--- title: Chromium family and native Bun owners description: Reuse existing Python, system package, browser transport and toolchain owners for the Bun and JSC browser integration. --- # Chromium family and native Bun owners ## Read-only profile metadata — source contract, 2026-10-13 `bun:chromium.profiles.discover()` discovers Chrome/Chromium metadata on demand. An explicit `userDataDirs` list selects fixture or owner directories. `isDefault` means the literal `Default` directory; `isLastUsed` reflects `Local State`, which may select another profile. No profile is copied, unlocked or opened for writing. `profiles.readBookmarks(absoluteFile, { site, includeSubdomains })` reads one selected JSON file. Site filtering accepts HTTP(S), normalizes case and IDNA, and matches the exact hostname unless dot-delimited subdomains are requested. Metadata reads are bounded to 8 MiB; bookmark traversal is bounded to 100000 nodes and 64 folder levels. Errors do not include raw JSON values. `profiles.capabilities()` keeps encrypted-store export separate from APIs of an already connected browser. Direct cookies/password-store export is unavailable; site cookies and live tab metadata require their browser-native owners. Chromium Windows app-bound encryption validates the calling application as well as its user, according to `chrome/browser/os_crypt/README.md`; DPAPI alone does not establish access to those values. Branded Chrome also rejects remote-debugging switches with its normal user-data directory. Discovery does not change either policy or launch a browser against that directory. CEF/WebView2 persistence remains in the destination engine's own store. The corresponding tests use synthetic `Local State` and `Bookmarks` files. Source contracts do not establish qualification of a live protected profile or native Windows credential handling. Owner directive, 2026-10-11: support Chromium-family browsers across qualified platforms and converge browser JavaScript on Bun's JavaScriptCore. Reuse native Bun owners for Python, dependencies, toolchains and browser lifecycle. The delivery product remains one Bun CLI, runtime, FFI, MCP registry and agent plugin. This inventory describes actual source and installed help, not a qualified Chromium build or replacement of Chromium's V8 internals. ## Existing owners to reuse | Capability | Source owner | Reuse and qualification boundary | | --------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Embedded UV, Python project/interpreter acquisition | `vendor/uv`, `scripts/aphrody/buv.ts`, `packages/buv` | `bun uv` dispatch already exists. Preserve UV resolution, lock, caches, interpreter selection and child exit codes. Artifact receipts identify UV/Bun/JSC/CPython pins. | | Python command dispatch | `src/runtime/cli/python_command.rs` | Python source/CLI uses the lazy ABI-versioned host; no second command parser. Keep argv, Unicode paths, environment, cwd, exit status and subprocess behavior. | | In-process Python API | `src/js/bun/python.ts`, `packages/bun-python-native/crates/bun-python-host` | `bun:python` reuses the host through Bun FFI. Host ABI 1 and explicit CPython library selection precede execution. A successful embedded evaluator is not depot_tools CLI parity. | | Python build/conformance | `src/runtime/cli/python_compile.rs`, `packages/bun-python-conformance`, `packages/bun-python-toolchain` | Reuse target/host provenance, codec/CLI conformance and compiler owner. Do not install a parallel Python launcher to hide a missing native contract. | | System dependency resolution/install | `src/install/system`, `packages/aphrody-pkg-system`, `src/install/PackageManager/install_with_manager.rs` | `systemDependencies` feeds the existing lock/install owner; APK, winget and the Linux Debian/APT adapter are implemented in source. Candidate native APT CLI execution remains unqualified; pacman is unsupported. | | Factory/bootstrap dependency setup | `scripts/aphrody/setup.ts`, `scripts/aphrody/deps.json` | Existing dry-run/dependency inventory and platform bootstrap can use apt-get/apk/brew/winget explicitly. This is not proof that `bun pm apt` exists. Execute approved host changes through Infra; no global workstation install. | | Windows native toolchain | `bun msvc`, `scripts/build/tools.ts` | Existing discovery resolves MSVC/SDK/LLVM/CMake/Ninja. Reuse its explicit setup plan and exec environment rather than manually modifying PATH or registry. | | Browser detection/lifecycle/CDP pipe | `src/runtime/webview/ChromeProcess.rs`, `ChromeBackend.cpp`, `JSWebViewConstructor.cpp` | Native Bun.WebView owner finds Chrome/Chromium/Brave/Edge and manages pipe lifecycle. Respect explicit backend path and isolation; a CDP connection to Chromium still executes Chromium's current V8. | | Platform WebView transport | `src/runtime/webview/HostProcess.rs`, `WebKitBackend.cpp`, `packages/bun-webview-core` | Existing macOS WKWebView and optional host source use platform engines. The package has a historical `bun-webview-host` helper; it is not an authorization to create another product or claim all backends qualified. | | CEF acquisition/bundling | `bun-os/packages/bun-tauri/crates/aphrody-tauri-cli/src/runtime/cef.rs`, `aphrody-tauri-runtime-cef`, `aphrody-tauri-bundler` | Existing owner resolves CEF version/target/cache and bundles resources. CEF is a desktop boundary; do not make it a competing crawler or claim its V8 was replaced. | | Browser SDK/automation | `packages/bun-webview-page`, `packages/bun-web`, `src/browser` | Reuse existing Bun.WebView CDP adapter and imported DOM/layout/network/automation. The page adapter explicitly documents simplified accessibility, first-match locators and viewport screenshots. Keep corresponding parity work open. | ## Live help inspected without installation The installed workstation runtime reports `1.4.3-aphrody.4+41211b568`. Its help was read on 2026-10-11; this runtime is distinct from the unbuilt 1.4.4 manifests and candidate source. - `bun --help` advertises native `uv`, `install`, `msvc`, `ssh`, `mcp` and `agent-plugin` commands. It does not prove candidate engine behavior. - `bun uv --help` exposes `run`, `sync`, `python`, `pip`, `venv`, `build` and `tool`; `--no-python-downloads` permits inspection without acquisition. - `bun install --help` exposes frozen lockfile and lifecycle-script controls. Source and `docs/pm/winget.mdx` establish the system-dependency contract. - `bun msvc --help` exposes `doctor`, `info`, `which`, `env`, `exec` and `setup --dry-run`. Reading help does not run setup or edit configuration. No build, test, package install, toolchain setup or global configuration change was performed to create this inventory. ## System packages: implemented and missing `src/install/system/mod.rs::source_for` returns APK, winget and `deb::apt::Deb` providers. `cli.rs::run` dispatches `apt` and `deb` to the existing Debian owner. Pacman still has no provider and returns an explicit unsupported error. Candidate native CLI execution requires its own receipt. Winget resolves its index/manifests directly, validates hashes, selects the host installer and refuses unsupported elevation. APK owns repository/rootfs transactions and script policy. Retain those owners and exact lock provenance. The Linux adapter in `src/install/system/deb/apt.rs` delegates signature checks, dependency solving and transactions to existing APT/dpkg executables. It keeps authentication checks enabled, records exact package metadata and requires an explicit initialized Debian root for transactions. Its separate `apt plan` command handles local metadata only and does not verify Release signatures. Qualify candidate CLI dispatch, root isolation, offline/elevation behavior and real signed-repository transactions before declaring delivery. Factory bootstrap may use its declared apt-get path and must report that execution explicitly. ## Python and depot_tools compatibility Reuse embedded UV for interpreter/project acquisition and Bun's CPython host for Python execution only where its native contract matches the invoked tool. depot_tools and Chromium tooling can inspect `sys.executable`, launch child Python interpreters and depend on filesystem/environment/exit semantics. An in-process `Python.eval` call does not replace those executable contracts. Preserve `BUN_PYTHON_HOST_LIBRARY`, `BUN_PYTHON_LIBPYTHON`, explicit `BUN_PYTHON_EXECUTABLE`/virtual-environment selection, host ABI and interpreter revision. Keep protected auth/caches outside source. The dedicated toolchain integration lot owns depot_tools pins and qualification; this document creates no alternate launcher, global install or substitute dependency manager. ## Chromium and JSC are separate qualification decisions The current native detection order is explicit `backend.path`, `BUN_CHROME_PATH`, PATH, platform application locations and historical browser caches. `BUN_WEBVIEW_HOST` selects the existing optional platform host. Browser reuse is process-owned; independently isolated profiles/contexts require qualification, not inference from multiple JavaScript wrapper instances. Retain Chromium-family acquisition/CDP compatibility while implementing a separate remote-page realm in Bun JSC. The realm must not expose Bun, Node, Python, FFI, filesystem, process, environment or system installers to remote content. Qualify DOM/GC handles, modules, promises/microtasks, timers, workers, interrupts, exceptions and teardown with identical fixtures before retiring the legacy page V8 provider. Supporting CDP clients is not replacement of Chromium or CEF's internal JavaScript engine. A Chromium-internals JSC replacement needs its own explicit embedding, build and behavior proof. The feature inventory hashes `ChromeProcess.rs` and the page JavaScript build script alongside workspace manifests. The page build's cross-target snapshot path now rejects a missing target `cross-mksnapshot` instead of embedding a host architecture snapshot. Cross-target execution still requires a matching snapshot producer and actual target fixture receipt before packaging or activation. The native Bun/JSC candidate and existing Chromium CDP process require their own source-matched runtime receipts. ## Execution and dependency order All compilation, tests, Clippy and benchmarks run on the allocated SSH VPS factory. The latest requested disk envelope is 108 GB; prior browser receipts recorded a 107 GiB allocation and 45 GiB RAM. These reported units are not interchangeable. Record current free bytes, memory, source/artifact sizes, resource lease and target before source sync, dependency acquisition or build. The current factory root is `/home/ubuntu/builds/bun-os-factory`. 1. Inspect source/toolchain pins and native owner help, then plan dependency acquisition without applying global workstation changes. 2. Qualify host Python/depot_tools execution, toolchain and package dependency closure on the VPS, including the candidate native APT adapter. 3. Build the Bun candidate and qualify native HTML/CSS/JSC browser bindings. 4. Run real Chromium-family CDP fixtures and remote-page JSC parity separately, then Linux/Windows/macOS target/build/installation gates. 5. Record artifact/checksum/host/target/fixture pins, failures and skips; measure comparable performance and switch consumers only after stability. The actionable queue is [TODO-BUN](../../TODO-BUN.md). Existing compatibility paths remain until their replacements are qualified; no new independent browser executable, FFI server, MCP server or plugin is a delivery step.