other values are rejected.   | String | optional |  `"disable"`  |
 | <a id="bun_bundle-minify"></a>minify |  If true, minifies bundle output.   | Boolean | optional |  `False`  |
 | <a id="bun_bundle-node_modules"></a>node_modules |  Optional label providing package files from a `node_modules` tree, typically produced by `bun_install`, for package resolution.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
 | <a id="bun_bundle-sourcemap"></a>sourcemap |  If true, emits source maps.   | Boolean | optional |  `False`  |
@@ -194,7 +207,7 @@ Compiles a Bun program into a standalone executable with `bun build --compile`.
 | <a id="bun_compile-feature"></a>feature |  Repeated `--feature` values for dead-code elimination.   | List of strings | optional |  `[]`  |
 | <a id="bun_compile-footer"></a>footer |  Optional bundle footer text.   | String | optional |  `""`  |
 | <a id="bun_compile-format"></a>format |  Output module format.   | String | optional |  `"esm"`  |
-| <a id="bun_compile-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while executing the build.   | String | optional |  `"disable"`  |
+| <a id="bun_compile-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while executing the build. Hermetic compile actions require `\"disable\"`, and other values are rejected.   | String | optional |  `"disable"`  |
 | <a id="bun_compile-jsx_factory"></a>jsx_factory |  Optional JSX factory override.   | String | optional |  `""`  |
 | <a id="bun_compile-jsx_fragment"></a>jsx_fragment |  Optional JSX fragment override.   | String | optional |  `""`  |
 | <a id="bun_compile-jsx_import_source"></a>jsx_import_source |  Optional JSX import source override.   | String | optional |  `""`  |
@@ -251,7 +264,8 @@ watch/HMR plus optional full restarts on selected file changes.
 | <a id="bun_dev-conditions"></a>conditions |  Custom package resolve conditions passed to Bun.   | List of strings | optional |  `[]`  |
 | <a id="bun_dev-entry_point"></a>entry_point |  Path to the main JS/TS file to execute in dev mode.   | <a href="https://bazel.build/concepts/labels">Label</a> | required |  |
 | <a id="bun_dev-env_files"></a>env_files |  Additional environment files loaded with `--env-file`.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional |  `[]`  |
-| <a id="bun_dev-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages in dev mode.   | String | optional |  `"disable"`  |
+| <a id="bun_dev-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages in dev mode. This is a local workflow helper, not a hermetic execution surface.   | String | optional |  `"disable"`  |
+| <a id="bun_dev-inherit_host_path"></a>inherit_host_path |  If true, appends the host PATH after staged `node_modules/.bin` entries at runtime.   | Boolean | optional |  `False`  |
 | <a id="bun_dev-no_clear_screen"></a>no_clear_screen |  If true, disables terminal clearing on Bun reloads.   | Boolean | optional |  `False`  |
 | <a id="bun_dev-no_env_file"></a>no_env_file |  If true, disables Bun's automatic `.env` loading.   | Boolean | optional |  `False`  |
 | <a id="bun_dev-node_modules"></a>node_modules |  Optional label providing package files from a `node_modules` tree, typically produced by `bun_install`, in runfiles.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
@@ -294,7 +308,8 @@ declared in `package.json` and expect to run from the package directory with
 | <a id="bun_script-env_files"></a>env_files |  Additional environment files loaded with `--env-file`.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional |  `[]`  |
 | <a id="bun_script-execution_mode"></a>execution_mode |  How Bun should execute matching workspace scripts.   | String | optional |  `"single"`  |
 | <a id="bun_script-filters"></a>filters |  Workspace package filters passed via repeated `--filter` flags.   | List of strings | optional |  `[]`  |
-| <a id="bun_script-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while running the script.   | String | optional |  `"disable"`  |
+| <a id="bun_script-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while running the script. This is a local workflow helper, not a hermetic execution surface.   | String | optional |  `"disable"`  |
+| <a id="bun_script-inherit_host_path"></a>inherit_host_path |  If true, appends the host PATH after staged `node_modules/.bin` entries at runtime.   | Boolean | optional |  `False`  |
 | <a id="bun_script-no_env_file"></a>no_env_file |  If true, disables Bun's automatic `.env` loading.   | Boolean | optional |  `False`  |
 | <a id="bun_script-no_exit_on_error"></a>no_exit_on_error |  If true, Bun keeps running other workspace scripts when one fails.   | Boolean | optional |  `False`  |
 | <a id="bun_script-node_modules"></a>node_modules |  Optional label providing package files from a `node_modules` tree, typically produced by `bun_install`, in runfiles. Executables from `node_modules/.bin` are added to `PATH`, which is useful for scripts such as `vite`.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
@@ -340,7 +355,8 @@ Supports Bazel test filtering (`--test_filter`) and coverage integration.
 | <a id="bun_test-coverage"></a>coverage |  If true, always enables Bun coverage output.   | Boolean | optional |  `False`  |
 | <a id="bun_test-coverage_reporters"></a>coverage_reporters |  Repeated Bun coverage reporters such as `text` or `lcov`.   | List of strings | optional |  `[]`  |
 | <a id="bun_test-env_files"></a>env_files |  Additional environment files loaded with `--env-file`.   | <a href="https://bazel.build/concepts/labels">List of labels</a> | optional |  `[]`  |
-| <a id="bun_test-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while testing.   | String | optional |  `"disable"`  |
+| <a id="bun_test-install_mode"></a>install_mode |  Whether Bun may auto-install missing packages while testing. Hermetic tests require `\"disable\"`, and other values are rejected.   | String | optional |  `"disable"`  |
+| <a id="bun_test-inherit_host_path"></a>inherit_host_path |  If true, appends the host PATH after staged `node_modules/.bin` entries at runtime.   | Boolean | optional |  `False`  |
 | <a id="bun_test-max_concurrency"></a>max_concurrency |  Optional maximum number of concurrent tests.   | Integer | optional |  `0`  |
 | <a id="bun_test-no_env_file"></a>no_env_file |  If true, disables Bun's automatic `.env` loading.   | Boolean | optional |  `False`  |
 | <a id="bun_test-node_modules"></a>node_modules |  Optional label providing package files from a `node_modules` tree, typically produced by `bun_install`, in runfiles.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
@@ -411,6 +427,7 @@ the provided tool with any default arguments.
 | <a id="js_run_devserver-package_dir_hint"></a>package_dir_hint |  Optional package-relative directory hint when package_json is not supplied.   | String | optional |  `"."`  |
 | <a id="js_run_devserver-package_json"></a>package_json |  Optional package.json used to resolve the package working directory.   | <a href="https://bazel.build/concepts/labels">Label</a> | optional |  `None`  |
 | <a id="js_run_devserver-tool"></a>tool |  Executable target to launch as the dev server.   | <a href="https://bazel.build/concepts/labels">Label</a> | required |  |
+| <a id="js_run_devserver-inherit_host_path"></a>inherit_host_path |  If true, appends the host PATH after staged `node_modules/.bin` entries at runtime.   | Boolean | optional |  `False`  |
 | <a id="js_run_devserver-working_dir"></a>working_dir |  Working directory at runtime: Bazel runfiles workspace root or the resolved package directory.   | String | optional |  `"workspace"`  |


@@ -480,4 +497,3 @@ js_test(<a href="#js_test-name">name</a>, <a href="#js_test-entry_point">entry_p
 | <a id="js_test-entry_point"></a>entry_point |  <p align="center"> - </p>   |  `None` |
 | <a id="js_test-srcs"></a>srcs |  <p align="center"> - </p>   |  `None` |
 | <a id="js_test-kwargs"></a>kwargs |  <p align="center"> - </p>   |  none |
-
--- a/internal/BUILD.bazel
+++ b/internal/BUILD.bazel
@@ -15,6 +15,8 @@ exports_files([
    "js_compat.bzl",
    "js_library.bzl",
    "js_run_devserver.bzl",
+    "runtime_launcher.bzl",
+    "runtime_launcher.js",
    "workspace.bzl",
 ])

@@ -34,6 +36,8 @@ filegroup(
        "js_compat.bzl",
        "js_library.bzl",
        "js_run_devserver.bzl",
+        "runtime_launcher.bzl",
+        "runtime_launcher.js",
        "workspace.bzl",
    ],
    visibility = ["//visibility:public"],
@@ -59,6 +63,7 @@ bzl_library(
    deps = [
        ":bun_command_bzl",
        ":js_library_bzl",
+        ":runtime_launcher_bzl",
        ":workspace_bzl",
    ],
 )
@@ -84,6 +89,7 @@ bzl_library(
    srcs = ["bun_dev.bzl"],
    deps = [
        ":bun_command_bzl",
+        ":runtime_launcher_bzl",
        ":workspace_bzl",
    ],
 )
@@ -98,6 +104,7 @@ bzl_library(
    srcs = ["bun_script.bzl"],
    deps = [
        ":bun_command_bzl",
+        ":runtime_launcher_bzl",
        ":workspace_bzl",
    ],
 )
@@ -108,6 +115,7 @@ bzl_library(
    deps = [
        ":bun_command_bzl",
        ":js_library_bzl",
+        ":runtime_launcher_bzl",
        ":workspace_bzl",
    ],
 )
@@ -133,10 +141,16 @@ bzl_library(
    srcs = ["js_run_devserver.bzl"],
    deps = [
        ":js_library_bzl",
+        ":runtime_launcher_bzl",
        ":workspace_bzl",
    ],
 )

+bzl_library(
+    name = "runtime_launcher_bzl",
+    srcs = ["runtime_launcher.bzl"],
+)
+
 bzl_library(
    name = "workspace_bzl",
    srcs = ["workspace.bzl"],
--- a/internal/bun_binary.bzl
+++ b/internal/bun_binary.bzl
@@ -1,8 +1,9 @@
 """Rule for running JS/TS scripts with Bun."""

-load("//internal:bun_command.bzl", "append_shell_flag", "append_shell_flag_files", "append_shell_flag_values", "append_shell_install_mode", "append_shell_raw_flags", "render_shell_array", "shell_quote")
+load("//internal:bun_command.bzl", "append_flag", "append_flag_values", "append_install_mode", "append_raw_flags")
 load("//internal:js_library.bzl", "collect_js_runfiles")
-load("//internal:workspace.bzl", "create_bun_workspace_info", "render_workspace_setup", "workspace_runfiles")
+load("//internal:runtime_launcher.bzl", "declare_runtime_wrapper", "runfiles_path", "runtime_launcher_attrs", "write_launcher_spec")
+load("//internal:workspace.bzl", "create_bun_workspace_info", "workspace_runfiles")

 def _bun_binary_impl(ctx):
    toolchain = ctx.toolchains["//bun:toolchain_type"]
@@ -15,58 +16,55 @@ def _bun_binary_impl(ctx):
        primary_file = entry_point,
    )

-    launcher_lines = [render_shell_array("bun_args", ["--bun", "run"])]
-    append_shell_install_mode(launcher_lines, "bun_args", ctx.attr.install_mode)
-    append_shell_flag_files(launcher_lines, "bun_args", "--preload", ctx.files.preload)
-    append_shell_flag_files(launcher_lines, "bun_args", "--env-file", ctx.files.env_files)
-    append_shell_flag(launcher_lines, "bun_args", "--no-env-file", ctx.attr.no_env_file)
-    append_shell_flag(launcher_lines, "bun_args", "--smol", ctx.attr.smol)
-    append_shell_flag_values(launcher_lines, "bun_args", "--conditions", ctx.attr.conditions)
-    append_shell_raw_flags(launcher_lines, "bun_args", ctx.attr.run_flags)
-    launcher_lines.append('bun_args+=("${primary_source}")')
-    for arg in ctx.attr.args:
-        launcher_lines.append("bun_args+=(%s)" % shell_quote(arg))
+    argv = ["--bun", "run"]
+    append_install_mode(argv, ctx.attr.install_mode)
+    append_flag(argv, "--no-env-file", ctx.attr.no_env_file)
+    append_flag(argv, "--smol", ctx.attr.smol)
+    append_flag_values(argv, "--conditions", ctx.attr.conditions)
+    append_raw_flags(argv, ctx.attr.run_flags)

-    command = """
-trap cleanup_runtime_workspace EXIT
-cd "${runtime_exec_dir}"
-__BUN_ARGS__
-exec "${bun_bin}" "${bun_args[@]}" "$@"
-""".replace("__BUN_ARGS__", "\n".join(launcher_lines))
-
-    launcher = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.write(
-        output = launcher,
-        is_executable = True,
-        content = render_workspace_setup(
-            bun_short_path = bun_bin.short_path,
-            install_metadata_short_path = workspace_info.install_metadata_file.short_path if workspace_info.install_metadata_file else "",
-            primary_source_short_path = entry_point.short_path,
-            working_dir_mode = ctx.attr.working_dir,
-        ) + command,
-    )
+    spec_file = write_launcher_spec(ctx, {
+        "version": 1,
+        "kind": "bun_run",
+        "bun_short_path": runfiles_path(bun_bin),
+        "primary_source_short_path": runfiles_path(entry_point),
+        "package_json_short_path": "",
+        "install_metadata_short_path": runfiles_path(workspace_info.install_metadata_file) if workspace_info.install_metadata_file else "",
+        "install_repo_runfiles_path": workspace_info.install_repo_runfiles_path,
+        "node_modules_roots": workspace_info.node_modules_roots,
+        "package_dir_hint": workspace_info.package_dir_hint,
+        "working_dir_mode": ctx.attr.working_dir,
+        "inherit_host_path": ctx.attr.inherit_host_path,
+        "argv": argv,
+        "args": ctx.attr.args,
+        "passthrough_args": True,
+        "tool_short_path": "",
+        "restart_on": [],
+        "watch_mode": "",
+        "reporter": "",
+        "coverage": False,
+        "coverage_reporters": [],
+        "preload_short_paths": [runfiles_path(file) for file in ctx.files.preload],
+        "env_file_short_paths": [runfiles_path(file) for file in ctx.files.env_files],
+        "test_short_paths": [],
+    })
+    launcher = declare_runtime_wrapper(ctx, bun_bin, spec_file)

    return [
        workspace_info,
        DefaultInfo(
-            executable = launcher,
+            executable = launcher.executable,
            runfiles = workspace_runfiles(
                ctx,
                workspace_info,
-                direct_files = [launcher],
+                direct_files = [launcher.executable, launcher.runner, spec_file],
                transitive_files = dep_runfiles,
            ),
        ),
    ]

-
-bun_binary = rule(
-    implementation = _bun_binary_impl,
-    doc = """Runs a JS/TS entry point with Bun as an executable target.
-
-Use this rule for non-test scripts and CLIs that should run via `bazel run`.
-""",
-    attrs = {
+_BUN_BINARY_ATTRS = runtime_launcher_attrs()
+_BUN_BINARY_ATTRS.update({
    "entry_point": attr.label(
        mandatory = True,
        allow_single_file = [".js", ".ts", ".jsx", ".tsx", ".mjs", ".cjs"],
@@ -114,7 +112,19 @@ Use this rule for non-test scripts and CLIs that should run via `bazel run`.
        values = ["workspace", "entry_point"],
        doc = "Working directory at runtime: `workspace` root or nearest `entry_point` ancestor containing `.env`/`package.json`.",
    ),
-    },
+    "inherit_host_path": attr.bool(
+        default = False,
+        doc = "If true, appends the host PATH after staged node_modules/.bin entries at runtime.",
+    ),
+})
+
+bun_binary = rule(
+    implementation = _bun_binary_impl,
+    doc = """Runs a JS/TS entry point with Bun as an executable target.
+
+Use this rule for non-test scripts and CLIs that should run via `bazel run`.
+""",
+    attrs = _BUN_BINARY_ATTRS,
    executable = True,
    toolchains = ["//bun:toolchain_type"],
 )
--- a/internal/bun_build_support.bzl
+++ b/internal/bun_build_support.bzl
@@ -3,6 +3,74 @@
 load("//internal:bun_command.bzl", "add_flag", "add_flag_value", "add_flag_values", "add_install_mode", "add_raw_flags")
 load("//internal:js_library.bzl", "collect_js_sources")

+_STAGED_BUILD_RUNNER = """import { spawnSync } from "node:child_process";
+import { cpSync, mkdirSync, mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, resolve } from "node:path";
+
+const [, , manifestPath, ...buildArgs] = process.argv;
+const execroot = process.cwd();
+const stageDir = mkdtempSync(resolve(tmpdir(), "rules_bun_build-"));
+
+function rewriteArgPath(flag, value) {
+  return `${flag}=${resolve(execroot, value)}`;
+}
+
+try {
+  for (const relpath of readFileSync(manifestPath, "utf8").split(/\\r?\\n/)) {
+    if (!relpath) {
+      continue;
+    }
+    const src = resolve(execroot, relpath);
+    const dest = resolve(stageDir, relpath);
+    mkdirSync(dirname(dest), { recursive: true });
+    cpSync(src, dest, { dereference: true, force: true, recursive: true });
+  }
+
+  const forwardedArgs = [];
+  for (let index = 0; index < buildArgs.length; index += 1) {
+    const arg = buildArgs[index];
+    if ((arg === "--outdir" || arg === "--outfile") && index + 1 < buildArgs.length) {
+      forwardedArgs.push(arg, resolve(execroot, buildArgs[index + 1]));
+      index += 1;
+      continue;
+    }
+    if (arg.startsWith("--metafile=")) {
+      forwardedArgs.push(rewriteArgPath("--metafile", arg.slice("--metafile=".length)));
+      continue;
+    }
+    if (arg.startsWith("--metafile-md=")) {
+      forwardedArgs.push(rewriteArgPath("--metafile-md", arg.slice("--metafile-md=".length)));
+      continue;
+    }
+    forwardedArgs.push(arg);
+  }
+
+  const result = spawnSync(process.execPath, forwardedArgs, {
+    cwd: stageDir,
+    stdio: "inherit",
+  });
+  if (result.error) {
+    throw result.error;
+  }
+  process.exit(typeof result.status === "number" ? result.status : 1);
+} finally {
+  rmSync(stageDir, { recursive: true, force: true });
+}
+"""
+
+def sort_files_by_short_path(files):
+    files_by_path = {}
+    short_paths = []
+    for file in files:
+        files_by_path[file.short_path] = file
+        short_paths.append(file.short_path)
+    return [files_by_path[short_path] for short_path in sorted(short_paths)]
+
+def validate_hermetic_install_mode(attr, rule_name):
+    if getattr(attr, "install_mode", "disable") != "disable":
+        fail("{} requires install_mode = \"disable\" for hermetic execution".format(rule_name))
+
 def infer_entry_point_root(entries):
    if not entries:
        return None
@@ -112,3 +180,29 @@ def add_bun_compile_flags(args, attr, compile_executable = None):
    add_flag_value(args, "--windows-version", getattr(attr, "windows_version", None))
    add_flag_value(args, "--windows-description", getattr(attr, "windows_description", None))
    add_flag_value(args, "--windows-copyright", getattr(attr, "windows_copyright", None))
+
+def declare_staged_bun_build_action(ctx, bun_bin, build_args, build_inputs, outputs, mnemonic, progress_message, name_suffix):
+    sorted_inputs = sort_files_by_short_path(build_inputs.to_list())
+    input_manifest = ctx.actions.declare_file(ctx.label.name + name_suffix + ".inputs")
+    runner = ctx.actions.declare_file(ctx.label.name + name_suffix + "_runner.js")
+
+    ctx.actions.write(
+        output = input_manifest,
+        content = "".join([file.path + "\n" for file in sorted_inputs]),
+    )
+    ctx.actions.write(
+        output = runner,
+        content = _STAGED_BUILD_RUNNER,
+    )
+
+    ctx.actions.run(
+        executable = bun_bin,
+        arguments = ["--bun", runner.path, input_manifest.path, build_args],
+        inputs = depset(
+            direct = [input_manifest, runner],
+            transitive = [build_inputs],
+        ),
+        outputs = outputs,
+        mnemonic = mnemonic,
+        progress_message = progress_message,
+    )
--- a/internal/bun_bundle.bzl
+++ b/internal/bun_bundle.bzl
@@ -1,21 +1,30 @@
 """Rule for bundling JS/TS sources with Bun."""

-load("//internal:bun_build_support.bzl", "add_bun_build_common_flags", "bun_build_transitive_inputs")
+load("//internal:bun_build_support.bzl", "add_bun_build_common_flags", "bun_build_transitive_inputs", "declare_staged_bun_build_action", "sort_files_by_short_path", "validate_hermetic_install_mode")


 def _output_name(target_name, entry):
-    stem = entry.basename.rsplit(".", 1)[0]
-    return "{}__{}.js".format(target_name, stem)
+    stem = entry.short_path.rsplit(".", 1)[0]
+    sanitized = stem.replace("\\", "_").replace("/", "_").replace("-", "_").replace(".", "_").replace("@", "at_")
+    sanitized = sanitized.replace("__", "_").replace("__", "_").replace("__", "_")
+    sanitized = sanitized.strip("_")
+    if not sanitized:
+        sanitized = entry.basename.rsplit(".", 1)[0]
+    return "{}__{}.js".format(target_name, sanitized)


 def _bun_bundle_impl(ctx):
+    validate_hermetic_install_mode(ctx.attr, "bun_bundle")
+
    toolchain = ctx.toolchains["//bun:toolchain_type"]
    bun_bin = toolchain.bun.bun_bin
+    entry_points = sort_files_by_short_path(ctx.files.entry_points)
+    data_files = sort_files_by_short_path(ctx.files.data)

    transitive_inputs = bun_build_transitive_inputs(ctx)

    outputs = []
-    for entry in ctx.files.entry_points:
+    for entry in entry_points:
        output = ctx.actions.declare_file(_output_name(ctx.label.name, entry))
        outputs.append(output)

@@ -27,16 +36,18 @@ def _bun_bundle_impl(ctx):
        args.add(output.path)
        args.add(entry.path)

-        ctx.actions.run(
-            executable = bun_bin,
-            arguments = [args],
-            inputs = depset(
-                direct = [entry] + ctx.files.data,
+        declare_staged_bun_build_action(
+            ctx,
+            bun_bin,
+            args,
+            depset(
+                direct = [entry] + data_files,
                transitive = transitive_inputs,
            ),
            outputs = [output],
            mnemonic = "BunBundle",
            progress_message = "Bundling {} with Bun".format(entry.short_path),
+            name_suffix = "_bundle_{}".format(output.basename.rsplit(".", 1)[0]),
        )

    return [DefaultInfo(files = depset(outputs))]
@@ -67,7 +78,7 @@ Each entry point produces one output JavaScript artifact.
        "install_mode": attr.string(
            default = "disable",
            values = ["disable", "auto", "fallback", "force"],
-            doc = "Whether Bun may auto-install missing packages during bundling.",
+            doc = "Whether Bun may auto-install missing packages during bundling. Hermetic bundle actions require `disable`; other values are rejected.",
        ),
        "target": attr.string(
            default = "browser",
--- a/internal/bun_command.bzl
+++ b/internal/bun_command.bzl
@@ -82,3 +82,32 @@ def add_install_mode(args, install_mode):
        args.add("--no-install")
    elif install_mode in ["fallback", "force"]:
        add_flag_value(args, "--install", install_mode)
+
+def append_arg(values, value):
+    values.append(str(value))
+
+def append_flag(values, flag, enabled):
+    if enabled:
+        append_arg(values, flag)
+
+def append_flag_value(values, flag, value):
+    if value == None:
+        return
+    if type(value) == type("") and not value:
+        return
+    append_arg(values, flag)
+    append_arg(values, value)
+
+def append_flag_values(values, flag, items):
+    for item in items:
+        append_flag_value(values, flag, item)
+
+def append_raw_flags(values, items):
+    for item in items:
+        append_arg(values, item)
+
+def append_install_mode(values, install_mode):
+    if install_mode == "disable":
+        append_arg(values, "--no-install")
+    elif install_mode in ["fallback", "force"]:
+        append_flag_value(values, "--install", install_mode)
--- a/internal/bun_compile.bzl
+++ b/internal/bun_compile.bzl
@@ -1,10 +1,14 @@
 """Rules for Bun build outputs and standalone executables."""

-load("//internal:bun_build_support.bzl", "add_bun_build_common_flags", "add_bun_compile_flags", "bun_build_transitive_inputs", "infer_entry_point_root")
+load("//internal:bun_build_support.bzl", "add_bun_build_common_flags", "add_bun_compile_flags", "bun_build_transitive_inputs", "declare_staged_bun_build_action", "infer_entry_point_root", "sort_files_by_short_path", "validate_hermetic_install_mode")

 def _bun_build_impl(ctx):
+    validate_hermetic_install_mode(ctx.attr, "bun_build")
+
    toolchain = ctx.toolchains["//bun:toolchain_type"]
    bun_bin = toolchain.bun.bun_bin
+    entry_points = sort_files_by_short_path(ctx.files.entry_points)
+    data_files = sort_files_by_short_path(ctx.files.data)
    output_dir = ctx.actions.declare_directory(ctx.label.name)
    metafile = None
    if ctx.attr.metafile:
@@ -14,24 +18,20 @@ def _bun_build_impl(ctx):
        metafile_md = ctx.actions.declare_file(ctx.label.name + ".meta.md")
    build_root = ctx.attr.root
    if not build_root:
-        build_root = infer_entry_point_root(ctx.files.entry_points)
+        build_root = infer_entry_point_root(entry_points)
    transitive_inputs = bun_build_transitive_inputs(ctx)
    build_inputs = depset(
-        direct = ctx.files.entry_points + ctx.files.data,
+        direct = entry_points + data_files,
        transitive = transitive_inputs,
    )
-    input_manifest = ctx.actions.declare_file(ctx.label.name + ".inputs")
-    runner = ctx.actions.declare_file(ctx.label.name + "_runner.sh")

-    args = ctx.actions.args()
-    args.add(input_manifest.path)
-    args.add(bun_bin.path)
-    args.add("--bun")
-    args.add("build")
-    add_bun_build_common_flags(args, ctx.attr, metafile = metafile, metafile_md = metafile_md, root = build_root)
-    args.add("--outdir")
-    args.add(output_dir.path)
-    args.add_all(ctx.files.entry_points)
+    build_args = ctx.actions.args()
+    build_args.add("--bun")
+    build_args.add("build")
+    add_bun_build_common_flags(build_args, ctx.attr, metafile = metafile, metafile_md = metafile_md, root = build_root)
+    build_args.add("--outdir")
+    build_args.add(output_dir.path)
+    build_args.add_all(entry_points)

    outputs = [output_dir]
    if metafile:
@@ -39,87 +39,27 @@ def _bun_build_impl(ctx):
    if metafile_md:
        outputs.append(metafile_md)

-    ctx.actions.write(
-        output = input_manifest,
-        content = "".join([file.path + "\n" for file in build_inputs.to_list()]),
-    )
-
-    ctx.actions.write(
-        output = runner,
-        is_executable = True,
-        content = """#!/usr/bin/env bash
-set -euo pipefail
-
-manifest="$1"
-execroot="$(pwd -P)"
-bun_bin="$2"
-if [[ "${bun_bin}" != /* ]]; then
-  bun_bin="${execroot}/${bun_bin}"
-fi
-shift 2
-
-stage_dir="$(mktemp -d "${TMPDIR:-/tmp}/rules_bun_build.XXXXXX")"
-cleanup() {
-  rm -rf "${stage_dir}"
-}
-trap cleanup EXIT
-
-while IFS= read -r relpath; do
-  if [[ -z "${relpath}" ]]; then
-    continue
-  fi
-  src="${execroot}/${relpath}"
-  dest="${stage_dir}/${relpath}"
-  mkdir -p "$(dirname "${dest}")"
-  cp -L "${src}" "${dest}"
-done < "${manifest}"
-
-forwarded_args=()
-while (($#)); do
-  case "$1" in
-    --outdir)
-      forwarded_args+=("$1" "${execroot}/$2")
-      shift 2
-      ;;
-    --metafile=*)
-      forwarded_args+=("--metafile=${execroot}/${1#--metafile=}")
-      shift
-      ;;
-    --metafile-md=*)
-      forwarded_args+=("--metafile-md=${execroot}/${1#--metafile-md=}")
-      shift
-      ;;
-    *)
-      forwarded_args+=("$1")
-      shift
-      ;;
-  esac
-done
-
-cd "${stage_dir}"
-exec "${bun_bin}" "${forwarded_args[@]}"
-""",
-    )
-
-    ctx.actions.run(
-        executable = runner,
-        arguments = [args],
-        inputs = depset(
-            direct = [input_manifest, bun_bin],
-            transitive = [build_inputs],
-        ),
+    declare_staged_bun_build_action(
+        ctx,
+        bun_bin,
+        build_args,
+        build_inputs,
        outputs = outputs,
        mnemonic = "BunBuild",
        progress_message = "Building {} with Bun".format(ctx.label.name),
+        name_suffix = "_build",
    )

    return [DefaultInfo(files = depset(outputs))]

 def _bun_compile_impl(ctx):
+    validate_hermetic_install_mode(ctx.attr, "bun_compile")
+
    toolchain = ctx.toolchains["//bun:toolchain_type"]
    bun_bin = toolchain.bun.bun_bin
    output = ctx.actions.declare_file(ctx.label.name)
    compile_executable = ctx.file.compile_executable
+    data_files = sort_files_by_short_path(ctx.files.data)

    args = ctx.actions.args()
    args.add("--bun")
@@ -130,20 +70,22 @@ def _bun_compile_impl(ctx):
    args.add(output.path)
    args.add(ctx.file.entry_point.path)

-    direct_inputs = [ctx.file.entry_point] + ctx.files.data
+    direct_inputs = [ctx.file.entry_point] + data_files
    if compile_executable:
        direct_inputs.append(compile_executable)

-    ctx.actions.run(
-        executable = bun_bin,
-        arguments = [args],
-        inputs = depset(
+    declare_staged_bun_build_action(
+        ctx,
+        bun_bin,
+        args,
+        depset(
            direct = direct_inputs,
            transitive = bun_build_transitive_inputs(ctx),
        ),
        outputs = [output],
        mnemonic = "BunCompile",
        progress_message = "Compiling {} with Bun".format(ctx.file.entry_point.short_path),
+        name_suffix = "_compile",
    )

    return [
@@ -167,7 +109,7 @@ _COMMON_BUILD_ATTRS = {
    "install_mode": attr.string(
        default = "disable",
        values = ["disable", "auto", "fallback", "force"],
-        doc = "Whether Bun may auto-install missing packages while executing the build.",
+        doc = "Whether Bun may auto-install missing packages while executing the build. Hermetic build actions require `disable`; other values are rejected.",
    ),
    "target": attr.string(
        default = "browser",
--- a/internal/bun_dev.bzl
+++ b/internal/bun_dev.bzl
@@ -1,7 +1,8 @@
 """Rule for running JS/TS scripts with Bun in watch mode for development."""

-load("//internal:bun_command.bzl", "append_shell_flag", "append_shell_flag_files", "append_shell_flag_values", "append_shell_install_mode", "append_shell_raw_flags", "render_shell_array", "shell_quote")
-load("//internal:workspace.bzl", "create_bun_workspace_info", "render_workspace_setup", "workspace_runfiles")
+load("//internal:bun_command.bzl", "append_flag", "append_flag_values", "append_install_mode", "append_raw_flags")
+load("//internal:runtime_launcher.bzl", "declare_runtime_wrapper", "runfiles_path", "runtime_launcher_attrs", "write_launcher_spec")
+load("//internal:workspace.bzl", "create_bun_workspace_info", "workspace_runfiles")

 def _bun_dev_impl(ctx):
    toolchain = ctx.toolchains["//bun:toolchain_type"]
@@ -13,142 +14,55 @@ def _bun_dev_impl(ctx):
        primary_file = entry_point,
    )

-    restart_watch_paths = "\n".join([path.short_path for path in ctx.files.restart_on])
-    launcher_lines = [render_shell_array("bun_args", ["--bun", "run"])]
-    append_shell_install_mode(launcher_lines, "bun_args", ctx.attr.install_mode)
-    append_shell_flag_files(launcher_lines, "bun_args", "--preload", ctx.files.preload)
-    append_shell_flag_files(launcher_lines, "bun_args", "--env-file", ctx.files.env_files)
-    append_shell_flag(launcher_lines, "bun_args", "--no-env-file", ctx.attr.no_env_file)
-    append_shell_flag(launcher_lines, "bun_args", "--smol", ctx.attr.smol)
-    append_shell_flag_values(launcher_lines, "bun_args", "--conditions", ctx.attr.conditions)
-    append_shell_flag(launcher_lines, "bun_args", "--no-clear-screen", ctx.attr.no_clear_screen)
-    append_shell_raw_flags(launcher_lines, "bun_args", ctx.attr.run_flags)
-    launcher_lines.append('bun_args+=("${primary_source}")')
-    for arg in ctx.attr.args:
-        launcher_lines.append("bun_args+=(%s)" % shell_quote(arg))
+    argv = ["--bun", "run"]
+    append_install_mode(argv, ctx.attr.install_mode)
+    append_flag(argv, "--no-env-file", ctx.attr.no_env_file)
+    append_flag(argv, "--smol", ctx.attr.smol)
+    append_flag_values(argv, "--conditions", ctx.attr.conditions)
+    append_flag(argv, "--no-clear-screen", ctx.attr.no_clear_screen)
+    append_raw_flags(argv, ctx.attr.run_flags)

-    command = """
-__BUN_ARGS__
-watch_mode="__WATCH_MODE__"
-if [[ "${watch_mode}" == "hot" ]]; then
-    bun_args+=("--hot")
-else
-    bun_args+=("--watch")
-fi
-
-if [[ __RESTART_COUNT__ -eq 0 ]]; then
-    trap cleanup_runtime_workspace EXIT
-    cd "${runtime_exec_dir}"
-    exec "${bun_bin}" "${bun_args[@]}" "$@"
-fi
-
-readarray -t restart_paths <<'EOF_RESTART_PATHS'
-__RESTART_PATHS__
-EOF_RESTART_PATHS
-
-file_mtime() {
-    local path="$1"
-    if stat -f '%m' "${path}" >/dev/null 2>&1; then
-        stat -f '%m' "${path}"
-        return 0
-    fi
-    stat -c '%Y' "${path}"
-}
-
-declare -A mtimes
-for rel in "${restart_paths[@]}"; do
-    path="${runfiles_dir}/_main/${rel}"
-    if [[ -e "${path}" ]]; then
-        mtimes["${rel}"]="$(file_mtime "${path}")"
-    else
-        mtimes["${rel}"]="missing"
-    fi
-done
-
-child_pid=""
-restart_child() {
-    if [[ -n "${child_pid}" ]] && kill -0 "${child_pid}" 2>/dev/null; then
-        kill "${child_pid}"
-        wait "${child_pid}" || true
-    fi
-
-    (
-        cd "${runtime_exec_dir}"
-        exec "${bun_bin}" "${bun_args[@]}" "$@"
-    ) &
-    child_pid=$!
-}
-
-cleanup() {
-    if [[ -n "${child_pid}" ]] && kill -0 "${child_pid}" 2>/dev/null; then
-        kill "${child_pid}"
-        wait "${child_pid}" || true
-    fi
-    cleanup_runtime_workspace
-}
-
-trap cleanup EXIT INT TERM
-
-restart_child "$@"
-
-while true; do
-    sleep 1
-    changed=0
-    for rel in "${restart_paths[@]}"; do
-        path="${runfiles_dir}/_main/${rel}"
-        if [[ -e "${path}" ]]; then
-            current="$(file_mtime "${path}")"
-        else
-            current="missing"
-        fi
-        if [[ "${current}" != "${mtimes[${rel}]}" ]]; then
-            mtimes["${rel}"]="${current}"
-            changed=1
-        fi
-    done
-    if [[ "${changed}" -eq 1 ]]; then
-        restart_child "$@"
-    fi
-done
-""".replace("__WATCH_MODE__", ctx.attr.watch_mode).replace(
-        "__RESTART_COUNT__",
-        str(len(ctx.files.restart_on)),
-    ).replace(
-        "__RESTART_PATHS__",
-        restart_watch_paths,
-    ).replace(
-        "__BUN_ARGS__",
-        "\n".join(launcher_lines),
-    )
-
-    launcher = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.write(
-        output = launcher,
-        is_executable = True,
-        content = render_workspace_setup(
-            bun_short_path = bun_bin.short_path,
-            install_metadata_short_path = workspace_info.install_metadata_file.short_path if workspace_info.install_metadata_file else "",
-            primary_source_short_path = entry_point.short_path,
-            working_dir_mode = ctx.attr.working_dir,
-        ) + command,
-    )
+    spec_file = write_launcher_spec(ctx, {
+        "version": 1,
+        "kind": "bun_run",
+        "bun_short_path": runfiles_path(bun_bin),
+        "primary_source_short_path": runfiles_path(entry_point),
+        "package_json_short_path": "",
+        "install_metadata_short_path": runfiles_path(workspace_info.install_metadata_file) if workspace_info.install_metadata_file else "",
+        "install_repo_runfiles_path": workspace_info.install_repo_runfiles_path,
+        "node_modules_roots": workspace_info.node_modules_roots,
+        "package_dir_hint": workspace_info.package_dir_hint,
+        "working_dir_mode": ctx.attr.working_dir,
+        "inherit_host_path": ctx.attr.inherit_host_path,
+        "argv": argv,
+        "args": ctx.attr.args,
+        "passthrough_args": True,
+        "tool_short_path": "",
+        "restart_on": [runfiles_path(file) for file in ctx.files.restart_on],
+        "watch_mode": ctx.attr.watch_mode,
+        "reporter": "",
+        "coverage": False,
+        "coverage_reporters": [],
+        "preload_short_paths": [runfiles_path(file) for file in ctx.files.preload],
+        "env_file_short_paths": [runfiles_path(file) for file in ctx.files.env_files],
+        "test_short_paths": [],
+    })
+    launcher = declare_runtime_wrapper(ctx, bun_bin, spec_file)

    return [
        workspace_info,
        DefaultInfo(
-            executable = launcher,
-            runfiles = workspace_runfiles(ctx, workspace_info, direct_files = [launcher]),
+            executable = launcher.executable,
+            runfiles = workspace_runfiles(
+                ctx,
+                workspace_info,
+                direct_files = [launcher.executable, launcher.runner, spec_file],
+            ),
        ),
    ]

-bun_dev = rule(
-    implementation = _bun_dev_impl,
-    doc = """Runs a JS/TS entry point in Bun development watch mode.
-
-This rule is intended for local dev loops (`bazel run`) and supports Bun
-watch/HMR plus optional full restarts on selected file changes.
-""",
-    attrs = {
+_BUN_DEV_ATTRS = runtime_launcher_attrs()
+_BUN_DEV_ATTRS.update({
    "entry_point": attr.label(
        mandatory = True,
        allow_single_file = [".js", ".ts", ".jsx", ".tsx", ".mjs", ".cjs"],
@@ -206,7 +120,21 @@ watch/HMR plus optional full restarts on selected file changes.
        values = ["workspace", "entry_point"],
        doc = "Working directory at runtime: `workspace` root or nearest `entry_point` ancestor containing `.env`/`package.json`.",
    ),
-    },
+    "inherit_host_path": attr.bool(
+        default = False,
+        doc = "If true, appends the host PATH after staged node_modules/.bin entries at runtime.",
+    ),
+})
+
+bun_dev = rule(
+    implementation = _bun_dev_impl,
+    doc = """Runs a JS/TS entry point in Bun development watch mode.
+
+This rule is intended for local dev loops (`bazel run`) and supports Bun
+watch/HMR plus optional full restarts on selected file changes. It is a local
+workflow helper rather than a hermetic build rule.
+""",
+    attrs = _BUN_DEV_ATTRS,
    executable = True,
    toolchains = ["//bun:toolchain_type"],
 )
--- a/internal/bun_install.bzl
+++ b/internal/bun_install.bzl
@@ -205,8 +205,14 @@ def _materialize_workspace_packages(repository_ctx, package_json):
            workspace_packages[relative_dir] = package_name if type(package_name) == type("") else ""

    package_dirs = sorted(workspace_packages.keys())
+    package_names_by_dir = {}
+    for package_dir in package_dirs:
+        package_name = workspace_packages[package_dir]
+        if package_name:
+            package_names_by_dir[package_dir] = package_name
    return struct(
        package_dirs = package_dirs,
+        package_names_by_dir = package_names_by_dir,
        package_names = [workspace_packages[package_dir] for package_dir in package_dirs if workspace_packages[package_dir]],
    )

@@ -381,8 +387,10 @@ stderr:
        "node_modules/.rules_bun/install.json",
        json.encode({
            "bun_lockfile": lockfile_name,
+            "install_root_rel_dir": ".",
            "package_json": "package.json",
            "workspace_package_dirs": workspace_packages.package_dirs,
+            "workspace_package_names_by_dir": workspace_packages.package_names_by_dir,
        }) + "\n",
    )

@@ -409,7 +417,7 @@ bun_install_repository = repository_rule(
        "omit": attr.string_list(),
        "linker": attr.string(),
        "backend": attr.string(),
-        "ignore_scripts": attr.bool(default = False),
+        "ignore_scripts": attr.bool(default = True),
        "install_flags": attr.string_list(),
        "visible_repo_name": attr.string(),
        "bun_linux_x64": attr.label(default = "@bun_linux_x64//:bun-linux-x64/bun", allow_single_file = True),
@@ -430,7 +438,7 @@ def bun_install(
        omit = [],
        linker = "",
        backend = "",
-        ignore_scripts = False,
+        ignore_scripts = True,
        install_flags = []):
    """Create an external repository containing installed node_modules.

--- a/internal/bun_script.bzl
+++ b/internal/bun_script.bzl
@@ -1,8 +1,8 @@
 """Rule for running package.json scripts with Bun."""

-load("//internal:bun_command.bzl", "append_shell_flag", "append_shell_flag_files", "append_shell_flag_value", "append_shell_flag_values", "append_shell_install_mode", "append_shell_raw_flags", "render_shell_array", "shell_quote")
-load("//internal:workspace.bzl", "create_bun_workspace_info", "render_workspace_setup", "workspace_runfiles")
-
+load("//internal:bun_command.bzl", "append_flag", "append_flag_value", "append_flag_values", "append_install_mode", "append_raw_flags")
+load("//internal:runtime_launcher.bzl", "declare_runtime_wrapper", "runfiles_path", "runtime_launcher_attrs", "write_launcher_spec")
+load("//internal:workspace.bzl", "create_bun_workspace_info", "workspace_runfiles")

 def _bun_script_impl(ctx):
    toolchain = ctx.toolchains["//bun:toolchain_type"]
@@ -16,68 +16,63 @@ def _bun_script_impl(ctx):
        primary_file = package_json,
    )

-    launcher_lines = [render_shell_array("bun_args", ["--bun", "run"])]
-    append_shell_install_mode(launcher_lines, "bun_args", ctx.attr.install_mode)
-    append_shell_flag_files(launcher_lines, "bun_args", "--preload", ctx.files.preload)
-    append_shell_flag_files(launcher_lines, "bun_args", "--env-file", ctx.files.env_files)
-    append_shell_flag(launcher_lines, "bun_args", "--no-env-file", ctx.attr.no_env_file)
-    append_shell_flag(launcher_lines, "bun_args", "--smol", ctx.attr.smol)
-    append_shell_flag_values(launcher_lines, "bun_args", "--conditions", ctx.attr.conditions)
-    append_shell_flag(launcher_lines, "bun_args", "--workspaces", ctx.attr.workspaces)
-    append_shell_flag_values(launcher_lines, "bun_args", "--filter", ctx.attr.filters)
+    argv = ["--bun", "run"]
+    append_install_mode(argv, ctx.attr.install_mode)
+    append_flag(argv, "--no-env-file", ctx.attr.no_env_file)
+    append_flag(argv, "--smol", ctx.attr.smol)
+    append_flag_values(argv, "--conditions", ctx.attr.conditions)
+    append_flag(argv, "--workspaces", ctx.attr.workspaces)
+    append_flag_values(argv, "--filter", ctx.attr.filters)
    if ctx.attr.execution_mode == "parallel":
-        append_shell_flag(launcher_lines, "bun_args", "--parallel", True)
+        append_flag(argv, "--parallel", True)
    elif ctx.attr.execution_mode == "sequential":
-        append_shell_flag(launcher_lines, "bun_args", "--sequential", True)
-    append_shell_flag(launcher_lines, "bun_args", "--no-exit-on-error", ctx.attr.no_exit_on_error)
-    append_shell_flag_value(launcher_lines, "bun_args", "--shell", ctx.attr.shell)
-    append_shell_flag(launcher_lines, "bun_args", "--silent", ctx.attr.silent)
-    append_shell_raw_flags(launcher_lines, "bun_args", ctx.attr.run_flags)
-    launcher_lines.append('bun_args+=(%s)' % shell_quote(ctx.attr.script))
-    for arg in ctx.attr.args:
-        launcher_lines.append("bun_args+=(%s)" % shell_quote(arg))
+        append_flag(argv, "--sequential", True)
+    append_flag(argv, "--no-exit-on-error", ctx.attr.no_exit_on_error)
+    append_flag_value(argv, "--shell", ctx.attr.shell)
+    append_flag(argv, "--silent", ctx.attr.silent)
+    append_raw_flags(argv, ctx.attr.run_flags)

-    command = """
-trap cleanup_runtime_workspace EXIT
-cd "${runtime_exec_dir}"
-__BUN_ARGS__
-exec "${bun_bin}" "${bun_args[@]}" "$@"
-""".replace("__BUN_ARGS__", "\n".join(launcher_lines))
-
-    launcher = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.write(
-        output = launcher,
-        is_executable = True,
-        content = render_workspace_setup(
-            bun_short_path = bun_bin.short_path,
-            package_dir_hint = package_json.dirname or ".",
-            package_json_short_path = package_json.short_path,
-            primary_source_short_path = package_json.short_path,
-            install_metadata_short_path = workspace_info.install_metadata_file.short_path if workspace_info.install_metadata_file else "",
-            working_dir_mode = ctx.attr.working_dir,
-        ) + command,
-    )
+    spec_file = write_launcher_spec(ctx, {
+        "version": 1,
+        "kind": "bun_run",
+        "bun_short_path": runfiles_path(bun_bin),
+        "primary_source_short_path": "",
+        "package_json_short_path": runfiles_path(package_json),
+        "install_metadata_short_path": runfiles_path(workspace_info.install_metadata_file) if workspace_info.install_metadata_file else "",
+        "install_repo_runfiles_path": workspace_info.install_repo_runfiles_path,
+        "node_modules_roots": workspace_info.node_modules_roots,
+        "package_dir_hint": package_json.dirname or ".",
+        "working_dir_mode": ctx.attr.working_dir,
+        "inherit_host_path": ctx.attr.inherit_host_path,
+        "argv": argv,
+        "args": [ctx.attr.script] + ctx.attr.args,
+        "passthrough_args": True,
+        "tool_short_path": "",
+        "restart_on": [],
+        "watch_mode": "",
+        "reporter": "",
+        "coverage": False,
+        "coverage_reporters": [],
+        "preload_short_paths": [runfiles_path(file) for file in ctx.files.preload],
+        "env_file_short_paths": [runfiles_path(file) for file in ctx.files.env_files],
+        "test_short_paths": [],
+    })
+    launcher = declare_runtime_wrapper(ctx, bun_bin, spec_file)

    return [
        workspace_info,
        DefaultInfo(
-            executable = launcher,
-            runfiles = workspace_runfiles(ctx, workspace_info, direct_files = [launcher]),
+            executable = launcher.executable,
+            runfiles = workspace_runfiles(
+                ctx,
+                workspace_info,
+                direct_files = [launcher.executable, launcher.runner, spec_file],
+            ),
        ),
    ]

-
-bun_script = rule(
-    implementation = _bun_script_impl,
-    doc = """Runs a named `package.json` script with Bun as an executable target.
-
-Use this rule to expose existing package scripts such as `dev`, `build`, or
-`check` via `bazel run` without adding wrapper shell scripts. This is a good fit
-for Vite-style workflows, where scripts like `vite dev` or `vite build` are
-declared in `package.json` and expect to run from the package directory with
-`node_modules/.bin` available on `PATH`.
-""",
-    attrs = {
+_BUN_SCRIPT_ATTRS = runtime_launcher_attrs()
+_BUN_SCRIPT_ATTRS.update({
    "script": attr.string(
        mandatory = True,
        doc = "Name of the `package.json` script to execute via `bun run <script>`.",
@@ -151,7 +146,23 @@ declared in `package.json` and expect to run from the package directory with
        values = ["workspace", "package"],
        doc = "Working directory at runtime: Bazel runfiles `workspace` root or the directory containing `package.json`. The default `package` mode matches tools such as Vite that resolve config and assets relative to the package directory.",
    ),
-    },
+    "inherit_host_path": attr.bool(
+        default = False,
+        doc = "If true, appends the host PATH after staged node_modules/.bin entries at runtime.",
+    ),
+})
+
+bun_script = rule(
+    implementation = _bun_script_impl,
+    doc = """Runs a named `package.json` script with Bun as an executable target.
+
+Use this rule to expose existing package scripts such as `dev`, `build`, or
+`check` via `bazel run` without adding wrapper shell scripts. This is a good fit
+for Vite-style workflows, where scripts like `vite dev` or `vite build` are
+declared in `package.json` and expect to run from the package directory. This
+is a local workflow helper rather than a hermetic build rule.
+""",
+    attrs = _BUN_SCRIPT_ATTRS,
    executable = True,
    toolchains = ["//bun:toolchain_type"],
 )
--- a/internal/bun_test.bzl
+++ b/internal/bun_test.bzl
@@ -1,11 +1,14 @@
 """Rule for running test suites with Bun."""

-load("//internal:bun_command.bzl", "append_shell_flag", "append_shell_flag_files", "append_shell_flag_value", "append_shell_flag_values", "append_shell_install_mode", "append_shell_raw_flags", "render_shell_array", "shell_quote")
+load("//internal:bun_command.bzl", "append_flag", "append_flag_value", "append_install_mode", "append_raw_flags")
 load("//internal:js_library.bzl", "collect_js_runfiles")
-load("//internal:workspace.bzl", "create_bun_workspace_info", "render_workspace_setup", "workspace_runfiles")
-
+load("//internal:runtime_launcher.bzl", "declare_runtime_wrapper", "runfiles_path", "runtime_launcher_attrs", "write_launcher_spec")
+load("//internal:workspace.bzl", "create_bun_workspace_info", "workspace_runfiles")

 def _bun_test_impl(ctx):
+    if ctx.attr.install_mode != "disable":
+        fail("bun_test requires install_mode = \"disable\" for hermetic test execution")
+
    toolchain = ctx.toolchains["//bun:toolchain_type"]
    bun_bin = toolchain.bun.bun_bin
    primary_file = ctx.files.srcs[0]
@@ -16,97 +19,66 @@ def _bun_test_impl(ctx):
        primary_file = primary_file,
    )

-    launcher_lines = [render_shell_array("bun_args", ["--bun", "test"])]
-    append_shell_install_mode(launcher_lines, "bun_args", ctx.attr.install_mode)
-    append_shell_flag_files(launcher_lines, "bun_args", "--preload", ctx.files.preload)
-    append_shell_flag_files(launcher_lines, "bun_args", "--env-file", ctx.files.env_files)
-    append_shell_flag(launcher_lines, "bun_args", "--no-env-file", ctx.attr.no_env_file)
-    append_shell_flag(launcher_lines, "bun_args", "--smol", ctx.attr.smol)
-    append_shell_flag_value(launcher_lines, "bun_args", "--timeout", str(ctx.attr.timeout_ms) if ctx.attr.timeout_ms > 0 else None)
-    append_shell_flag(launcher_lines, "bun_args", "--update-snapshots", ctx.attr.update_snapshots)
-    append_shell_flag_value(launcher_lines, "bun_args", "--rerun-each", str(ctx.attr.rerun_each) if ctx.attr.rerun_each > 0 else None)
-    append_shell_flag_value(launcher_lines, "bun_args", "--retry", str(ctx.attr.retry) if ctx.attr.retry > 0 else None)
-    append_shell_flag(launcher_lines, "bun_args", "--todo", ctx.attr.todo)
-    append_shell_flag(launcher_lines, "bun_args", "--only", ctx.attr.only)
-    append_shell_flag(launcher_lines, "bun_args", "--pass-with-no-tests", ctx.attr.pass_with_no_tests)
-    append_shell_flag(launcher_lines, "bun_args", "--concurrent", ctx.attr.concurrent)
-    append_shell_flag(launcher_lines, "bun_args", "--randomize", ctx.attr.randomize)
-    append_shell_flag_value(launcher_lines, "bun_args", "--seed", str(ctx.attr.seed) if ctx.attr.seed > 0 else None)
-    append_shell_flag_value(launcher_lines, "bun_args", "--bail", str(ctx.attr.bail) if ctx.attr.bail > 0 else None)
-    append_shell_flag_value(launcher_lines, "bun_args", "--max-concurrency", str(ctx.attr.max_concurrency) if ctx.attr.max_concurrency > 0 else None)
-    append_shell_raw_flags(launcher_lines, "bun_args", ctx.attr.test_flags)
-    launcher_lines.append('coverage_requested="0"')
-    launcher_lines.append('coverage_dir=""')
-    launcher_lines.append('if [[ "${COVERAGE_DIR:-}" != "" ]]; then')
-    launcher_lines.append('  coverage_requested="1"')
-    launcher_lines.append('  coverage_dir="${COVERAGE_DIR}"')
-    launcher_lines.append('elif [[ "%s" == "1" ]]; then' % ("1" if ctx.attr.coverage else "0"))
-    launcher_lines.append('  coverage_requested="1"')
-    launcher_lines.append('  coverage_dir="${TEST_UNDECLARED_OUTPUTS_DIR:-${runtime_workspace}/coverage}"')
-    launcher_lines.append('fi')
-    launcher_lines.append('if [[ "${coverage_requested}" == "1" ]]; then')
-    launcher_lines.append('  bun_args+=("--coverage")')
-    launcher_lines.append('  bun_args+=("--coverage-dir" "${coverage_dir}")')
-    if ctx.attr.coverage_reporters:
-        for reporter in ctx.attr.coverage_reporters:
-            launcher_lines.append('  bun_args+=("--coverage-reporter" %s)' % shell_quote(reporter))
-    else:
-        launcher_lines.append('  if [[ "${COVERAGE_DIR:-}" != "" ]]; then')
-        launcher_lines.append('    bun_args+=("--coverage-reporter" "lcov")')
-        launcher_lines.append('  fi')
-    launcher_lines.append('fi')
-    launcher_lines.append('if [[ -n "${TESTBRIDGE_TEST_ONLY:-}" ]]; then')
-    launcher_lines.append('  bun_args+=("--test-name-pattern" "${TESTBRIDGE_TEST_ONLY}")')
-    launcher_lines.append('fi')
-    if ctx.attr.reporter == "junit":
-        launcher_lines.append('reporter_out="${XML_OUTPUT_FILE:-${runtime_workspace}/junit.xml}"')
-        launcher_lines.append('bun_args+=("--reporter" "junit" "--reporter-outfile" "${reporter_out}")')
-    elif ctx.attr.reporter == "dots":
-        launcher_lines.append('bun_args+=("--reporter" "dots")')
-    for src in ctx.files.srcs:
-        launcher_lines.append("bun_args+=(%s)" % shell_quote(src.short_path))
-    for arg in ctx.attr.args:
-        launcher_lines.append("bun_args+=(%s)" % shell_quote(arg))
+    argv = ["--bun", "test"]
+    append_install_mode(argv, ctx.attr.install_mode)
+    append_flag(argv, "--no-env-file", ctx.attr.no_env_file)
+    append_flag(argv, "--smol", ctx.attr.smol)
+    append_flag_value(argv, "--timeout", str(ctx.attr.timeout_ms) if ctx.attr.timeout_ms > 0 else None)
+    append_flag(argv, "--update-snapshots", ctx.attr.update_snapshots)
+    append_flag_value(argv, "--rerun-each", str(ctx.attr.rerun_each) if ctx.attr.rerun_each > 0 else None)
+    append_flag_value(argv, "--retry", str(ctx.attr.retry) if ctx.attr.retry > 0 else None)
+    append_flag(argv, "--todo", ctx.attr.todo)
+    append_flag(argv, "--only", ctx.attr.only)
+    append_flag(argv, "--pass-with-no-tests", ctx.attr.pass_with_no_tests)
+    append_flag(argv, "--concurrent", ctx.attr.concurrent)
+    append_flag(argv, "--randomize", ctx.attr.randomize)
+    append_flag_value(argv, "--seed", str(ctx.attr.seed) if ctx.attr.seed > 0 else None)
+    append_flag_value(argv, "--bail", str(ctx.attr.bail) if ctx.attr.bail > 0 else None)
+    append_flag_value(argv, "--max-concurrency", str(ctx.attr.max_concurrency) if ctx.attr.max_concurrency > 0 else None)
+    append_raw_flags(argv, ctx.attr.test_flags)

-    command = """
-trap cleanup_runtime_workspace EXIT
-cd "${runtime_workspace}"
-__BUN_ARGS__
-exec "${bun_bin}" "${bun_args[@]}" "$@"
-""".replace("__BUN_ARGS__", "\n".join(launcher_lines))
+    spec_file = write_launcher_spec(ctx, {
+        "version": 1,
+        "kind": "bun_test",
+        "bun_short_path": runfiles_path(bun_bin),
+        "primary_source_short_path": runfiles_path(primary_file),
+        "package_json_short_path": "",
+        "install_metadata_short_path": runfiles_path(workspace_info.install_metadata_file) if workspace_info.install_metadata_file else "",
+        "install_repo_runfiles_path": workspace_info.install_repo_runfiles_path,
+        "node_modules_roots": workspace_info.node_modules_roots,
+        "package_dir_hint": workspace_info.package_dir_hint,
+        "working_dir_mode": "workspace",
+        "inherit_host_path": ctx.attr.inherit_host_path,
+        "argv": argv,
+        "args": ctx.attr.args,
+        "passthrough_args": True,
+        "tool_short_path": "",
+        "restart_on": [],
+        "watch_mode": "",
+        "reporter": ctx.attr.reporter,
+        "coverage": ctx.attr.coverage,
+        "coverage_reporters": ctx.attr.coverage_reporters,
+        "preload_short_paths": [runfiles_path(file) for file in ctx.files.preload],
+        "env_file_short_paths": [runfiles_path(file) for file in ctx.files.env_files],
+        "test_short_paths": [runfiles_path(file) for file in ctx.files.srcs],
+    })
+    launcher = declare_runtime_wrapper(ctx, bun_bin, spec_file)

-    launcher = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.write(
-        output = launcher,
-        is_executable = True,
-        content = render_workspace_setup(
-            bun_short_path = bun_bin.short_path,
-            install_metadata_short_path = workspace_info.install_metadata_file.short_path if workspace_info.install_metadata_file else "",
-            primary_source_short_path = primary_file.short_path,
-            working_dir_mode = "workspace",
-        ) + command,
-    )
    return [
        workspace_info,
        DefaultInfo(
-            executable = launcher,
+            executable = launcher.executable,
            runfiles = workspace_runfiles(
                ctx,
                workspace_info,
-                direct_files = [launcher],
+                direct_files = [launcher.executable, launcher.runner, spec_file],
                transitive_files = dep_runfiles,
            ),
        ),
    ]

-
-bun_test = rule(
-    implementation = _bun_test_impl,
-    doc = """Runs Bun tests as a Bazel test target.
-
-Supports Bazel test filtering (`--test_filter`) and coverage integration.
-""",
-    attrs = {
+_BUN_TEST_ATTRS = runtime_launcher_attrs()
+_BUN_TEST_ATTRS.update({
    "srcs": attr.label_list(
        mandatory = True,
        allow_files = [".js", ".ts", ".jsx", ".tsx", ".mjs", ".cjs"],
@@ -206,7 +178,21 @@ Supports Bazel test filtering (`--test_filter`) and coverage integration.
    "test_flags": attr.string_list(
        doc = "Additional raw flags forwarded to `bun test` before the test source list.",
    ),
-    },
+    "inherit_host_path": attr.bool(
+        default = False,
+        doc = "If true, appends the host PATH after staged node_modules/.bin entries at runtime.",
+    ),
+})
+
+bun_test = rule(
+    implementation = _bun_test_impl,
+    doc = """Runs Bun tests as a Bazel test target.
+
+Supports Bazel test filtering (`--test_filter`) and coverage integration. Tests
+run with strict install-mode semantics and do not inherit the host PATH unless
+explicitly requested.
+""",
+    attrs = _BUN_TEST_ATTRS,
    test = True,
    toolchains = ["//bun:toolchain_type"],
 )
--- a/internal/js_run_devserver.bzl
+++ b/internal/js_run_devserver.bzl
@@ -1,10 +1,8 @@
 """Compatibility rule for running an executable target as a dev server."""

 load("//internal:js_library.bzl", "collect_js_runfiles")
-load("//internal:workspace.bzl", "create_bun_workspace_info", "render_workspace_setup", "workspace_runfiles")
-
-def _shell_quote(value):
-    return "'" + value.replace("'", "'\"'\"'") + "'"
+load("//internal:runtime_launcher.bzl", "declare_runtime_wrapper", "runfiles_path", "runtime_launcher_attrs", "write_launcher_spec")
+load("//internal:workspace.bzl", "create_bun_workspace_info", "workspace_runfiles")

 def _js_run_devserver_impl(ctx):
    toolchain = ctx.toolchains["//bun:toolchain_type"]
@@ -21,51 +19,48 @@ def _js_run_devserver_impl(ctx):
        extra_files = ctx.files.data + [bun_bin, tool_default_info.files_to_run.executable],
    )

-    tool_workspace = ctx.attr.tool.label.workspace_name or "_main"
-    tool_path = "{}/{}".format(tool_workspace, tool_default_info.files_to_run.executable.short_path)
-    default_args = " ".join([_shell_quote(arg) for arg in ctx.attr.args])
-
-    launcher = ctx.actions.declare_file(ctx.label.name)
-    ctx.actions.write(
-        output = launcher,
-        is_executable = True,
-        content = render_workspace_setup(
-            bun_short_path = bun_bin.short_path,
-            install_metadata_short_path = workspace_info.install_metadata_file.short_path if workspace_info.install_metadata_file else "",
-            primary_source_short_path = package_json.short_path if package_json else tool_default_info.files_to_run.executable.short_path,
-            package_json_short_path = package_json.short_path if package_json else "",
-            package_dir_hint = ctx.attr.package_dir_hint,
-            working_dir_mode = ctx.attr.working_dir,
-        ) + """
-trap cleanup_runtime_workspace EXIT
-cd "${runtime_exec_dir}"
-tool="${runfiles_dir}/__TOOL_SHORT_PATH__"
-exec "${tool}" __DEFAULT_ARGS__ "$@"
-""".replace("__TOOL_SHORT_PATH__", tool_path).replace("__DEFAULT_ARGS__", default_args),
-    )
+    spec_file = write_launcher_spec(ctx, {
+        "version": 1,
+        "kind": "tool_exec",
+        "bun_short_path": runfiles_path(bun_bin),
+        "primary_source_short_path": runfiles_path(package_json) if package_json else runfiles_path(tool_default_info.files_to_run.executable),
+        "package_json_short_path": runfiles_path(package_json) if package_json else "",
+        "install_metadata_short_path": runfiles_path(workspace_info.install_metadata_file) if workspace_info.install_metadata_file else "",
+        "install_repo_runfiles_path": workspace_info.install_repo_runfiles_path,
+        "node_modules_roots": workspace_info.node_modules_roots,
+        "package_dir_hint": ctx.attr.package_dir_hint,
+        "working_dir_mode": ctx.attr.working_dir,
+        "inherit_host_path": ctx.attr.inherit_host_path,
+        "argv": [],
+        "args": ctx.attr.args,
+        "passthrough_args": True,
+        "tool_short_path": runfiles_path(tool_default_info.files_to_run.executable),
+        "restart_on": [],
+        "watch_mode": "",
+        "reporter": "",
+        "coverage": False,
+        "coverage_reporters": [],
+        "preload_short_paths": [],
+        "env_file_short_paths": [],
+        "test_short_paths": [],
+    })
+    launcher = declare_runtime_wrapper(ctx, bun_bin, spec_file)

    return [
        workspace_info,
        DefaultInfo(
-            executable = launcher,
+            executable = launcher.executable,
            runfiles = workspace_runfiles(
                ctx,
                workspace_info,
-                direct_files = [launcher, tool_default_info.files_to_run.executable],
+                direct_files = [launcher.executable, launcher.runner, spec_file, tool_default_info.files_to_run.executable],
                transitive_files = dep_runfiles,
            ).merge(tool_default_info.default_runfiles),
        ),
    ]

-js_run_devserver = rule(
-    implementation = _js_run_devserver_impl,
-    doc = """Runs an executable target from a staged JS workspace.
-
-This is a Bun-backed compatibility adapter for `rules_js`-style devserver
-targets. It stages the same runtime workspace as the Bun rules, then executes
-the provided tool with any default arguments.
-""",
-    attrs = {
+_JS_RUN_DEVSERVER_ATTRS = runtime_launcher_attrs()
+_JS_RUN_DEVSERVER_ATTRS.update({
    "tool": attr.label(
        mandatory = True,
        executable = True,
@@ -95,7 +90,22 @@ the provided tool with any default arguments.
        values = ["workspace", "package"],
        doc = "Working directory at runtime: Bazel runfiles workspace root or the resolved package directory.",
    ),
-    },
+    "inherit_host_path": attr.bool(
+        default = False,
+        doc = "If true, appends the host PATH after staged node_modules/.bin entries at runtime.",
+    ),
+})
+
+js_run_devserver = rule(
+    implementation = _js_run_devserver_impl,
+    doc = """Runs an executable target from a staged JS workspace.
+
+This is a Bun-backed compatibility adapter for `rules_js`-style devserver
+targets. It stages the same runtime workspace as the Bun rules, then executes
+the provided tool with any default arguments. It is intended for local
+development workflows rather than hermetic build execution.
+""",
+    attrs = _JS_RUN_DEVSERVER_ATTRS,
    executable = True,
    toolchains = ["//bun:toolchain_type"],
 )
--- a/internal/runtime_launcher.bzl
+++ b/internal/runtime_launcher.bzl
@@ -0,0 +1,173 @@
+"""Shared launcher spec and OS-native wrapper helpers for runtime rules."""
+
+_RUNTIME_LAUNCHER = Label("//internal:runtime_launcher.js")
+_WINDOWS_CONSTRAINT = Label("@platforms//os:windows")
+
+_POSIX_WRAPPER_TEMPLATE = """#!/bin/sh
+set -eu
+
+self="$0"
+runfiles_dir="${RUNFILES_DIR:-}"
+manifest="${RUNFILES_MANIFEST_FILE:-}"
+
+if [ -n "${runfiles_dir}" ] && [ -d "${runfiles_dir}" ]; then
+  :
+elif [ -n "${manifest}" ] && [ -f "${manifest}" ]; then
+  :
+elif [ -d "${self}.runfiles" ]; then
+  runfiles_dir="${self}.runfiles"
+elif [ -f "${self}.runfiles_manifest" ]; then
+  manifest="${self}.runfiles_manifest"
+elif [ -f "${self}.exe.runfiles_manifest" ]; then
+  manifest="${self}.exe.runfiles_manifest"
+else
+  echo "rules_bun: unable to locate runfiles for ${self}" >&2
+  exit 1
+fi
+
+rlocation() {
+  path="$1"
+  if [ -n "${runfiles_dir}" ]; then
+    printf '%s\\n' "${runfiles_dir}/${path}"
+    return 0
+  fi
+
+  result=""
+  while IFS= read -r line; do
+    case "${line}" in
+      "${path} "*)
+        result="${line#${path} }"
+        break
+        ;;
+    esac
+  done < "${manifest}"
+  if [ -z "${result}" ]; then
+    echo "rules_bun: missing runfile ${path}" >&2
+    exit 1
+  fi
+  printf '%s\\n' "${result}"
+}
+
+bun_bin="$(rlocation "__BUN_RUNFILES_PATH__")"
+runner="$(rlocation "__RUNNER_RUNFILES_PATH__")"
+spec="$(rlocation "__SPEC_RUNFILES_PATH__")"
+
+export RULES_BUN_LAUNCHER_PATH="${self}"
+if [ -n "${runfiles_dir}" ]; then
+  export RULES_BUN_RUNFILES_DIR="${runfiles_dir}"
+fi
+if [ -n "${manifest}" ]; then
+  export RULES_BUN_RUNFILES_MANIFEST="${manifest}"
+fi
+
+exec "${bun_bin}" --bun "${runner}" "${spec}" "$@"
+"""
+
+_CMD_WRAPPER_TEMPLATE = """@echo off
+setlocal
+
+set "SELF=%~f0"
+set "RUNFILES_DIR_VALUE=%RUNFILES_DIR%"
+set "RUNFILES_MANIFEST_VALUE=%RUNFILES_MANIFEST_FILE%"
+
+if defined RUNFILES_DIR_VALUE if exist "%RUNFILES_DIR_VALUE%" goto have_runfiles
+if defined RUNFILES_MANIFEST_VALUE if exist "%RUNFILES_MANIFEST_VALUE%" goto have_runfiles
+if exist "%SELF%.runfiles" (
+  set "RUNFILES_DIR_VALUE=%SELF%.runfiles"
+  goto have_runfiles
+)
+if exist "%SELF%.runfiles_manifest" (
+  set "RUNFILES_MANIFEST_VALUE=%SELF%.runfiles_manifest"
+  goto have_runfiles
+)
+if exist "%~dpn0.runfiles_manifest" (
+  set "RUNFILES_MANIFEST_VALUE=%~dpn0.runfiles_manifest"
+  goto have_runfiles
+)
+
+echo rules_bun: unable to locate runfiles for "%SELF%" 1>&2
+exit /b 1
+
+:have_runfiles
+call :rlocation "__BUN_RUNFILES_PATH__" BUN_BIN || exit /b 1
+call :rlocation "__RUNNER_RUNFILES_PATH__" RUNNER || exit /b 1
+call :rlocation "__SPEC_RUNFILES_PATH__" SPEC || exit /b 1
+
+set "RULES_BUN_LAUNCHER_PATH=%SELF%"
+if defined RUNFILES_DIR_VALUE (
+  set "RULES_BUN_RUNFILES_DIR=%RUNFILES_DIR_VALUE%"
+) else (
+  set "RULES_BUN_RUNFILES_DIR="
+)
+if defined RUNFILES_MANIFEST_VALUE (
+  set "RULES_BUN_RUNFILES_MANIFEST=%RUNFILES_MANIFEST_VALUE%"
+) else (
+  set "RULES_BUN_RUNFILES_MANIFEST="
+)
+
+"%BUN_BIN%" --bun "%RUNNER%" "%SPEC%" %*
+exit /b %ERRORLEVEL%
+
+:rlocation
+set "LOOKUP=%~1"
+set "OUTPUT_VAR=%~2"
+if defined RUNFILES_DIR_VALUE (
+  set "%OUTPUT_VAR%=%RUNFILES_DIR_VALUE%\\%LOOKUP:/=\\%"
+  exit /b 0
+)
+for /f "tokens=1,* delims= " %%A in ('findstr /b /c:"%LOOKUP% " "%RUNFILES_MANIFEST_VALUE%"') do (
+  set "%OUTPUT_VAR%=%%B"
+  exit /b 0
+)
+echo rules_bun: missing runfile %LOOKUP% 1>&2
+exit /b 1
+"""
+
+def runfiles_path(file):
+    workspace_name = file.owner.workspace_name
+    if workspace_name:
+        return "{}/{}".format(workspace_name, file.short_path)
+    return "_main/{}".format(file.short_path)
+
+def runtime_launcher_attrs():
+    return {
+        "_runtime_launcher": attr.label(
+            default = _RUNTIME_LAUNCHER,
+            allow_single_file = True,
+        ),
+        "_windows_constraint": attr.label(
+            default = _WINDOWS_CONSTRAINT,
+        ),
+    }
+
+def is_windows_target(ctx):
+    return ctx.target_platform_has_constraint(ctx.attr._windows_constraint[platform_common.ConstraintValueInfo])
+
+def write_launcher_spec(ctx, spec):
+    spec_file = ctx.actions.declare_file(ctx.label.name + ".launcher.json")
+    ctx.actions.write(
+        output = spec_file,
+        content = json.encode(spec) + "\n",
+    )
+    return spec_file
+
+def declare_runtime_wrapper(ctx, bun_bin, spec_file):
+    runner = ctx.file._runtime_launcher
+    wrapper = ctx.actions.declare_file(ctx.label.name + (".cmd" if is_windows_target(ctx) else ""))
+    content = _CMD_WRAPPER_TEMPLATE if is_windows_target(ctx) else _POSIX_WRAPPER_TEMPLATE
+    content = content.replace("__BUN_RUNFILES_PATH__", runfiles_path(bun_bin)).replace(
+        "__RUNNER_RUNFILES_PATH__",
+        runfiles_path(runner),
+    ).replace(
+        "__SPEC_RUNFILES_PATH__",
+        runfiles_path(spec_file),
+    )
+    ctx.actions.write(
+        output = wrapper,
+        content = content,
+        is_executable = True,
+    )
+    return struct(
+        executable = wrapper,
+        runner = runner,
+    )
--- a/internal/runtime_launcher.js
+++ b/internal/runtime_launcher.js
--- a/internal/workspace.bzl
+++ b/internal/workspace.bzl
@@ -1,11 +1,13 @@
-"""Shared Bun workspace metadata and launcher helpers."""
+"""Shared Bun workspace metadata helpers."""

 BunWorkspaceInfo = provider(
    doc = "Workspace/runtime metadata shared by Bun rules and adapters.",
    fields = {
        "install_metadata_file": "Optional install metadata file from bun_install.",
+        "install_repo_runfiles_path": "Runfiles root for the node_modules repository when present.",
        "metadata_file": "Rule-local metadata file describing the staged workspace inputs.",
        "node_modules_files": "Depset of node_modules files from bun_install.",
+        "node_modules_roots": "Sorted repo-relative node_modules roots available in runfiles.",
        "package_dir_hint": "Package-relative directory when known at analysis time.",
        "package_json": "Package manifest file when explicitly provided.",
        "primary_file": "Primary source file used to resolve the runtime package context.",
@@ -13,690 +15,41 @@ BunWorkspaceInfo = provider(
    },
 )

-_WORKSPACE_SETUP_TEMPLATE = """#!/usr/bin/env bash
-set -euo pipefail
-
-runfiles_dir="${RUNFILES_DIR:-$0.runfiles}"
-workspace_root="${runfiles_dir}/_main"
-workspace_root="$(cd "${workspace_root}" && pwd -P)"
-bun_bin="${runfiles_dir}/_main/__BUN_SHORT_PATH__"
-primary_source=""
-if [[ -n "__PRIMARY_SOURCE_SHORT_PATH__" ]]; then
-    primary_source="${runfiles_dir}/_main/__PRIMARY_SOURCE_SHORT_PATH__"
-fi
-package_json=""
-if [[ -n "__PACKAGE_JSON_SHORT_PATH__" ]]; then
-    package_json="${runfiles_dir}/_main/__PACKAGE_JSON_SHORT_PATH__"
-fi
-package_rel_dir_hint="__PACKAGE_DIR_HINT__"
-install_root_rel_dir_hint="__INSTALL_ROOT_REL_DIR__"
-install_metadata=""
-if [[ -n "__INSTALL_METADATA_SHORT_PATH__" ]]; then
-    install_metadata="${runfiles_dir}/_main/__INSTALL_METADATA_SHORT_PATH__"
-fi
-working_dir_mode="__WORKING_DIR_MODE__"
-
-normalize_rel_dir() {
-    local value="$1"
-    if [[ -z "${value}" || "${value}" == "." ]]; then
-        echo "."
-    else
-        echo "${value#./}"
-    fi
-}
-
-dirname_rel_dir() {
-    local value
-    value="$(normalize_rel_dir "$1")"
-    if [[ "${value}" == "." || "${value}" != */* ]]; then
-        echo "."
-        return 0
-    fi
-    echo "${value%/*}"
-}
-
-first_path_component() {
-    local value
-    value="$(normalize_rel_dir "$1")"
-    if [[ "${value}" == "." ]]; then
-        echo ""
-        return 0
-    fi
-    echo "${value%%/*}"
-}
-
-rel_dir_from_abs_path() {
-    local absolute_path="$1"
-    if [[ "${absolute_path}" == "${workspace_root}" ]]; then
-        echo "."
-        return 0
-    fi
-    echo "${absolute_path#"${workspace_root}/"}"
-}
-
-find_package_rel_dir_for_path() {
-    local path="$1"
-    local dir="$1"
-    if [[ -f "${dir}" ]]; then
-        dir="$(dirname "${dir}")"
-    fi
-
-    while [[ "${dir}" == "${workspace_root}"* ]]; do
-        if [[ -f "${dir}/package.json" ]]; then
-            rel_dir_from_abs_path "${dir}"
-            return 0
-        fi
-        if [[ "${dir}" == "${workspace_root}" ]]; then
-            break
-        fi
-        dir="$(dirname "${dir}")"
-    done
-
-    rel_dir_from_abs_path "$(dirname "${path}")"
-}
-
-find_working_rel_dir_for_path() {
-    local path="$1"
-    local dir="$1"
-    if [[ -f "${dir}" ]]; then
-        dir="$(dirname "${dir}")"
-    fi
-
-    while [[ "${dir}" == "${workspace_root}"* ]]; do
-        if [[ -f "${dir}/.env" || -f "${dir}/package.json" ]]; then
-            rel_dir_from_abs_path "${dir}"
-            return 0
-        fi
-        if [[ "${dir}" == "${workspace_root}" ]]; then
-            break
-        fi
-        dir="$(dirname "${dir}")"
-    done
-
-    rel_dir_from_abs_path "$(dirname "${path}")"
-}
-
-strip_rel_prefix() {
-    local child
-    child="$(normalize_rel_dir "$1")"
-    local parent
-    parent="$(normalize_rel_dir "$2")"
-
-    if [[ "${parent}" == "." ]]; then
-        echo "${child}"
-        return 0
-    fi
-    if [[ "${child}" == "${parent}" ]]; then
-        echo "."
-        return 0
-    fi
-    if [[ "${child}" == "${parent}/"* ]]; then
-        echo "${child#"${parent}/"}"
-        return 0
-    fi
-    echo "${child}"
-}
-
-select_primary_node_modules() {
-    local selected=""
-    local fallback=""
-    while IFS= read -r node_modules_dir; do
-        if [[ -z "${fallback}" ]]; then
-            fallback="${node_modules_dir}"
-        fi
-
-        if [[ ! -d "${node_modules_dir}/.bun" ]]; then
-            continue
-        fi
-
-        if [[ "${node_modules_dir}" != *"/runfiles/_main/"* ]]; then
-            selected="${node_modules_dir}"
-            break
-        fi
-
-        if [[ -z "${selected}" ]]; then
-            selected="${node_modules_dir}"
-        fi
-    done < <(find -L "${runfiles_dir}" -type d -name node_modules 2>/dev/null | sort)
-
-    if [[ -n "${selected}" ]]; then
-        echo "${selected}"
-    else
-        echo "${fallback}"
-    fi
-}
-
-link_top_level_entries() {
-    local source_root="$1"
-    local destination_root="$2"
-    local skipped_entry="$3"
-    local entry=""
-    local entry_name=""
-
-    shopt -s dotglob nullglob
-    for entry in "${source_root}"/* "${source_root}"/.[!.]* "${source_root}"/..?*; do
-        entry_name="$(basename "${entry}")"
-        if [[ "${entry_name}" == "." || "${entry_name}" == ".." ]]; then
-            continue
-        fi
-        if [[ -n "${skipped_entry}" && "${entry_name}" == "${skipped_entry}" ]]; then
-            continue
-        fi
-        ln -s "${entry}" "${destination_root}/${entry_name}"
-    done
-    shopt -u dotglob nullglob
-}
-
-materialize_package_path() {
-    local source_root="$1"
-    local destination_root="$2"
-    local package_rel_dir
-    package_rel_dir="$(normalize_rel_dir "$3")"
-
-    if [[ "${package_rel_dir}" == "." ]]; then
-        return 0
-    fi
-
-    local source_cursor="${source_root}"
-    local destination_cursor="${destination_root}"
-    local parts=()
-    local current="${package_rel_dir}"
-
-    while [[ -n "${current}" ]]; do
-        if [[ "${current}" == */* ]]; then
-            parts+=("${current%%/*}")
-            current="${current#*/}"
-        else
-            parts+=("${current}")
-            break
-        fi
-    done
-
-    local index=0
-    while [[ ${index} -lt $((${#parts[@]} - 1)) ]]; do
-        local part="${parts[${index}]}"
-        local next_part="${parts[$((index + 1))]}"
-        source_cursor="${source_cursor}/${part}"
-        destination_cursor="${destination_cursor}/${part}"
-        mkdir -p "${destination_cursor}"
-
-        local sibling=""
-        local sibling_name=""
-        shopt -s dotglob nullglob
-        for sibling in "${source_cursor}"/* "${source_cursor}"/.[!.]* "${source_cursor}"/..?*; do
-            sibling_name="$(basename "${sibling}")"
-            if [[ "${sibling_name}" == "." || "${sibling_name}" == ".." || "${sibling_name}" == "${next_part}" ]]; then
-                continue
-            fi
-            if [[ ! -e "${destination_cursor}/${sibling_name}" ]]; then
-                ln -s "${sibling}" "${destination_cursor}/${sibling_name}"
-            fi
-        done
-        shopt -u dotglob nullglob
-        index=$((index + 1))
-    done
-
-    mkdir -p "${destination_root}/${package_rel_dir}"
-}
-
-materialize_directory_entries() {
-    local source_root="$1"
-    local destination_root="$2"
-    local entry=""
-    local entry_name=""
-
-    mkdir -p "${destination_root}"
-    shopt -s dotglob nullglob
-    for entry in "${source_root}"/* "${source_root}"/.[!.]* "${source_root}"/..?*; do
-        entry_name="$(basename "${entry}")"
-        if [[ "${entry_name}" == "." || "${entry_name}" == ".." ]]; then
-            continue
-        fi
-        rm -rf "${destination_root}/${entry_name}"
-        ln -s "${entry}" "${destination_root}/${entry_name}"
-    done
-    shopt -u dotglob nullglob
-}
-
-stage_workspace_view() {
-    local source_root="$1"
-    local destination_root="$2"
-    local package_rel_dir
-    package_rel_dir="$(normalize_rel_dir "$3")"
-    local skipped_entry
-    skipped_entry="$(first_path_component "${package_rel_dir}")"
-
-    link_top_level_entries "${source_root}" "${destination_root}" "${skipped_entry}"
-
-    if [[ "${package_rel_dir}" == "." ]]; then
-        return 0
-    fi
-
-    materialize_package_path "${source_root}" "${destination_root}" "${package_rel_dir}"
-    materialize_directory_entries "${source_root}/${package_rel_dir}" "${destination_root}/${package_rel_dir}"
-}
-
-materialize_tree_contents() {
-    local source_root="$1"
-    local destination_root="$2"
-
-    rm -rf "${destination_root}"
-    mkdir -p "${destination_root}"
-    cp -RL "${source_root}/." "${destination_root}"
-}
-
-build_workspace_package_map() {
-    local root="$1"
-    local out="$2"
-
-    python3 - "${root}" >"${out}" <<'PY'
-import json
-import os
-import sys
-
-root = os.path.abspath(sys.argv[1])
-
-for dirpath, dirnames, filenames in os.walk(root):
-    dirnames[:] = [name for name in dirnames if name != "node_modules"]
-    if "package.json" not in filenames:
-        continue
-
-    manifest_path = os.path.join(dirpath, "package.json")
-    try:
-        with open(manifest_path, "r", encoding="utf-8") as manifest_file:
-            package_name = json.load(manifest_file).get("name")
-    except Exception:
-        continue
-
-    if not isinstance(package_name, str):
-        continue
-
-    rel_dir = os.path.relpath(dirpath, root)
-    if rel_dir == ".":
-        rel_dir = "."
-    print(f"{package_name}\t{rel_dir}")
-PY
-}
-
-workspace_package_rel_dir_for_source() {
-    local source="$1"
-    local manifest_path="${source}/package.json"
-    local package_name=""
-
-    if [[ ! -f "${manifest_path}" ]]; then
-        return 1
-    fi
-
-    package_name="$(python3 - "${manifest_path}" <<'PY'
-import json
-import sys
-
-try:
-    with open(sys.argv[1], "r", encoding="utf-8") as manifest_file:
-        package_name = json.load(manifest_file).get("name", "")
-except Exception:
-    package_name = ""
-
-if isinstance(package_name, str):
-    print(package_name)
-PY
-)"
-
-    if [[ -z "${package_name}" ]]; then
-        return 1
-    fi
-
-    awk -F '\t' -v name="${package_name}" '$1 == name { print $2; exit }' "${workspace_package_map}"
-}
-
-link_node_modules_entry() {
-    local source="$1"
-    local destination="$2"
-    local workspace_rel_dir=""
-
-    rm -rf "${destination}"
-    workspace_rel_dir="$(workspace_package_rel_dir_for_source "${source}" || true)"
-    if [[ -n "${workspace_rel_dir}" ]]; then
-        ln -s "${runtime_workspace}/${workspace_rel_dir}" "${destination}"
-        return 0
-    fi
-
-    if [[ -L "${source}" ]]; then
-        ln -s "$(readlink "${source}")" "${destination}"
-    else
-        ln -s "${source}" "${destination}"
-    fi
-}
-
-mirror_node_modules_dir() {
-    local source_dir="$1"
-    local destination_dir="$2"
-    local entry=""
-    local entry_name=""
-    local scoped_entry=""
-    local scoped_name=""
-
-    rm -rf "${destination_dir}"
-    mkdir -p "${destination_dir}"
-
-    shopt -s dotglob nullglob
-    for entry in "${source_dir}"/* "${source_dir}"/.[!.]* "${source_dir}"/..?*; do
-        entry_name="$(basename "${entry}")"
-        if [[ "${entry_name}" == "." || "${entry_name}" == ".." || "${entry_name}" == ".rules_bun" ]]; then
-            continue
-        fi
-
-        if [[ -d "${entry}" && ! -L "${entry}" && "${entry_name}" == @* ]]; then
-            mkdir -p "${destination_dir}/${entry_name}"
-            for scoped_entry in "${entry}"/* "${entry}"/.[!.]* "${entry}"/..?*; do
-                scoped_name="$(basename "${scoped_entry}")"
-                if [[ "${scoped_name}" == "." || "${scoped_name}" == ".." ]]; then
-                    continue
-                fi
-                link_node_modules_entry "${scoped_entry}" "${destination_dir}/${entry_name}/${scoped_name}"
-            done
-            continue
-        fi
-
-        link_node_modules_entry "${entry}" "${destination_dir}/${entry_name}"
-    done
-    shopt -u dotglob nullglob
-}
-
-find_install_repo_node_modules() {
-    local repo_root="$1"
-    local package_rel_dir
-    package_rel_dir="$(normalize_rel_dir "$2")"
-
-    if [[ "${package_rel_dir}" != "." ]]; then
-        local candidate="${package_rel_dir}"
-        while true; do
-            if [[ -d "${repo_root}/${candidate}/node_modules" ]]; then
-                echo "${repo_root}/${candidate}/node_modules"
-                return 0
-            fi
-
-            if [[ "${candidate}" != */* ]]; then
-                break
-            fi
-            candidate="${candidate%/*}"
-        done
-    fi
-
-    if [[ -d "${repo_root}/node_modules" ]]; then
-        echo "${repo_root}/node_modules"
-        return 0
-    fi
-
-    return 1
-}
-
-mirror_install_repo_workspace_node_modules() {
-    local repo_root="$1"
-    local destination_root="$2"
-
-    while IFS= read -r install_node_modules; do
-        local rel_path="${install_node_modules#${repo_root}/}"
-        local destination="${destination_root}/${rel_path}"
-
-        mkdir -p "$(dirname "${destination}")"
-        mirror_node_modules_dir "${install_node_modules}" "${destination}"
-    done < <(find "${repo_root}" \
-        -path "${repo_root}/node_modules" -prune -o \
-        -type d -name node_modules -print 2>/dev/null | sort)
-}
-
-build_runtime_path() {
-    local workspace_dir="$1"
-    local package_dir="$2"
-    local install_root_dir="$3"
-    local entries=()
-
-    if [[ -d "${install_root_dir}/node_modules/.bin" ]]; then
-        entries+=("${install_root_dir}/node_modules/.bin")
-    fi
-    if [[ -d "${package_dir}/node_modules/.bin" ]]; then
-        if [[ "${package_dir}/node_modules/.bin" != "${install_root_dir}/node_modules/.bin" ]]; then
-            entries+=("${package_dir}/node_modules/.bin")
-        fi
-    fi
-    if [[ -d "${workspace_dir}/node_modules/.bin" && "${workspace_dir}/node_modules/.bin" != "${package_dir}/node_modules/.bin" && "${workspace_dir}/node_modules/.bin" != "${install_root_dir}/node_modules/.bin" ]]; then
-        entries+=("${workspace_dir}/node_modules/.bin")
-    fi
-    if [[ -n "${PATH:-}" ]]; then
-        entries+=("${PATH}")
-    fi
-
-    if [[ ${#entries[@]} -eq 0 ]]; then
-        echo ""
-        return 0
-    fi
-
-    local path_value=""
-    local entry=""
-    for entry in "${entries[@]}"; do
-        if [[ -z "${path_value}" ]]; then
-            path_value="${entry}"
-        else
-            path_value="${path_value}:${entry}"
-        fi
-    done
-    echo "${path_value}"
-}
-
-resolve_package_rel_dir() {
-    if [[ -n "${package_rel_dir_hint}" && "${package_rel_dir_hint}" != "." ]]; then
-        normalize_rel_dir "${package_rel_dir_hint}"
-        return 0
-    fi
-    if [[ -n "${package_json}" ]]; then
-        find_package_rel_dir_for_path "${package_json}"
-        return 0
-    fi
-    if [[ -n "${primary_source}" ]]; then
-        find_package_rel_dir_for_path "${primary_source}"
-        return 0
-    fi
-    echo "."
-}
-
-resolve_execution_rel_dir() {
-    local package_rel_dir="$1"
-    case "${working_dir_mode}" in
-        workspace)
-            echo "."
-            ;;
-        package)
-            echo "${package_rel_dir}"
-            ;;
-        entry_point)
-            if [[ -n "${primary_source}" ]]; then
-                find_working_rel_dir_for_path "${primary_source}"
-            else
-                echo "${package_rel_dir}"
-            fi
-            ;;
-        *)
-            echo "${package_rel_dir}"
-            ;;
-    esac
-}
-
-resolve_install_root_rel_dir() {
-    if [[ -n "${install_metadata}" && -f "${install_metadata}" ]]; then
-        local resolved_from_metadata=""
-        resolved_from_metadata="$(
-            python3 - "${install_metadata}" "${package_rel_dir}" <<'PY'
-import json
-import sys
-
-install_metadata_path = sys.argv[1]
-package_rel_dir = sys.argv[2]
-
-try:
-    with open(install_metadata_path, "r", encoding="utf-8") as install_metadata_file:
-        workspace_package_dirs = json.load(install_metadata_file).get("workspace_package_dirs", [])
-except Exception:
-    workspace_package_dirs = []
-
-normalized_package_rel_dir = package_rel_dir.strip("./") or "."
-matches = []
-for workspace_package_dir in workspace_package_dirs:
-    normalized_workspace_package_dir = workspace_package_dir.strip("./")
-    if not normalized_workspace_package_dir:
-        continue
-    if normalized_package_rel_dir == normalized_workspace_package_dir:
-        matches.append((len(normalized_workspace_package_dir), "."))
-        continue
-    suffix = "/" + normalized_workspace_package_dir
-    if normalized_package_rel_dir.endswith(suffix):
-        prefix = normalized_package_rel_dir[:-len(suffix)].strip("/") or "."
-        matches.append((len(normalized_workspace_package_dir), prefix))
-
-if matches:
-    matches.sort(reverse = True)
-    print(matches[0][1])
-PY
-        )"
-        if [[ -n "${resolved_from_metadata}" ]]; then
-            echo "${resolved_from_metadata}"
-            return 0
-        fi
-    fi
-    if [[ -n "${install_root_rel_dir_hint}" && "${install_root_rel_dir_hint}" != "." ]]; then
-        normalize_rel_dir "${install_root_rel_dir_hint}"
-        return 0
-    fi
-    if [[ -n "${package_json}" ]]; then
-        find_package_rel_dir_for_path "${package_json}"
-        return 0
-    fi
-    if [[ -n "${primary_source}" ]]; then
-        find_package_rel_dir_for_path "${primary_source}"
-        return 0
-    fi
-    echo "."
-}
-
-package_rel_dir="$(resolve_package_rel_dir)"
-execution_rel_dir="$(resolve_execution_rel_dir "${package_rel_dir}")"
-install_root_rel_dir="$(resolve_install_root_rel_dir)"
-package_rel_dir_in_install_root="$(strip_rel_prefix "${package_rel_dir}" "${install_root_rel_dir}")"
-
-runtime_workspace="$(mktemp -d)"
-cleanup_runtime_workspace() {
-    rm -rf "${runtime_workspace}"
-}
-
-stage_workspace_view "${workspace_root}" "${runtime_workspace}" "${package_rel_dir}"
-runtime_package_dir="${runtime_workspace}"
-if [[ "${package_rel_dir}" != "." ]]; then
-    runtime_package_dir="${runtime_workspace}/${package_rel_dir}"
-fi
-runtime_install_root="${runtime_workspace}"
-if [[ "${install_root_rel_dir}" != "." ]]; then
-    runtime_install_root="${runtime_workspace}/${install_root_rel_dir}"
-fi
-runtime_exec_dir="${runtime_workspace}"
-if [[ "${execution_rel_dir}" != "." ]]; then
-    runtime_exec_dir="${runtime_workspace}/${execution_rel_dir}"
-fi
-
-if [[ -n "${primary_source}" ]]; then
-    materialize_tree_contents "${workspace_root}/${package_rel_dir}" "${runtime_package_dir}"
-fi
-
-if [[ -n "${package_json}" ]]; then
-    materialize_tree_contents "${workspace_root}/${install_root_rel_dir}" "${runtime_install_root}"
-fi
-
-if [[ -n "${primary_source}" && "${primary_source}" == "${workspace_root}"* ]]; then
-    primary_source="${runtime_workspace}/$(rel_dir_from_abs_path "${primary_source}")"
-fi
-
-if [[ -n "${package_json}" && "${package_json}" == "${workspace_root}"* ]]; then
-    package_json="${runtime_workspace}/$(rel_dir_from_abs_path "${package_json}")"
-fi
-
-workspace_package_map="${runtime_workspace}/.rules_bun_workspace_packages.tsv"
-build_workspace_package_map "${runtime_workspace}" "${workspace_package_map}"
-
-primary_node_modules="$(select_primary_node_modules)"
-install_repo_root=""
-if [[ -n "${primary_node_modules}" ]]; then
-    install_repo_root="$(dirname "${primary_node_modules}")"
-    mkdir -p "${runtime_install_root}"
-    mirror_node_modules_dir "${primary_node_modules}" "${runtime_install_root}/node_modules"
-fi
-
-if [[ -n "${install_repo_root}" ]]; then
-    resolved_install_node_modules="$(find_install_repo_node_modules "${install_repo_root}" "${package_rel_dir_in_install_root}" || true)"
-    if [[ -n "${resolved_install_node_modules}" && "${resolved_install_node_modules}" != "${install_repo_root}/node_modules" ]]; then
-        mirror_node_modules_dir "${resolved_install_node_modules}" "${runtime_package_dir}/node_modules"
-    fi
-    mirror_install_repo_workspace_node_modules "${install_repo_root}" "${runtime_install_root}"
-fi
-
-if [[ ! -e "${runtime_package_dir}/node_modules" && -e "${runtime_install_root}/node_modules" && "${runtime_package_dir}" != "${runtime_install_root}" ]]; then
-    ln -s "${runtime_install_root}/node_modules" "${runtime_package_dir}/node_modules"
-fi
-
-runtime_path="$(build_runtime_path "${runtime_workspace}" "${runtime_package_dir}" "${runtime_install_root}")"
-if [[ -n "${runtime_path}" ]]; then
-    export PATH="${runtime_path}"
-fi
-"""
-
-def _shell_quote(value):
-    return "'" + value.replace("'", "'\"'\"'") + "'"
-
-def _dirname(path):
-    if not path or path == ".":
-        return "."
-
-    index = path.rfind("/")
-    if index < 0:
-        return "."
-    if index == 0:
-        return "/"
-    return path[:index]
-
 def find_install_metadata_file(files):
    for file in files:
        if file.short_path.endswith("node_modules/.rules_bun/install.json"):
            return file
    return None

-def resolve_node_modules_roots(files, workspace_dir = ""):
-    install_metadata_file = find_install_metadata_file(files)
-    shared_node_modules_root = None
-    workspace_node_modules_root = None
+def _runfiles_workspace(file):
+    workspace_name = file.owner.workspace_name
+    if workspace_name:
+        return workspace_name
+    return "_main"

-    if install_metadata_file:
-        shared_node_modules_root = _dirname(_dirname(install_metadata_file.path))
+def _repo_relative_short_path(file):
+    short_path = file.short_path.replace("\\", "/")
+    workspace_name = _runfiles_workspace(file)
+    external_prefix = "../{}/".format(workspace_name)
+    if short_path.startswith(external_prefix):
+        return short_path[len(external_prefix):]
+    if short_path == "../{}".format(workspace_name):
+        return "."
+    return short_path

-    workspace_marker = ""
-    if workspace_dir:
-        workspace_marker = "/%s/node_modules/" % workspace_dir.strip("/")
-
-    shortest_path = None
-    for src in files:
-        if workspace_marker and workspace_marker in src.path and workspace_node_modules_root == None:
-            workspace_node_modules_root = src.path[:src.path.find(workspace_marker) + len(workspace_marker) - 1]
-        if shortest_path == None or len(src.path) < len(shortest_path):
-            shortest_path = src.path
-
-    if shared_node_modules_root == None and shortest_path:
+def resolve_node_modules_roots(files):
+    roots = {}
    marker = "/node_modules/"
-        marker_index = shortest_path.find(marker)
-        if marker_index >= 0:
-            shared_node_modules_root = shortest_path[:marker_index + len("/node_modules")]
+    for file in files:
+        short_path = _repo_relative_short_path(file)
+        if short_path == "node_modules" or short_path.startswith("node_modules/"):
+            roots["node_modules"] = True

-    return struct(
-        install_metadata_file = install_metadata_file,
-        node_modules_root = workspace_node_modules_root or shared_node_modules_root,
-        shared_node_modules_root = shared_node_modules_root,
-    )
+        marker_index = short_path.find(marker)
+        if marker_index >= 0:
+            roots[short_path[:marker_index + len("/node_modules")]] = True
+
+    return sorted(roots.keys())

 def create_bun_workspace_info(ctx, primary_file = None, package_json = None, package_dir_hint = ".", extra_files = None):
    direct_runtime_files = []
@@ -708,15 +61,25 @@ def create_bun_workspace_info(ctx, primary_file = None, package_json = None, pac

    node_modules_files = depset()
    install_metadata_file = None
+    install_repo_runfiles_path = ""
+    node_modules_roots = []
    if getattr(ctx.attr, "node_modules", None):
        node_modules_files = ctx.attr.node_modules[DefaultInfo].files
-        install_metadata_file = find_install_metadata_file(node_modules_files.to_list())
+        node_modules_file_list = node_modules_files.to_list()
+        install_metadata_file = find_install_metadata_file(node_modules_file_list)
+        node_modules_roots = resolve_node_modules_roots(node_modules_file_list)
+        if install_metadata_file:
+            install_repo_runfiles_path = _runfiles_workspace(install_metadata_file)
+        elif node_modules_file_list:
+            install_repo_runfiles_path = _runfiles_workspace(node_modules_file_list[0])

    metadata_file = ctx.actions.declare_file(ctx.label.name + ".bun_workspace.json")
    ctx.actions.write(
        output = metadata_file,
        content = json.encode({
            "install_metadata": install_metadata_file.short_path if install_metadata_file else "",
+            "install_repo_runfiles_path": install_repo_runfiles_path,
+            "node_modules_roots": node_modules_roots,
            "package_dir_hint": package_dir_hint or ".",
            "package_json": package_json.short_path if package_json else "",
            "primary_file": primary_file.short_path if primary_file else "",
@@ -731,8 +94,10 @@ def create_bun_workspace_info(ctx, primary_file = None, package_json = None, pac

    return BunWorkspaceInfo(
        install_metadata_file = install_metadata_file,
+        install_repo_runfiles_path = install_repo_runfiles_path,
        metadata_file = metadata_file,
        node_modules_files = node_modules_files,
+        node_modules_roots = node_modules_roots,
        package_dir_hint = package_dir_hint or ".",
        package_json = package_json,
        primary_file = primary_file,
@@ -746,31 +111,3 @@ def workspace_runfiles(ctx, workspace_info, direct_files = None, transitive_file
            transitive = [workspace_info.runtime_files] + (transitive_files or []),
        ),
    )
-
-def render_workspace_setup(
-        bun_short_path,
-        working_dir_mode,
-        primary_source_short_path = "",
-        package_json_short_path = "",
-        package_dir_hint = ".",
-        install_root_rel_dir = ".",
-        install_metadata_short_path = ""):
-    return _WORKSPACE_SETUP_TEMPLATE.replace("__BUN_SHORT_PATH__", bun_short_path).replace(
-        "__PRIMARY_SOURCE_SHORT_PATH__",
-        primary_source_short_path,
-    ).replace(
-        "__PACKAGE_JSON_SHORT_PATH__",
-        package_json_short_path,
-    ).replace(
-        "__PACKAGE_DIR_HINT__",
-        package_dir_hint or ".",
-    ).replace(
-        "__INSTALL_ROOT_REL_DIR__",
-        install_root_rel_dir or ".",
-    ).replace(
-        "__INSTALL_METADATA_SHORT_PATH__",
-        install_metadata_short_path,
-    ).replace(
-        "__WORKING_DIR_MODE__",
-        working_dir_mode,
-    )
--- a/tests/binary_test/BUILD.bazel
+++ b/tests/binary_test/BUILD.bazel
@@ -1,5 +1,5 @@
-load("//bun:defs.bzl", "bun_binary")
 load("@rules_shell//shell:sh_test.bzl", "sh_test")
+load("//bun:defs.bzl", "bun_binary")

 bun_binary(
    name = "hello_js_bin",
@@ -8,8 +8,12 @@ bun_binary(

 sh_test(
    name = "bun_binary_js_test",
+    size = "small",
    srcs = ["run_binary.sh"],
-    args = ["$(location :hello_js_bin)", "hello-js"],
+    args = [
+        "$(location :hello_js_bin)",
+        "hello-js",
+    ],
    data = [":hello_js_bin"],
 )

@@ -20,19 +24,24 @@ bun_binary(

 sh_test(
    name = "bun_binary_ts_test",
+    size = "small",
    srcs = ["run_binary.sh"],
-    args = ["$(location :hello_ts_bin)", "hello-ts"],
+    args = [
+        "$(location :hello_ts_bin)",
+        "hello-ts",
+    ],
    data = [":hello_ts_bin"],
 )

 bun_binary(
    name = "hello_js_with_data_bin",
-    entry_point = "hello.js",
    data = ["payload.txt"],
+    entry_point = "hello.js",
 )

 sh_test(
    name = "bun_binary_data_test",
+    size = "small",
    srcs = ["verify_data_shape.sh"],
    args = [
        "$(location //internal:bun_binary.bzl)",
@@ -46,13 +55,14 @@ sh_test(

 bun_binary(
    name = "env_cwd_bin",
-    entry_point = "env.ts",
    data = [".env"],
+    entry_point = "env.ts",
    working_dir = "entry_point",
 )

 sh_test(
    name = "bun_binary_env_cwd_test",
+    size = "small",
    srcs = ["run_env_binary.sh"],
    args = ["$(location :env_cwd_bin)"],
    data = [":env_cwd_bin"],
@@ -60,13 +70,14 @@ sh_test(

 bun_binary(
    name = "env_parent_cwd_bin",
-    entry_point = "env_parent/src/main.ts",
    data = ["env_parent/.env"],
+    entry_point = "env_parent/src/main.ts",
    working_dir = "entry_point",
 )

 sh_test(
    name = "bun_binary_env_parent_cwd_test",
+    size = "small",
    srcs = ["run_parent_env_binary.sh"],
    args = ["$(location :env_parent_cwd_bin)"],
    data = [":env_parent_cwd_bin"],
@@ -74,14 +85,18 @@ sh_test(

 bun_binary(
    name = "runtime_flag_bin",
+    args = [
+        "one",
+        "two",
+    ],
    entry_point = "flag_probe.ts",
-    args = ["one", "two"],
-    preload = ["preload.ts"],
    env_files = ["runtime.env"],
+    preload = ["preload.ts"],
 )

 sh_test(
    name = "bun_binary_runtime_flags_test",
+    size = "small",
    srcs = ["run_flag_binary.sh"],
    args = ["$(location :runtime_flag_bin)"],
    data = [":runtime_flag_bin"],
@@ -89,6 +104,7 @@ sh_test(

 sh_test(
    name = "bun_binary_runtime_flags_shape_test",
+    size = "small",
    srcs = ["verify_runtime_flags_shape.sh"],
    args = ["$(location :runtime_flag_bin)"],
    data = [":runtime_flag_bin"],
@@ -96,24 +112,52 @@ sh_test(

 bun_binary(
    name = "configured_launcher_bin",
-    entry_point = "hello.ts",
-    node_modules = "@script_test_vite_node_modules//:node_modules",
-    smol = True,
    conditions = [
        "browser",
        "development",
    ],
+    entry_point = "hello.ts",
+    inherit_host_path = True,
    install_mode = "force",
+    node_modules = "@script_test_vite_node_modules//:node_modules",
    run_flags = [
        "--hot",
        "--console-depth",
        "4",
    ],
+    smol = True,
+    visibility = ["//tests/ci_test:__pkg__"],
 )

 sh_test(
    name = "bun_binary_configured_launcher_shape_test",
+    size = "small",
    srcs = ["verify_configured_launcher_shape.sh"],
    args = ["$(location :configured_launcher_bin)"],
    data = [":configured_launcher_bin"],
 )
+
+bun_binary(
+    name = "path_default_bin",
+    entry_point = "path_probe.ts",
+)
+
+bun_binary(
+    name = "path_inherit_bin",
+    entry_point = "path_probe.ts",
+    inherit_host_path = True,
+)
+
+sh_test(
+    name = "bun_binary_host_path_test",
+    size = "small",
+    srcs = ["run_path_binary.sh"],
+    args = [
+        "$(location :path_default_bin)",
+        "$(location :path_inherit_bin)",
+    ],
+    data = [
+        ":path_default_bin",
+        ":path_inherit_bin",
+    ],
+)
--- a/tests/binary_test/path_probe.ts
+++ b/tests/binary_test/path_probe.ts
@@ -0,0 +1,5 @@
+const pathValue = process.env.PATH ?? "";
+
+console.log(JSON.stringify({
+  hasHostSentinel: pathValue.includes("rules_bun_host_path_sentinel"),
+}));
--- a/tests/binary_test/run_binary.sh
+++ b/tests/binary_test/run_binary.sh
@@ -3,7 +3,23 @@ set -euo pipefail

 binary="$1"
 expected="$2"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "${expected}" ]]; then
  echo "Unexpected output from ${binary}: ${output}" >&2
--- a/tests/binary_test/run_env_binary.sh
+++ b/tests/binary_test/run_env_binary.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "from-dotenv" ]]; then
  echo "Expected .env value from entry-point directory, got: ${output}" >&2
--- a/tests/binary_test/run_flag_binary.sh
+++ b/tests/binary_test/run_flag_binary.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 expected='{"preloaded":"yes","env":"from-env-file","argv":["one","two"]}'

--- a/tests/binary_test/run_parent_env_binary.sh
+++ b/tests/binary_test/run_parent_env_binary.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "from-parent-dotenv" ]]; then
  echo "Expected .env value from parent directory, got: ${output}" >&2
--- a/tests/binary_test/run_path_binary.sh
+++ b/tests/binary_test/run_path_binary.sh
@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+default_binary="$1"
+inherit_binary="$2"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    env PATH="rules_bun_host_path_sentinel:${PATH:-}" cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  env PATH="rules_bun_host_path_sentinel:${PATH:-}" "${launcher}" "$@"
+}
+
+default_output="$(run_launcher "${default_binary}")"
+inherit_output="$(run_launcher "${inherit_binary}")"
+
+if [[ ${default_output} != '{"hasHostSentinel":false}' ]]; then
+  echo "Expected default launcher to hide host PATH, got: ${default_output}" >&2
+  exit 1
+fi
+
+if [[ ${inherit_output} != '{"hasHostSentinel":true}' ]]; then
+  echo "Expected inherit_host_path launcher to preserve host PATH, got: ${inherit_output}" >&2
+  exit 1
+fi
--- a/tests/binary_test/verify_configured_launcher_shape.sh
+++ b/tests/binary_test/verify_configured_launcher_shape.sh
@@ -1,16 +1,23 @@
 #!/usr/bin/env bash
 set -euo pipefail

-binary="$1"
+launcher="$1"

-grep -Fq -- 'install_metadata="${runfiles_dir}/_main/' "${binary}"
-grep -Fq -- 'node_modules/.rules_bun/install.json' "${binary}"
-grep -Fq -- "--smol" "${binary}"
-grep -Fq -- "--conditions" "${binary}"
-grep -Fq -- "'browser'" "${binary}"
-grep -Fq -- "'development'" "${binary}"
-grep -Fq -- "--install" "${binary}"
-grep -Fq -- "'force'" "${binary}"
-grep -Fq -- "'--hot'" "${binary}"
-grep -Fq -- "'--console-depth'" "${binary}"
-grep -Fq -- "'4'" "${binary}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+argv = spec["argv"]
+
+assert spec["install_metadata_short_path"].endswith("node_modules/.rules_bun/install.json"), spec
+assert spec["inherit_host_path"] is True, spec
+assert spec["node_modules_roots"], spec
+assert all(not root.startswith("../") for root in spec["node_modules_roots"]), spec
+for value in ["--smol", "--conditions", "browser", "development", "--install", "force", "--hot", "--console-depth", "4"]:
+    assert value in argv, (value, spec)
+PY
--- a/tests/binary_test/verify_runtime_flags_shape.sh
+++ b/tests/binary_test/verify_runtime_flags_shape.sh
@@ -1,8 +1,20 @@
 #!/usr/bin/env bash
 set -euo pipefail

-binary="$1"
+launcher="$1"

-grep -Fq -- '--no-install' "${binary}"
-grep -Fq -- '--preload' "${binary}"
-grep -Fq -- '--env-file' "${binary}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+assert "--no-install" in spec["argv"], spec
+assert spec["inherit_host_path"] is False, spec
+assert spec["preload_short_paths"] and spec["preload_short_paths"][0].endswith("tests/binary_test/preload.ts"), spec
+assert spec["env_file_short_paths"] and spec["env_file_short_paths"][0].endswith("tests/binary_test/runtime.env"), spec
+PY
--- a/tests/bun_test_test/BUILD.bazel
+++ b/tests/bun_test_test/BUILD.bazel
@@ -3,42 +3,62 @@ load("//bun:defs.bzl", "bun_test")

 bun_test(
    name = "passing_suite",
+    size = "small",
    srcs = ["passing.test.ts"],
 )

 bun_test(
    name = "failing_suite",
+    size = "small",
    srcs = ["failing.test.ts"],
 )

 bun_test(
    name = "configured_suite",
+    size = "small",
    srcs = ["passing.test.ts"],
-    preload = ["preload.ts"],
-    env_files = ["test.env"],
-    no_env_file = True,
-    timeout_ms = 250,
-    update_snapshots = True,
-    rerun_each = 2,
-    concurrent = True,
-    randomize = True,
-    seed = 7,
    bail = 1,
-    reporter = "junit",
-    max_concurrency = 4,
+    concurrent = True,
    coverage = True,
    coverage_reporters = ["lcov"],
+    env_files = ["test.env"],
+    max_concurrency = 4,
+    no_env_file = True,
+    preload = ["preload.ts"],
+    randomize = True,
+    reporter = "junit",
+    rerun_each = 2,
+    seed = 7,
    test_flags = ["--only-failures"],
+    timeout_ms = 250,
+    update_snapshots = True,
+    visibility = ["//tests/ci_test:__pkg__"],
 )

 bun_test(
    name = "configured_retry_suite",
+    size = "small",
    srcs = ["passing.test.ts"],
    retry = 3,
 )

+sh_test(
+    name = "bun_test_configured_suite_shape_test",
+    size = "small",
+    srcs = ["configured_suite_shape.sh"],
+    args = [
+        "$(location :configured_suite)",
+        "$(location :configured_retry_suite)",
+    ],
+    data = [
+        ":configured_retry_suite",
+        ":configured_suite",
+    ],
+)
+
 sh_test(
    name = "bun_test_failing_suite_test",
+    size = "small",
    srcs = ["failing_suite_shape.sh"],
    args = ["$(location //tests/bun_test_test:BUILD.bazel)"],
    data = ["//tests/bun_test_test:BUILD.bazel"],
@@ -46,34 +66,24 @@ sh_test(

 sh_test(
    name = "bun_test_cache_hit_test",
+    size = "small",
    srcs = ["cache_hit_shape.sh"],
-    args = ["$(location //internal:bun_test.bzl)"],
-    data = ["//internal:bun_test.bzl"],
+    args = ["$(location :passing_suite)"],
+    data = [":passing_suite"],
 )

 sh_test(
    name = "bun_test_cache_miss_test",
+    size = "small",
    srcs = ["cache_miss_shape.sh"],
-    args = ["$(location //internal:bun_test.bzl)"],
-    data = ["//internal:bun_test.bzl"],
+    args = ["$(location :configured_suite)"],
+    data = [":configured_suite"],
 )

 sh_test(
    name = "bun_test_junit_output_test",
+    size = "small",
    srcs = ["junit_shape.sh"],
-    args = ["$(location //internal:bun_test.bzl)"],
-    data = ["//internal:bun_test.bzl"],
-)
-
-sh_test(
-    name = "bun_test_configured_suite_shape_test",
-    srcs = ["configured_suite_shape.sh"],
-    args = [
-        "$(location :configured_suite)",
-        "$(location :configured_retry_suite)",
-    ],
-    data = [
-        ":configured_suite",
-        ":configured_retry_suite",
-    ],
+    args = ["$(location :configured_suite)"],
+    data = [":configured_suite"],
 )
--- a/tests/bun_test_test/cache_hit_shape.sh
+++ b/tests/bun_test_test/cache_hit_shape.sh
@@ -1,7 +1,19 @@
 #!/usr/bin/env bash
 set -euo pipefail

-rule_file="$1"
+launcher="$1"

-grep -Fq 'launcher_lines = [render_shell_array("bun_args", ["--bun", "test"])]' "${rule_file}"
-grep -Fq 'exec "${bun_bin}" "${bun_args[@]}" "$@"' "${rule_file}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+assert spec["kind"] == "bun_test", spec
+assert spec["argv"][:2] == ["--bun", "test"], spec
+assert spec["test_short_paths"], spec
+PY
--- a/tests/bun_test_test/cache_miss_shape.sh
+++ b/tests/bun_test_test/cache_miss_shape.sh
@@ -1,8 +1,20 @@
 #!/usr/bin/env bash
 set -euo pipefail

-rule_file="$1"
+launcher="$1"

-grep -Fq 'extra_files = ctx.files.srcs + ctx.files.data + ctx.files.preload + ctx.files.env_files + [bun_bin]' "${rule_file}"
-grep -Eq '"srcs": attr\.label_list\(' "${rule_file}"
-grep -Eq '"coverage": attr\.bool\(' "${rule_file}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+assert spec["coverage"] is True, spec
+assert spec["preload_short_paths"], spec
+assert spec["env_file_short_paths"], spec
+assert spec["test_short_paths"], spec
+PY
--- a/tests/bun_test_test/configured_suite_shape.sh
+++ b/tests/bun_test_test/configured_suite_shape.sh
@@ -4,21 +4,39 @@ set -euo pipefail
 launcher="$1"
 retry_launcher="$2"

-grep -Fq -- '--no-install' "${launcher}"
-grep -Fq -- '--preload' "${launcher}"
-grep -Fq -- '--env-file' "${launcher}"
-grep -Fq -- '--no-env-file' "${launcher}"
-grep -Fq -- '--timeout' "${launcher}"
-grep -Fq -- '--update-snapshots' "${launcher}"
-grep -Fq -- '--rerun-each' "${launcher}"
-grep -Fq -- '--concurrent' "${launcher}"
-grep -Fq -- '--randomize' "${launcher}"
-grep -Fq -- '--seed' "${launcher}"
-grep -Fq -- '--bail' "${launcher}"
-grep -Fq -- '--max-concurrency' "${launcher}"
-grep -Fq -- '--reporter' "${launcher}"
-grep -Fq -- '--reporter-outfile' "${launcher}"
-grep -Fq -- '--coverage' "${launcher}"
-grep -Fq -- '--coverage-dir' "${launcher}"
-grep -Fq -- '--coverage-reporter' "${launcher}"
-grep -Fq -- '--retry' "${retry_launcher}"
+python3 - "${launcher}" "${retry_launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+def read_spec(launcher: str):
+    path = pathlib.Path(launcher)
+    if path.suffix.lower() == ".cmd":
+        path = pathlib.Path(str(path)[:-4])
+    return json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+launcher_spec = read_spec(sys.argv[1])
+retry_spec = read_spec(sys.argv[2])
+
+for value in [
+    "--no-install",
+    "--no-env-file",
+    "--timeout",
+    "--update-snapshots",
+    "--rerun-each",
+    "--concurrent",
+    "--randomize",
+    "--seed",
+    "--bail",
+    "--max-concurrency",
+]:
+    assert value in launcher_spec["argv"], (value, launcher_spec)
+
+assert launcher_spec["preload_short_paths"], launcher_spec
+assert launcher_spec["env_file_short_paths"], launcher_spec
+assert launcher_spec["reporter"] == "junit", launcher_spec
+assert launcher_spec["coverage"] is True, launcher_spec
+assert launcher_spec["coverage_reporters"] == ["lcov"], launcher_spec
+assert "--retry" in retry_spec["argv"], retry_spec
+assert "3" in retry_spec["argv"], retry_spec
+PY
--- a/tests/bun_test_test/junit_shape.sh
+++ b/tests/bun_test_test/junit_shape.sh
@@ -1,7 +1,17 @@
 #!/usr/bin/env bash
 set -euo pipefail

-rule_file="$1"
+launcher="$1"

-grep -Fq 'reporter_out="${XML_OUTPUT_FILE:-${runtime_workspace}/junit.xml}"' "${rule_file}"
-grep -Fq 'bun_args+=("--reporter" "junit" "--reporter-outfile" "${reporter_out}")' "${rule_file}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+assert spec["reporter"] == "junit", spec
+PY
--- a/tests/bundle_test/BUILD.bazel
+++ b/tests/bundle_test/BUILD.bazel
@@ -1,5 +1,5 @@
-load("//bun:defs.bzl", "bun_build", "bun_bundle", "bun_compile")
 load("@rules_shell//shell:sh_test.bzl", "sh_test")
+load("//bun:defs.bzl", "bun_build", "bun_bundle", "bun_compile")

 bun_bundle(
    name = "simple_bundle",
@@ -18,64 +18,53 @@ bun_bundle(
    external = ["left-pad"],
 )

+bun_bundle(
+    name = "collision_bundle",
+    entry_points = [
+        "collision_case/a/main.ts",
+        "collision_case/b/main.ts",
+    ],
+)
+
 bun_build(
    name = "site_build",
-    entry_points = ["site/index.html"],
    data = [
        "site/main.ts",
        "site/styles.css",
    ],
+    entry_points = ["site/index.html"],
    splitting = True,
 )

 bun_build(
    name = "site_build_with_meta",
-    entry_points = ["site/index.html"],
    data = [
        "site/main.ts",
        "site/styles.css",
    ],
+    entry_points = ["site/index.html"],
    metafile = True,
    metafile_md = True,
 )

 bun_build(
    name = "advanced_site_build",
-    tags = ["manual"],
-    entry_points = ["site/index.html"],
-    data = [
-        "site/main.ts",
-        "site/styles.css",
-    ],
-    install_mode = "fallback",
-    target = "node",
-    format = "cjs",
-    production = True,
-    splitting = True,
-    root = "tests/bundle_test/site",
-    sourcemap = "linked",
-    banner = "/* bundle banner */",
-    footer = "// bundle footer",
-    public_path = "/static/",
-    packages = "external",
-    external = [
-        "left-pad",
-        "react",
-    ],
-    entry_naming = "entries/[name]-[hash].[ext]",
-    chunk_naming = "chunks/[name]-[hash].[ext]",
    asset_naming = "assets/[name]-[hash].[ext]",
-    minify = True,
-    minify_syntax = True,
-    minify_whitespace = True,
-    minify_identifiers = True,
-    keep_names = True,
-    css_chunking = True,
+    banner = "/* bundle banner */",
+    build_flags = [
+        "--app",
+        "--server-components",
+    ],
+    chunk_naming = "chunks/[name]-[hash].[ext]",
    conditions = [
        "browser",
        "custom",
    ],
-    env = "PUBLIC_*",
+    css_chunking = True,
+    data = [
+        "site/main.ts",
+        "site/styles.css",
+    ],
    define = [
        "process.env.NODE_ENV:\"production\"",
        "__DEV__:false",
@@ -84,26 +73,44 @@ bun_build(
        "console",
        "debugger",
    ],
+    emit_dce_annotations = True,
+    entry_naming = "entries/[name]-[hash].[ext]",
+    entry_points = ["site/index.html"],
+    env = "PUBLIC_*",
+    external = [
+        "left-pad",
+        "react",
+    ],
    feature = [
        "react_fast_refresh",
        "server_components",
    ],
-    loader = [
-        ".svg:file",
-        ".txt:text",
-    ],
+    footer = "// bundle footer",
+    format = "cjs",
    jsx_factory = "h",
    jsx_fragment = "Fragment",
    jsx_import_source = "preact",
    jsx_runtime = "automatic",
    jsx_side_effects = True,
-    react_fast_refresh = True,
-    emit_dce_annotations = True,
-    no_bundle = True,
-    build_flags = [
-        "--app",
-        "--server-components",
+    keep_names = True,
+    loader = [
+        ".svg:file",
+        ".txt:text",
    ],
+    minify = True,
+    minify_identifiers = True,
+    minify_syntax = True,
+    minify_whitespace = True,
+    no_bundle = True,
+    packages = "external",
+    production = True,
+    public_path = "/static/",
+    react_fast_refresh = True,
+    root = "tests/bundle_test/site",
+    sourcemap = "linked",
+    splitting = True,
+    tags = ["manual"],
+    target = "node",
 )

 bun_compile(
@@ -113,29 +120,30 @@ bun_compile(

 bun_compile(
    name = "compiled_cli_with_flags",
-    tags = ["manual"],
-    entry_point = "cli.ts",
    bytecode = True,
+    compile_autoload_bunfig = False,
+    compile_autoload_dotenv = False,
+    compile_autoload_package_json = True,
+    compile_autoload_tsconfig = True,
    compile_exec_argv = [
        "--smol",
        "--inspect-wait",
    ],
    compile_executable = "fake_cross_bun.bin",
-    compile_autoload_dotenv = False,
-    compile_autoload_bunfig = False,
-    compile_autoload_tsconfig = True,
-    compile_autoload_package_json = True,
+    entry_point = "cli.ts",
+    tags = ["manual"],
+    windows_copyright = "(c) rules_bun",
+    windows_description = "compile flag coverage",
    windows_hide_console = True,
    windows_icon = "branding/icon.ico",
-    windows_title = "Rules Bun Test App",
    windows_publisher = "rules_bun",
+    windows_title = "Rules Bun Test App",
    windows_version = "1.2.3.4",
-    windows_description = "compile flag coverage",
-    windows_copyright = "(c) rules_bun",
 )

 sh_test(
    name = "bundle_output_test",
+    size = "small",
    srcs = ["verify_bundle.sh"],
    args = ["$(location :simple_bundle)"],
    data = [":simple_bundle"],
@@ -143,19 +151,21 @@ sh_test(

 sh_test(
    name = "bundle_minify_test",
+    size = "small",
    srcs = ["verify_minify.sh"],
    args = [
        "$(location :simple_bundle)",
        "$(location :minified_bundle)",
    ],
    data = [
-        ":simple_bundle",
        ":minified_bundle",
+        ":simple_bundle",
    ],
 )

 sh_test(
    name = "bundle_hermetic_digest_test",
+    size = "small",
    srcs = ["verify_hermetic_shape.sh"],
    args = ["$(location //internal:bun_bundle.bzl)"],
    data = ["//internal:bun_bundle.bzl"],
@@ -163,6 +173,7 @@ sh_test(

 sh_test(
    name = "bundle_external_exclusion_test",
+    size = "small",
    srcs = ["verify_external_shape.sh"],
    args = [
        "$(location //internal:bun_bundle.bzl)",
@@ -174,22 +185,32 @@ sh_test(
    ],
 )

+sh_test(
+    name = "bundle_collision_output_test",
+    size = "small",
+    srcs = ["verify_collision_outputs.sh"],
+    args = ["$(locations :collision_bundle)"],
+    data = [":collision_bundle"],
+)
+
 sh_test(
    name = "bundle_sourcemap_shape_test",
+    size = "small",
    srcs = ["verify_sourcemap_shape.sh"],
-    env_inherit = ["PATH"],
    data = [
+        "BUILD.bazel",
        "//:repo_runtime_files",
        "//bun:repo_runtime_files",
        "//internal:repo_runtime_files",
-        "BUILD.bazel",
        "//tests/bundle_test/sourcemap_case:BUILD.bazel",
        "//tests/bundle_test/sourcemap_case:entry.ts",
    ],
+    env_inherit = ["PATH"],
 )

 sh_test(
    name = "bun_build_site_output_test",
+    size = "small",
    srcs = ["verify_site_build.sh"],
    args = ["$(location :site_build)"],
    data = [":site_build"],
@@ -197,6 +218,7 @@ sh_test(

 sh_test(
    name = "bun_build_site_meta_test",
+    size = "small",
    srcs = ["verify_site_build_meta.sh"],
    args = ["$(locations :site_build_with_meta)"],
    data = [":site_build_with_meta"],
@@ -204,6 +226,7 @@ sh_test(

 sh_test(
    name = "bun_compile_output_test",
+    size = "small",
    srcs = ["run_compiled_binary.sh"],
    args = ["$(location :compiled_cli)"],
    data = [":compiled_cli"],
@@ -211,17 +234,18 @@ sh_test(

 sh_test(
    name = "bun_build_compile_flag_shape_test",
+    size = "small",
    srcs = ["verify_flag_aquery.sh"],
-    env_inherit = ["PATH"],
    data = [
-        "//:repo_runtime_files",
-        "//bun:repo_runtime_files",
-        "//internal:repo_runtime_files",
        "BUILD.bazel",
        "cli.ts",
        "fake_cross_bun.bin",
        "site/index.html",
        "site/main.ts",
        "site/styles.css",
+        "//:repo_runtime_files",
+        "//bun:repo_runtime_files",
+        "//internal:repo_runtime_files",
    ],
+    env_inherit = ["PATH"],
 )
--- a/tests/bundle_test/collision_case/a/main.ts
+++ b/tests/bundle_test/collision_case/a/main.ts
@@ -0,0 +1 @@
+console.log("a");
--- a/tests/bundle_test/collision_case/b/main.ts
+++ b/tests/bundle_test/collision_case/b/main.ts
@@ -0,0 +1 @@
+console.log("b");
--- a/tests/bundle_test/verify_collision_outputs.sh
+++ b/tests/bundle_test/verify_collision_outputs.sh
@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+first_output="$1"
+second_output="$2"
+
+if [[ ${first_output} == "${second_output}" ]]; then
+  echo "Expected distinct bundle outputs for same-basename entry points" >&2
+  exit 1
+fi
+
+if [[ ! -f ${first_output} || ! -f ${second_output} ]]; then
+  echo "Expected both bundle outputs to exist" >&2
+  exit 1
+fi
+
+if [[ ${first_output} != *"collision_bundle__tests_bundle_test_collision_case_a_main.js" ]]; then
+  echo "Unexpected first output path: ${first_output}" >&2
+  exit 1
+fi
+
+if [[ ${second_output} != *"collision_bundle__tests_bundle_test_collision_case_b_main.js" ]]; then
+  echo "Unexpected second output path: ${second_output}" >&2
+  exit 1
+fi
--- a/tests/bundle_test/verify_flag_aquery.sh
+++ b/tests/bundle_test/verify_flag_aquery.sh
@@ -68,8 +68,6 @@ expect_line() {
 build_output="$(run_aquery "BunBuild" "//tests/bundle_test:advanced_site_build")"

 for expected in \
-  'arguments: "--install"' \
-  'arguments: "fallback"' \
  'arguments: "--target"' \
  'arguments: "node"' \
  'arguments: "--format"' \
--- a/tests/bundle_test/verify_hermetic_shape.sh
+++ b/tests/bundle_test/verify_hermetic_shape.sh
@@ -4,6 +4,6 @@ set -euo pipefail
 rule_file="$1"

 grep -Fq 'def _output_name(target_name, entry):' "${rule_file}"
-grep -Fq 'return "{}__{}.js".format(target_name, stem)' "${rule_file}"
-grep -Fq 'inputs = depset(' "${rule_file}"
-grep -Fq 'direct = [entry] + ctx.files.data' "${rule_file}"
+grep -Fq 'stem = entry.short_path.rsplit(".", 1)[0]' "${rule_file}"
+grep -Fq 'validate_hermetic_install_mode(ctx.attr, "bun_bundle")' "${rule_file}"
+grep -Fq 'declare_staged_bun_build_action(' "${rule_file}"
--- a/tests/ci_test/BUILD.bazel
+++ b/tests/ci_test/BUILD.bazel
@@ -2,7 +2,26 @@ load("@rules_shell//shell:sh_test.bzl", "sh_test")

 sh_test(
    name = "phase8_ci_matrix_shape_test",
+    size = "small",
    srcs = ["phase8_ci_matrix_shape_test.sh"],
    args = ["$(location //.github/workflows:ci.yml)"],
    data = ["//.github/workflows:ci.yml"],
 )
+
+sh_test(
+    name = "native_wrapper_shape_test",
+    size = "small",
+    srcs = ["verify_native_wrapper_shape.sh"],
+    args = [
+        "$(location //tests/binary_test:configured_launcher_bin)",
+        "$(location //tests/script_test:workspace_flagged_script)",
+        "$(location //tests/js_compat_test:compat_devserver)",
+        "$(location //tests/bun_test_test:configured_suite)",
+    ],
+    data = [
+        "//tests/binary_test:configured_launcher_bin",
+        "//tests/bun_test_test:configured_suite",
+        "//tests/js_compat_test:compat_devserver",
+        "//tests/script_test:workspace_flagged_script",
+    ],
+)
--- a/tests/ci_test/verify_native_wrapper_shape.sh
+++ b/tests/ci_test/verify_native_wrapper_shape.sh
@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+python3 - "$@" <<'PY'
+import pathlib
+import sys
+
+windows = sys.platform.startswith("win")
+
+for launcher in sys.argv[1:]:
+    suffix = pathlib.Path(launcher).suffix.lower()
+    if windows:
+        if suffix != ".cmd":
+            raise SystemExit(f"expected .cmd launcher on Windows: {launcher}")
+    elif suffix == ".sh":
+        raise SystemExit(f"unexpected .sh launcher executable: {launcher}")
+PY
--- a/tests/install_extension_test/BUILD.bazel
+++ b/tests/install_extension_test/BUILD.bazel
@@ -2,6 +2,7 @@ load("@rules_shell//shell:sh_test.bzl", "sh_test")

 sh_test(
    name = "bun_install_extension_shape_test",
+    size = "small",
    srcs = ["extension_shape_test.sh"],
    args = ["$(location //bun:extensions.bzl)"],
    data = ["//bun:extensions.bzl"],
@@ -9,6 +10,7 @@ sh_test(

 sh_test(
    name = "npm_translate_lock_extension_shape_test",
+    size = "small",
    srcs = ["npm_extension_shape_test.sh"],
    args = ["$(location //npm:extensions.bzl)"],
    data = ["//npm:extensions.bzl"],
--- a/tests/install_extension_test/extension_shape_test.sh
+++ b/tests/install_extension_test/extension_shape_test.sh
@@ -10,3 +10,4 @@ grep -Eq '"package_json":[[:space:]]*attr\.label\(mandatory[[:space:]]*=[[:space
 grep -Eq '"bun_lockfile":[[:space:]]*attr\.label\(mandatory[[:space:]]*=[[:space:]]*True\)' "${extension_file}"
 grep -Eq '"install_inputs":[[:space:]]*attr\.label_list\(allow_files[[:space:]]*=[[:space:]]*True\)' "${extension_file}"
 grep -Eq '"isolated_home":[[:space:]]*attr\.bool\(default[[:space:]]*=[[:space:]]*True\)' "${extension_file}"
+grep -Eq '"ignore_scripts":[[:space:]]*attr\.bool\(default[[:space:]]*=[[:space:]]*True\)' "${extension_file}"
--- a/tests/install_test/BUILD.bazel
+++ b/tests/install_test/BUILD.bazel
@@ -34,6 +34,7 @@ config_setting(

 sh_test(
    name = "bun_install_clean_install_test",
+    size = "small",
    srcs = ["clean_install.sh"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
@@ -53,6 +54,7 @@ sh_test(

 sh_test(
    name = "bun_install_stale_lockfile_test",
+    size = "small",
    srcs = ["stale_lockfile.sh"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
@@ -72,6 +74,7 @@ sh_test(

 sh_test(
    name = "bun_install_determinism_test",
+    size = "small",
    srcs = ["determinism.sh"],
    args = ["$(location //internal:bun_install.bzl)"],
    data = ["//internal:bun_install.bzl"],
@@ -79,6 +82,7 @@ sh_test(

 sh_test(
    name = "bun_install_environment_shape_test",
+    size = "small",
    srcs = ["environment_shape.sh"],
    args = ["$(location //internal:bun_install.bzl)"],
    data = ["//internal:bun_install.bzl"],
@@ -86,6 +90,7 @@ sh_test(

 sh_test(
    name = "bun_install_workspaces_test",
+    size = "small",
    srcs = ["workspaces.sh"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
@@ -105,6 +110,7 @@ sh_test(

 sh_test(
    name = "bun_install_workspaces_catalog_test",
+    size = "small",
    srcs = ["workspaces_catalog.sh"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
@@ -125,7 +131,6 @@ sh_test(
 sh_test(
    name = "bun_install_workspace_parity_test",
    srcs = ["workspace_parity.sh"],
-    env_inherit = ["PATH"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
        ":linux_aarch64": ["$(location @bun_linux_aarch64//:bun)"],
@@ -144,11 +149,63 @@ sh_test(
        "//bun:repo_runtime_files",
        "//internal:repo_runtime_files",
    ],
+    env_inherit = ["PATH"],
 )

 sh_test(
    name = "bun_install_install_flags_shape_test",
+    size = "small",
    srcs = ["install_flags_shape.sh"],
    args = ["$(location //internal:bun_install.bzl)"],
    data = ["//internal:bun_install.bzl"],
 )
+
+sh_test(
+    name = "bun_install_repeatability_test",
+    size = "small",
+    srcs = ["repeatability.sh"],
+    args = select({
+        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
+        ":linux_aarch64": ["$(location @bun_linux_aarch64//:bun)"],
+        ":darwin_x86_64": ["$(location @bun_darwin_x64//:bun)"],
+        ":darwin_aarch64": ["$(location @bun_darwin_aarch64//:bun)"],
+        "//conditions:default": ["$(location @bun_linux_x64//:bun)"],
+    }),
+    data = select({
+        ":linux_x86_64": ["@bun_linux_x64//:bun"],
+        ":linux_aarch64": ["@bun_linux_aarch64//:bun"],
+        ":darwin_x86_64": ["@bun_darwin_x64//:bun"],
+        ":darwin_aarch64": ["@bun_darwin_aarch64//:bun"],
+        "//conditions:default": ["@bun_linux_x64//:bun"],
+    }) + [
+        "//:repo_runtime_files",
+        "//bun:repo_runtime_files",
+        "//internal:repo_runtime_files",
+    ],
+    env_inherit = ["PATH"],
+)
+
+sh_test(
+    name = "bun_install_lifecycle_scripts_test",
+    size = "small",
+    srcs = ["lifecycle_scripts.sh"],
+    args = select({
+        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
+        ":linux_aarch64": ["$(location @bun_linux_aarch64//:bun)"],
+        ":darwin_x86_64": ["$(location @bun_darwin_x64//:bun)"],
+        ":darwin_aarch64": ["$(location @bun_darwin_aarch64//:bun)"],
+        "//conditions:default": ["$(location @bun_linux_x64//:bun)"],
+    }),
+    data = select({
+        ":linux_x86_64": ["@bun_linux_x64//:bun"],
+        ":linux_aarch64": ["@bun_linux_aarch64//:bun"],
+        ":darwin_x86_64": ["@bun_darwin_x64//:bun"],
+        ":darwin_aarch64": ["@bun_darwin_aarch64//:bun"],
+        "//conditions:default": ["@bun_linux_x64//:bun"],
+    }) + [
+        "//:repo_runtime_files",
+        "//bun:repo_runtime_files",
+        "//internal:repo_runtime_files",
+    ],
+    env_inherit = ["PATH"],
+)
--- a/tests/install_test/lifecycle_scripts.sh
+++ b/tests/install_test/lifecycle_scripts.sh
@@ -0,0 +1,118 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+bun_path="$1"
+
+if command -v bazel >/dev/null 2>&1; then
+  bazel_cmd=(bazel)
+elif command -v bazelisk >/dev/null 2>&1; then
+  bazel_cmd=(bazelisk)
+else
+  echo "bazel or bazelisk is required on PATH" >&2
+  exit 1
+fi
+
+script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd -P)"
+rules_bun_root="$(cd "${script_dir}/../.." && pwd -P)"
+
+workdir="$(mktemp -d)"
+trap 'rm -rf "${workdir}"' EXIT
+
+fixture_dir="${workdir}/fixture"
+mkdir -p "${fixture_dir}"
+
+cat >"${fixture_dir}/package.json" <<'JSON'
+{
+  "name": "lifecycle-script-test",
+  "version": "1.0.0",
+  "dependencies": {
+    "is-number": "7.0.0"
+  },
+  "scripts": {
+    "postinstall": "bun -e \"require('node:fs').writeFileSync('postinstall.txt', 'ran')\""
+  }
+}
+JSON
+
+"${bun_path}" install --cwd "${fixture_dir}" >/dev/null
+rm -rf "${fixture_dir}/node_modules" "${fixture_dir}/postinstall.txt"
+
+cat >"${fixture_dir}/MODULE.bazel" <<EOF
+module(
+    name = "bun_install_lifecycle_scripts_test",
+)
+
+bazel_dep(name = "rules_bun", version = "0.2.2")
+
+local_path_override(
+    module_name = "rules_bun",
+    path = "${rules_bun_root}",
+)
+
+bun_ext = use_extension("@rules_bun//bun:extensions.bzl", "bun")
+use_repo(
+    bun_ext,
+    "bun_darwin_aarch64",
+    "bun_darwin_x64",
+    "bun_linux_aarch64",
+    "bun_linux_x64",
+    "bun_windows_x64",
+)
+
+bun_install_ext = use_extension("@rules_bun//bun:extensions.bzl", "bun_install")
+bun_install_ext.install(
+    name = "scripts_blocked",
+    package_json = "//:package.json",
+    bun_lockfile = "//:bun.lock",
+)
+bun_install_ext.install(
+    name = "scripts_allowed",
+    package_json = "//:package.json",
+    bun_lockfile = "//:bun.lock",
+    ignore_scripts = False,
+)
+use_repo(
+    bun_install_ext,
+    "scripts_allowed",
+    "scripts_blocked",
+)
+
+register_toolchains(
+    "@rules_bun//bun:darwin_aarch64_toolchain",
+    "@rules_bun//bun:darwin_x64_toolchain",
+    "@rules_bun//bun:linux_aarch64_toolchain",
+    "@rules_bun//bun:linux_x64_toolchain",
+    "@rules_bun//bun:windows_x64_toolchain",
+)
+EOF
+
+cat >"${fixture_dir}/BUILD.bazel" <<'EOF'
+exports_files([
+    "package.json",
+    "bun.lock",
+])
+EOF
+
+(
+  cd "${fixture_dir}"
+  "${bazel_cmd[@]}" build @scripts_blocked//:node_modules @scripts_allowed//:node_modules >/dev/null
+)
+
+output_base="$(cd "${fixture_dir}" && "${bazel_cmd[@]}" info output_base)"
+blocked_repo="$(find "${output_base}/external" -maxdepth 1 -type d -name '*+scripts_blocked' | head -n 1)"
+allowed_repo="$(find "${output_base}/external" -maxdepth 1 -type d -name '*+scripts_allowed' | head -n 1)"
+
+if [[ -z ${blocked_repo} || -z ${allowed_repo} ]]; then
+  echo "Unable to locate generated lifecycle test repositories" >&2
+  exit 1
+fi
+
+if [[ -e "${blocked_repo}/postinstall.txt" ]]; then
+  echo "Lifecycle scripts should be disabled by default" >&2
+  exit 1
+fi
+
+if [[ ! -f "${allowed_repo}/postinstall.txt" ]]; then
+  echo "Lifecycle scripts should run when ignore_scripts = False" >&2
+  exit 1
+fi
--- a/tests/install_test/repeatability.sh
+++ b/tests/install_test/repeatability.sh
@@ -0,0 +1,128 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+bun_path="$1"
+
+if command -v bazel >/dev/null 2>&1; then
+  bazel_cmd=(bazel)
+elif command -v bazelisk >/dev/null 2>&1; then
+  bazel_cmd=(bazelisk)
+else
+  echo "bazel or bazelisk is required on PATH" >&2
+  exit 1
+fi
+
+script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd -P)"
+rules_bun_root="$(cd "${script_dir}/../.." && pwd -P)"
+
+workdir="$(mktemp -d)"
+trap 'rm -rf "${workdir}"' EXIT
+
+fixture_dir="${workdir}/fixture"
+mkdir -p "${fixture_dir}"
+
+cat >"${fixture_dir}/package.json" <<'JSON'
+{
+  "name": "repeatability-test",
+  "version": "1.0.0",
+  "dependencies": {
+    "is-number": "7.0.0"
+  }
+}
+JSON
+
+"${bun_path}" install --cwd "${fixture_dir}" >/dev/null
+rm -rf "${fixture_dir}/node_modules"
+
+cat >"${fixture_dir}/MODULE.bazel" <<EOF
+module(
+    name = "bun_install_repeatability_test",
+)
+
+bazel_dep(name = "rules_bun", version = "0.2.2")
+
+local_path_override(
+    module_name = "rules_bun",
+    path = "${rules_bun_root}",
+)
+
+bun_ext = use_extension("@rules_bun//bun:extensions.bzl", "bun")
+use_repo(
+    bun_ext,
+    "bun_darwin_aarch64",
+    "bun_darwin_x64",
+    "bun_linux_aarch64",
+    "bun_linux_x64",
+    "bun_windows_x64",
+)
+
+bun_install_ext = use_extension("@rules_bun//bun:extensions.bzl", "bun_install")
+bun_install_ext.install(
+    name = "node_modules_a",
+    package_json = "//:package.json",
+    bun_lockfile = "//:bun.lock",
+)
+bun_install_ext.install(
+    name = "node_modules_b",
+    package_json = "//:package.json",
+    bun_lockfile = "//:bun.lock",
+)
+use_repo(
+    bun_install_ext,
+    "node_modules_a",
+    "node_modules_b",
+)
+
+register_toolchains(
+    "@rules_bun//bun:darwin_aarch64_toolchain",
+    "@rules_bun//bun:darwin_x64_toolchain",
+    "@rules_bun//bun:linux_aarch64_toolchain",
+    "@rules_bun//bun:linux_x64_toolchain",
+    "@rules_bun//bun:windows_x64_toolchain",
+)
+EOF
+
+cat >"${fixture_dir}/BUILD.bazel" <<'EOF'
+exports_files([
+    "package.json",
+    "bun.lock",
+])
+EOF
+
+(
+  cd "${fixture_dir}"
+  "${bazel_cmd[@]}" build @node_modules_a//:node_modules @node_modules_b//:node_modules >/dev/null
+)
+
+output_base="$(cd "${fixture_dir}" && "${bazel_cmd[@]}" info output_base)"
+repo_a="$(find "${output_base}/external" -maxdepth 1 -type d -name '*+node_modules_a' | head -n 1)"
+repo_b="$(find "${output_base}/external" -maxdepth 1 -type d -name '*+node_modules_b' | head -n 1)"
+
+if [[ -z ${repo_a} || -z ${repo_b} ]]; then
+  echo "Unable to locate generated node_modules repositories" >&2
+  exit 1
+fi
+
+snapshot_tree() {
+  local root="$1"
+  (
+    cd "${root}"
+    while IFS= read -r -d '' path; do
+      local rel="${path#./}"
+      if [[ -L ${path} ]]; then
+        local target
+        target="$(readlink "${path}")"
+        target="${target//node_modules_a/node_modules}"
+        target="${target//node_modules_b/node_modules}"
+        printf 'L %s %s\n' "${rel}" "${target}"
+      else
+        printf 'F %s %s\n' "${rel}" "$(shasum -a 256 "${path}" | awk '{print $1}')"
+      fi
+    done < <(find . \( -type f -o -type l \) -print0 | sort -z)
+  )
+}
+
+snapshot_tree "${repo_a}/node_modules" >"${workdir}/repo_a.snapshot"
+snapshot_tree "${repo_b}/node_modules" >"${workdir}/repo_b.snapshot"
+
+diff -u "${workdir}/repo_a.snapshot" "${workdir}/repo_b.snapshot"
--- a/tests/install_test/workspaces.sh
+++ b/tests/install_test/workspaces.sh
@@ -2,6 +2,9 @@
 set -euo pipefail

 bun_path="$1"
+if [[ ${bun_path} != /* ]]; then
+  bun_path="$(cd "$(dirname "${bun_path}")" && pwd -P)/$(basename "${bun_path}")"
+fi
 workdir="$(mktemp -d)"
 trap 'rm -rf "${workdir}"' EXIT

--- a/tests/install_test/workspaces_catalog.sh
+++ b/tests/install_test/workspaces_catalog.sh
@@ -2,6 +2,9 @@
 set -euo pipefail

 bun_path="$1"
+if [[ ${bun_path} != /* ]]; then
+  bun_path="$(cd "$(dirname "${bun_path}")" && pwd -P)/$(basename "${bun_path}")"
+fi
 workdir="$(mktemp -d)"
 trap 'rm -rf "${workdir}"' EXIT

--- a/tests/integration_test/BUILD.bazel
+++ b/tests/integration_test/BUILD.bazel
@@ -3,17 +3,18 @@ load("@rules_shell//shell:sh_test.bzl", "sh_test")
 test_suite(
    name = "examples_test",
    tests = [
-        ":examples_basic_run_e2e_test",
        ":examples_basic_hot_restart_shape_test",
-        ":examples_workspace_bundle_e2e_test",
-        ":examples_workspace_catalog_shape_test",
+        ":examples_basic_run_e2e_test",
        ":examples_vite_monorepo_catalog_shape_test",
        ":examples_vite_monorepo_e2e_test",
+        ":examples_workspace_bundle_e2e_test",
+        ":examples_workspace_catalog_shape_test",
    ],
 )

 sh_test(
    name = "examples_basic_e2e_build_test",
+    size = "small",
    srcs = ["examples_basic_e2e_build_test.sh"],
    args = [
        "$(location //examples/basic:BUILD.bazel)",
@@ -27,6 +28,7 @@ sh_test(

 sh_test(
    name = "examples_basic_run_e2e_test",
+    size = "small",
    srcs = ["examples_basic_run_e2e_test.sh"],
    args = ["$(location //examples/basic:web_dev)"],
    data = ["//examples/basic:web_dev"],
@@ -34,6 +36,7 @@ sh_test(

 sh_test(
    name = "examples_basic_hot_restart_shape_test",
+    size = "small",
    srcs = ["examples_basic_hot_restart_shape_test.sh"],
    args = ["$(location //examples/basic:web_dev_hot_restart)"],
    data = ["//examples/basic:web_dev_hot_restart"],
@@ -41,6 +44,7 @@ sh_test(

 sh_test(
    name = "examples_workspace_bundle_e2e_test",
+    size = "small",
    srcs = ["examples_workspace_bundle_e2e_test.sh"],
    args = ["$(location //examples/workspace:pkg_b_bundle)"],
    data = ["//examples/workspace:pkg_b_bundle"],
@@ -48,6 +52,7 @@ sh_test(

 sh_test(
    name = "examples_workspace_catalog_shape_test",
+    size = "small",
    srcs = ["examples_workspace_catalog_shape_test.sh"],
    args = [
        "$(location //examples/workspace:package.json)",
@@ -63,6 +68,7 @@ sh_test(

 sh_test(
    name = "examples_vite_monorepo_catalog_shape_test",
+    size = "small",
    srcs = ["examples_vite_monorepo_catalog_shape_test.sh"],
    args = [
        "$(location //examples/vite_monorepo:package.json)",
@@ -70,14 +76,15 @@ sh_test(
        "$(location //examples/vite_monorepo:apps/app-b/package.json)",
    ],
    data = [
-        "//examples/vite_monorepo:package.json",
        "//examples/vite_monorepo:apps/app-a/package.json",
        "//examples/vite_monorepo:apps/app-b/package.json",
+        "//examples/vite_monorepo:package.json",
    ],
 )

 sh_test(
    name = "examples_vite_monorepo_e2e_test",
+    size = "small",
    srcs = ["examples_vite_monorepo_e2e_test.sh"],
    args = [
        "$(location //examples/vite_monorepo:app_a_dev)",
@@ -91,6 +98,7 @@ sh_test(

 sh_test(
    name = "repo_all_targets_test",
+    size = "small",
    srcs = ["repo_all_targets_test.sh"],
    args = ["$(location //.github/workflows:ci.yml)"],
    data = ["//.github/workflows:ci.yml"],
--- a/tests/integration_test/examples_basic_hot_restart_shape_test.sh
+++ b/tests/integration_test/examples_basic_hot_restart_shape_test.sh
@@ -1,11 +1,21 @@
 #!/usr/bin/env bash
 set -euo pipefail

-binary="$1"
+launcher="$1"

-grep -Fq -- 'watch_mode="hot"' "${binary}"
-grep -Fq -- 'bun_args+=("--hot")' "${binary}"
-grep -Fq -- '--no-clear-screen' "${binary}"
-grep -Fq -- 'if [[ 1 -eq 0 ]]; then' "${binary}"
-grep -Fq -- 'readarray -t restart_paths' "${binary}"
-grep -Fq -- 'examples/basic/README.md' "${binary}"
+python3 - "${launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+assert spec["kind"] == "bun_run", spec
+assert spec["watch_mode"] == "hot", spec
+assert "--no-clear-screen" in spec["argv"], spec
+assert spec["restart_on"], spec
+assert spec["restart_on"][0].endswith("examples/basic/README.md"), spec
+PY
--- a/tests/integration_test/examples_basic_run_e2e_test.sh
+++ b/tests/integration_test/examples_basic_run_e2e_test.sh
@@ -14,8 +14,24 @@ cleanup() {
 }
 trap cleanup EXIT

-"${binary}" >"${log_file}" 2>&1 &
+start_launcher() {
+  local launcher="$1"
+  local log_target="$2"
+  shift 2
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" >"${log_target}" 2>&1 &
+  else
+    "${launcher}" "$@" >"${log_target}" 2>&1 &
+  fi
  server_pid=$!
+}
+
+start_launcher "${binary}" "${log_file}"

 for _ in {1..20}; do
  if grep -Fq "rules_bun bun_dev example" "${log_file}"; then
--- a/tests/integration_test/examples_vite_monorepo_e2e_test.sh
+++ b/tests/integration_test/examples_vite_monorepo_e2e_test.sh
@@ -17,6 +17,23 @@ cleanup() {
 }
 trap cleanup EXIT

+start_launcher() {
+  local launcher="$1"
+  local log_target="$2"
+  shift 2
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" >"${log_target}" 2>&1 &
+  else
+    "${launcher}" "$@" >"${log_target}" 2>&1 &
+  fi
+  server_pid=$!
+}
+
 pick_port() {
  python3 - <<'PY'
 import socket
@@ -37,8 +54,7 @@ verify_vite_app() {
  port="$(pick_port)"
  log_file="${workdir}/${log_name}.log"

-  "${binary}" --host 127.0.0.1 --port "${port}" --strictPort >"${log_file}" 2>&1 &
-  server_pid=$!
+  start_launcher "${binary}" "${log_file}" --host 127.0.0.1 --port "${port}" --strictPort

  for _ in {1..60}; do
    if ! kill -0 "${server_pid}" 2>/dev/null; then
--- a/tests/js_compat_test/BUILD.bazel
+++ b/tests/js_compat_test/BUILD.bazel
@@ -1,5 +1,5 @@
-load("//js:defs.bzl", "js_binary", "js_run_devserver", "js_test", "ts_library")
 load("@rules_shell//shell:sh_test.bzl", "sh_test")
+load("//js:defs.bzl", "js_binary", "js_run_devserver", "js_test", "ts_library")

 ts_library(
    name = "helper_lib",
@@ -9,13 +9,14 @@ ts_library(

 js_binary(
    name = "compat_bin",
+    args = ["compat-mode"],
    entry_point = "main.ts",
    deps = [":helper_lib"],
-    args = ["compat-mode"],
 )

 sh_test(
    name = "js_binary_compat_test",
+    size = "small",
    srcs = ["run_binary.sh"],
    args = ["$(location :compat_bin)"],
    data = [":compat_bin"],
@@ -23,18 +24,21 @@ sh_test(

 js_test(
    name = "compat_suite",
+    size = "small",
    entry_point = "app.test.ts",
    deps = [":helper_lib"],
 )

 js_run_devserver(
    name = "compat_devserver",
-    tool = ":compat_bin",
    args = ["devserver-mode"],
+    tool = ":compat_bin",
+    visibility = ["//tests/ci_test:__pkg__"],
 )

 sh_test(
    name = "js_run_devserver_compat_test",
+    size = "small",
    srcs = ["run_devserver.sh"],
    args = ["$(location :compat_devserver)"],
    data = [":compat_devserver"],
@@ -42,27 +46,28 @@ sh_test(

 js_run_devserver(
    name = "compat_devserver_with_package_json",
-    tool = ":compat_bin",
    package_json = "app/package.json",
+    tool = ":compat_bin",
    working_dir = "package",
 )

 js_run_devserver(
    name = "compat_devserver_with_package_dir_hint",
-    tool = ":compat_bin",
    package_dir_hint = "app",
+    tool = ":compat_bin",
    working_dir = "package",
 )

 sh_test(
    name = "js_run_devserver_workspace_shape_test",
+    size = "small",
    srcs = ["verify_workspace_shape.sh"],
    args = [
        "$(location :compat_devserver_with_package_json)",
        "$(location :compat_devserver_with_package_dir_hint)",
    ],
    data = [
-        ":compat_devserver_with_package_json",
        ":compat_devserver_with_package_dir_hint",
+        ":compat_devserver_with_package_json",
    ],
 )
--- a/tests/js_compat_test/run_binary.sh
+++ b/tests/js_compat_test/run_binary.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$("${binary}")"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "helper:payload-from-lib compat-mode" ]]; then
  echo "unexpected output: ${output}" >&2
--- a/tests/js_compat_test/run_devserver.sh
+++ b/tests/js_compat_test/run_devserver.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$("${binary}")"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "helper:payload-from-lib compat-mode devserver-mode" ]]; then
  echo "unexpected output: ${output}" >&2
--- a/tests/js_compat_test/verify_workspace_shape.sh
+++ b/tests/js_compat_test/verify_workspace_shape.sh
@@ -4,10 +4,25 @@ set -euo pipefail
 package_json_launcher="$1"
 package_dir_hint_launcher="$2"

-grep -Fq -- 'package_json="${runfiles_dir}/_main/tests/js_compat_test/app/package.json"' "${package_json_launcher}"
-grep -Fq -- 'package_rel_dir_hint="."' "${package_json_launcher}"
-grep -Fq -- 'working_dir_mode="package"' "${package_json_launcher}"
+python3 - "${package_json_launcher}" "${package_dir_hint_launcher}" <<'PY'
+import json
+import pathlib
+import sys

-grep -Fq -- 'package_json=""' "${package_dir_hint_launcher}"
-grep -Fq -- 'package_rel_dir_hint="app"' "${package_dir_hint_launcher}"
-grep -Fq -- 'working_dir_mode="package"' "${package_dir_hint_launcher}"
+def read_spec(launcher: str):
+    path = pathlib.Path(launcher)
+    if path.suffix.lower() == ".cmd":
+        path = pathlib.Path(str(path)[:-4])
+    return json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+package_json_spec = read_spec(sys.argv[1])
+package_dir_hint_spec = read_spec(sys.argv[2])
+
+assert package_json_spec["package_json_short_path"].endswith("tests/js_compat_test/app/package.json"), package_json_spec
+assert package_json_spec["package_dir_hint"] == ".", package_json_spec
+assert package_json_spec["working_dir_mode"] == "package", package_json_spec
+
+assert package_dir_hint_spec["package_json_short_path"] == "", package_dir_hint_spec
+assert package_dir_hint_spec["package_dir_hint"] == "app", package_dir_hint_spec
+assert package_dir_hint_spec["working_dir_mode"] == "package", package_dir_hint_spec
+PY
--- a/tests/library_test/BUILD.bazel
+++ b/tests/library_test/BUILD.bazel
@@ -1,5 +1,5 @@
-load("//bun:defs.bzl", "bun_bundle", "bun_test", "ts_library")
 load("@rules_shell//shell:sh_test.bzl", "sh_test")
+load("//bun:defs.bzl", "bun_bundle", "bun_test", "ts_library")

 ts_library(
    name = "helper_lib",
@@ -14,6 +14,7 @@ bun_bundle(

 sh_test(
    name = "bundle_dep_propagation_test",
+    size = "small",
    srcs = ["verify_bundle.sh"],
    args = ["$(location :bundle_with_deps)"],
    data = [":bundle_with_deps"],
@@ -21,6 +22,7 @@ sh_test(

 bun_test(
    name = "test_with_deps",
+    size = "small",
    srcs = ["app.test.ts"],
    deps = [":helper_lib"],
 )
--- a/tests/npm_compat_test/BUILD.bazel
+++ b/tests/npm_compat_test/BUILD.bazel
@@ -34,8 +34,8 @@ config_setting(

 sh_test(
    name = "npm_translate_lock_workspace_test",
+    size = "small",
    srcs = ["npm_translate_lock_workspace_test.sh"],
-    env_inherit = ["PATH"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
        ":linux_aarch64": ["$(location @bun_linux_aarch64//:bun)"],
@@ -56,4 +56,5 @@ sh_test(
        "//js:repo_runtime_files",
        "//npm:repo_runtime_files",
    ],
+    env_inherit = ["PATH"],
 )
--- a/tests/script_test/BUILD.bazel
+++ b/tests/script_test/BUILD.bazel
@@ -1,32 +1,37 @@
-load("//bun:defs.bzl", "bun_script")
 load("@rules_shell//shell:sh_test.bzl", "sh_test")
+load("//bun:defs.bzl", "bun_script")

 bun_script(
    name = "hello_script",
-    script = "hello",
-    package_json = "package.json",
    data = ["hello.ts"],
+    package_json = "package.json",
+    script = "hello",
 )

 sh_test(
    name = "bun_script_ts_test",
+    size = "small",
    srcs = ["run_script.sh"],
-    args = ["$(location :hello_script)", "hello-script"],
+    args = [
+        "$(location :hello_script)",
+        "hello-script",
+    ],
    data = [":hello_script"],
 )

 bun_script(
    name = "env_script",
-    script = "print-env",
-    package_json = "package.json",
    data = [
        ".env",
        "env.ts",
    ],
+    package_json = "package.json",
+    script = "print-env",
 )

 sh_test(
    name = "bun_script_package_cwd_test",
+    size = "small",
    srcs = ["run_env_script.sh"],
    args = ["$(location :env_script)"],
    data = [":env_script"],
@@ -34,17 +39,18 @@ sh_test(

 bun_script(
    name = "vite_dev_server",
-    script = "dev",
-    package_json = "vite_app/package.json",
-    node_modules = "@script_test_vite_node_modules//:node_modules",
    data = [
        "vite_app/index.html",
        "vite_app/main.js",
    ],
+    node_modules = "@script_test_vite_node_modules//:node_modules",
+    package_json = "vite_app/package.json",
+    script = "dev",
 )

 sh_test(
    name = "bun_script_vite_app_test",
+    size = "small",
    srcs = ["run_vite_app.sh"],
    args = ["$(location :vite_dev_server)"],
    data = [":vite_dev_server"],
@@ -52,28 +58,29 @@ sh_test(

 bun_script(
    name = "vite_monorepo_app_a_dev_server",
-    script = "dev",
-    package_json = "vite_monorepo/apps/app-a/package.json",
-    node_modules = "@script_test_vite_monorepo_node_modules//:node_modules",
    data = [
        "vite_monorepo/apps/app-a/index.html",
        "vite_monorepo/apps/app-a/main.js",
    ],
+    node_modules = "@script_test_vite_monorepo_node_modules//:node_modules",
+    package_json = "vite_monorepo/apps/app-a/package.json",
+    script = "dev",
 )

 bun_script(
    name = "vite_monorepo_app_b_dev_server",
-    script = "dev",
-    package_json = "vite_monorepo/apps/app-b/package.json",
-    node_modules = "@script_test_vite_monorepo_node_modules//:node_modules",
    data = [
        "vite_monorepo/apps/app-b/index.html",
        "vite_monorepo/apps/app-b/main.js",
    ],
+    node_modules = "@script_test_vite_monorepo_node_modules//:node_modules",
+    package_json = "vite_monorepo/apps/app-b/package.json",
+    script = "dev",
 )

 sh_test(
    name = "bun_script_vite_monorepo_apps_test",
+    size = "small",
    srcs = ["run_vite_monorepo_apps.sh"],
    args = [
        "$(location :vite_monorepo_app_a_dev_server)",
@@ -85,54 +92,69 @@ sh_test(
    ],
 )

+sh_test(
+    name = "bun_script_monorepo_launcher_shape_test",
+    size = "small",
+    srcs = ["verify_monorepo_launcher_shape.sh"],
+    args = [
+        "$(location :vite_monorepo_app_a_dev_server)",
+        "$(location :paraglide_monorepo_app_a_build)",
+    ],
+    data = [
+        ":paraglide_monorepo_app_a_build",
+        ":vite_monorepo_app_a_dev_server",
+    ],
+)
+
 bun_script(
    name = "paraglide_monorepo_app_a_build",
-    script = "build:app-a",
-    package_json = "paraglide_monorepo/package.json",
-    node_modules = "@script_test_paraglide_monorepo_node_modules//:node_modules",
    data = [
-        "paraglide_monorepo/scripts/build-app-a.mjs",
-        "paraglide_monorepo/scripts/build-app-b.mjs",
-        "paraglide_monorepo/packages/i18n/package.json",
-        "paraglide_monorepo/packages/i18n/project.inlang/settings.json",
-        "paraglide_monorepo/packages/i18n/messages/en.json",
-        "paraglide_monorepo/packages/i18n/messages/sv.json",
-        "paraglide_monorepo/packages/app-a/package.json",
        "paraglide_monorepo/packages/app-a/index.html",
        "paraglide_monorepo/packages/app-a/main.js",
+        "paraglide_monorepo/packages/app-a/package.json",
        "paraglide_monorepo/packages/app-a/vite.config.js",
-        "paraglide_monorepo/packages/app-b/package.json",
        "paraglide_monorepo/packages/app-b/index.html",
        "paraglide_monorepo/packages/app-b/main.js",
+        "paraglide_monorepo/packages/app-b/package.json",
        "paraglide_monorepo/packages/app-b/vite.config.js",
+        "paraglide_monorepo/packages/i18n/messages/en.json",
+        "paraglide_monorepo/packages/i18n/messages/sv.json",
+        "paraglide_monorepo/packages/i18n/package.json",
+        "paraglide_monorepo/packages/i18n/project.inlang/settings.json",
+        "paraglide_monorepo/scripts/build-app-a.mjs",
+        "paraglide_monorepo/scripts/build-app-b.mjs",
    ],
+    node_modules = "@script_test_paraglide_monorepo_node_modules//:node_modules",
+    package_json = "paraglide_monorepo/package.json",
+    script = "build:app-a",
 )

 bun_script(
    name = "paraglide_monorepo_app_b_build",
-    script = "build:app-b",
-    package_json = "paraglide_monorepo/package.json",
-    node_modules = "@script_test_paraglide_monorepo_node_modules//:node_modules",
    data = [
-        "paraglide_monorepo/scripts/build-app-a.mjs",
-        "paraglide_monorepo/scripts/build-app-b.mjs",
-        "paraglide_monorepo/packages/i18n/package.json",
-        "paraglide_monorepo/packages/i18n/project.inlang/settings.json",
-        "paraglide_monorepo/packages/i18n/messages/en.json",
-        "paraglide_monorepo/packages/i18n/messages/sv.json",
-        "paraglide_monorepo/packages/app-a/package.json",
        "paraglide_monorepo/packages/app-a/index.html",
        "paraglide_monorepo/packages/app-a/main.js",
+        "paraglide_monorepo/packages/app-a/package.json",
        "paraglide_monorepo/packages/app-a/vite.config.js",
-        "paraglide_monorepo/packages/app-b/package.json",
        "paraglide_monorepo/packages/app-b/index.html",
        "paraglide_monorepo/packages/app-b/main.js",
+        "paraglide_monorepo/packages/app-b/package.json",
        "paraglide_monorepo/packages/app-b/vite.config.js",
+        "paraglide_monorepo/packages/i18n/messages/en.json",
+        "paraglide_monorepo/packages/i18n/messages/sv.json",
+        "paraglide_monorepo/packages/i18n/package.json",
+        "paraglide_monorepo/packages/i18n/project.inlang/settings.json",
+        "paraglide_monorepo/scripts/build-app-a.mjs",
+        "paraglide_monorepo/scripts/build-app-b.mjs",
    ],
+    node_modules = "@script_test_paraglide_monorepo_node_modules//:node_modules",
+    package_json = "paraglide_monorepo/package.json",
+    script = "build:app-b",
 )

 sh_test(
    name = "bun_script_paraglide_monorepo_build_test",
+    size = "small",
    srcs = ["run_paraglide_monorepo_builds.sh"],
    args = [
        "$(location :paraglide_monorepo_app_a_build)",
@@ -146,21 +168,22 @@ sh_test(

 bun_script(
    name = "workspace_filtered_script",
-    script = "say",
-    package_json = "workspace_run/package.json",
    data = [
        "workspace_run/packages/pkg-a/package.json",
        "workspace_run/packages/pkg-a/say.ts",
        "workspace_run/packages/pkg-b/package.json",
        "workspace_run/packages/pkg-b/say.ts",
    ],
-    filters = ["./packages/pkg-a"],
    execution_mode = "sequential",
+    filters = ["./packages/pkg-a"],
+    package_json = "workspace_run/package.json",
+    script = "say",
    silent = True,
 )

 sh_test(
    name = "bun_script_workspace_filter_test",
+    size = "small",
    srcs = ["run_workspace_script.sh"],
    args = ["$(location :workspace_filtered_script)"],
    data = [":workspace_filtered_script"],
@@ -168,20 +191,21 @@ sh_test(

 bun_script(
    name = "workspace_parallel_script",
-    script = "say",
-    package_json = "workspace_run/package.json",
    data = [
        "workspace_run/packages/pkg-a/package.json",
        "workspace_run/packages/pkg-a/say.ts",
        "workspace_run/packages/pkg-b/package.json",
        "workspace_run/packages/pkg-b/say.ts",
    ],
-    workspaces = True,
    execution_mode = "parallel",
+    package_json = "workspace_run/package.json",
+    script = "say",
+    workspaces = True,
 )

 sh_test(
    name = "bun_script_workspace_parallel_test",
+    size = "small",
    srcs = ["run_workspace_parallel.sh"],
    args = ["$(location :workspace_parallel_script)"],
    data = [":workspace_parallel_script"],
@@ -189,22 +213,24 @@ sh_test(

 bun_script(
    name = "workspace_flagged_script",
-    script = "say",
-    package_json = "workspace_run/package.json",
    data = [
        "workspace_run/packages/pkg-a/package.json",
        "workspace_run/packages/pkg-a/say.ts",
        "workspace_run/packages/pkg-b/package.json",
        "workspace_run/packages/pkg-b/say.ts",
    ],
-    workspaces = True,
    execution_mode = "parallel",
    no_exit_on_error = True,
+    package_json = "workspace_run/package.json",
+    script = "say",
    shell = "system",
+    visibility = ["//tests/ci_test:__pkg__"],
+    workspaces = True,
 )

 sh_test(
    name = "bun_script_workspace_flag_shape_test",
+    size = "small",
    srcs = ["verify_launcher_flags.sh"],
    args = [
        "$(location :workspace_flagged_script)",
--- a/tests/script_test/run_env_script.sh
+++ b/tests/script_test/run_env_script.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 binary="$1"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "from-dotenv" ]]; then
  echo "Expected .env value from package directory, got: ${output}" >&2
--- a/tests/script_test/run_paraglide_monorepo_builds.sh
+++ b/tests/script_test/run_paraglide_monorepo_builds.sh
@@ -10,13 +10,28 @@ cleanup() {
 }
 trap cleanup EXIT

+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
 verify_build() {
  local binary="$1"
  local out_dir="$2"
  local expected_title="$3"
  local expected_text="$4"

-  "${binary}" --outDir "${out_dir}" >/dev/null
+  run_launcher "${binary}" --outDir "${out_dir}" >/dev/null

  if [[ ! -f "${out_dir}/index.html" ]]; then
    echo "missing build output index.html for ${binary}" >&2
--- a/tests/script_test/run_script.sh
+++ b/tests/script_test/run_script.sh
@@ -3,7 +3,23 @@ set -euo pipefail

 binary="$1"
 expected="$2"
-output="$(${binary})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${binary}")"

 if [[ ${output} != "${expected}" ]]; then
  echo "Unexpected output from ${binary}: ${output}" >&2
--- a/tests/script_test/run_vite_app.sh
+++ b/tests/script_test/run_vite_app.sh
@@ -14,6 +14,23 @@ cleanup() {
 }
 trap cleanup EXIT

+start_launcher() {
+  local launcher="$1"
+  local log_target="$2"
+  shift 2
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" >"${log_target}" 2>&1 &
+  else
+    "${launcher}" "$@" >"${log_target}" 2>&1 &
+  fi
+  server_pid=$!
+}
+
 port="$(
  python3 - <<'PY'
 import socket
@@ -24,8 +41,7 @@ sock.close()
 PY
 )"

-"${binary}" --host 127.0.0.1 --port "${port}" --strictPort >"${log_file}" 2>&1 &
-server_pid=$!
+start_launcher "${binary}" "${log_file}" --host 127.0.0.1 --port "${port}" --strictPort

 for _ in {1..60}; do
  if ! kill -0 "${server_pid}" 2>/dev/null; then
--- a/tests/script_test/run_vite_monorepo_apps.sh
+++ b/tests/script_test/run_vite_monorepo_apps.sh
@@ -17,6 +17,23 @@ cleanup() {
 }
 trap cleanup EXIT

+start_launcher() {
+  local launcher="$1"
+  local log_target="$2"
+  shift 2
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" >"${log_target}" 2>&1 &
+  else
+    "${launcher}" "$@" >"${log_target}" 2>&1 &
+  fi
+  server_pid=$!
+}
+
 pick_port() {
  python3 - <<'PY'
 import socket
@@ -37,8 +54,7 @@ verify_vite_app() {
  port="$(pick_port)"
  log_file="${workdir}/${log_name}.log"

-  "${binary}" --host 127.0.0.1 --port "${port}" --strictPort >"${log_file}" 2>&1 &
-  server_pid=$!
+  start_launcher "${binary}" "${log_file}" --host 127.0.0.1 --port "${port}" --strictPort

  for _ in {1..60}; do
    if ! kill -0 "${server_pid}" 2>/dev/null; then
--- a/tests/script_test/run_workspace_parallel.sh
+++ b/tests/script_test/run_workspace_parallel.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 script_bin="$1"
-output="$(${script_bin})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${script_bin}")"

 if [[ ${output} != *"pkg-a"* ]]; then
  echo "Expected workspace parallel run output to include pkg-a: ${output}" >&2
--- a/tests/script_test/run_workspace_script.sh
+++ b/tests/script_test/run_workspace_script.sh
@@ -2,7 +2,23 @@
 set -euo pipefail

 script_bin="$1"
-output="$(${script_bin})"
+
+run_launcher() {
+  local launcher="$1"
+  shift
+  if [[ ${launcher} == *.cmd ]]; then
+    local command
+    printf -v command '"%s"' "${launcher}"
+    for arg in "$@"; do
+      printf -v command '%s "%s"' "${command}" "${arg}"
+    done
+    cmd.exe /c "${command}" | tr -d '\r'
+    return 0
+  fi
+  "${launcher}" "$@"
+}
+
+output="$(run_launcher "${script_bin}")"

 if [[ ${output} != *"pkg-a"* ]]; then
  echo "Expected workspace run output to include pkg-a: ${output}" >&2
--- a/tests/script_test/verify_launcher_flags.sh
+++ b/tests/script_test/verify_launcher_flags.sh
@@ -1,12 +1,21 @@
 #!/usr/bin/env bash
 set -euo pipefail

-binary="$1"
+launcher="$1"
 shift

-for expected in "$@"; do
-  if ! grep -Fq -- "${expected}" "${binary}"; then
-    echo "Expected ${binary} to contain ${expected}" >&2
-    exit 1
-  fi
-done
+python3 - "${launcher}" "$@" <<'PY'
+import json
+import pathlib
+import sys
+
+path = pathlib.Path(sys.argv[1])
+if path.suffix.lower() == ".cmd":
+    path = pathlib.Path(str(path)[:-4])
+spec = json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+argv = spec["argv"]
+
+for value in sys.argv[2:]:
+    if value not in argv:
+        raise SystemExit(f"missing {value!r} in argv {argv!r}")
+PY
--- a/tests/script_test/verify_monorepo_launcher_shape.sh
+++ b/tests/script_test/verify_monorepo_launcher_shape.sh
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+vite_launcher="$1"
+paraglide_launcher="$2"
+
+python3 - "${vite_launcher}" "${paraglide_launcher}" <<'PY'
+import json
+import pathlib
+import sys
+
+def read_spec(launcher: str):
+    path = pathlib.Path(launcher)
+    if path.suffix.lower() == ".cmd":
+        path = pathlib.Path(str(path)[:-4])
+    return json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+vite_spec = read_spec(sys.argv[1])
+paraglide_spec = read_spec(sys.argv[2])
+
+assert all(not root.startswith("../") for root in vite_spec["node_modules_roots"]), vite_spec
+assert "node_modules" in vite_spec["node_modules_roots"], vite_spec
+
+assert all(not root.startswith("../") for root in paraglide_spec["node_modules_roots"]), paraglide_spec
+assert "node_modules" in paraglide_spec["node_modules_roots"], paraglide_spec
+assert "packages/i18n/node_modules" in paraglide_spec["node_modules_roots"], paraglide_spec
+PY
--- a/tests/toolchain_test/BUILD.bazel
+++ b/tests/toolchain_test/BUILD.bazel
@@ -34,6 +34,7 @@ config_setting(

 sh_test(
    name = "bun_version_test",
+    size = "small",
    srcs = ["toolchain_version.sh"],
    args = select({
        ":linux_x86_64": ["$(location @bun_linux_x64//:bun)"],
@@ -53,6 +54,7 @@ sh_test(

 sh_test(
    name = "toolchain_resolution_matrix_test",
+    size = "small",
    srcs = ["toolchain_resolution_matrix.sh"],
    args = ["$(location //tests/toolchain_test:BUILD.bazel)"],
    data = ["//tests/toolchain_test:BUILD.bazel"],
Author	SHA1	Message	Date
eric	a58028d063	chore(release): v1.0.0 Some checks failed CI / test (ubuntu-latest, linux-x64) (push) Failing after 37s Details Docs Pages / deploy (push) Failing after 39s Details Copilot Setup Steps / copilot-setup-steps (push) Failing after 40s Details CI / test (macos-14, darwin-arm64) (push) Has been cancelled Details CI / test (windows-latest, windows) (push) Has been cancelled Details	2026-03-15 11:04:58 +01:00
eric	626a6640f8	feat: proper windows support	2026-03-15 11:04:44 +01:00