English · 简体中文
Zed editor extension for Basilisk — WASM-based Python type checking and language server integration.
Basilisk is an open-source Python type checker and language server built in Rust: diagnostics, autocomplete, refactoring, debugging, and profiling, with strictness configured per rule.
The type checker still contains code that isn't doing real type checking, and it is not yet trustworthy. Some rules decide from the way code is spelled rather than what it means, so they can be wrong in both directions — a false error on correct code, or silence where there is a genuine bug. Don't gate CI on it, and don't read a clean run as a clean codebase. Our former conformance claim and our benchmark figures are withdrawn, and Basilisk was removed from the official results at our request.
This was a mistake and a failure to verify — not an attempt to game the suite. Nothing was concealed from
python/typing; the submission ran the suite's own unmodified harness, and we published on a green run without ever checking whether our rules survived a semantics-preserving change. Basilisk's author has published a personal account and apology.We are auditing every rule and deleting the ones that don't hold up — not rewriting them, not patching them, with a failing test left behind so the gap stays visible. Where a rule can't be made reliable in a straightforward way, we will depend on a different, established type checker rather than ship our own unreliable version of it.
Basilisk is much more than a type checker. The language server, refactoring, formatting, debugging, and profiling don't rest on the rules under audit — those are what we are sharpening while it runs, removing anything that could hand you a misleading result. We are doing this to restore trust and turn Basilisk back into a tool you can believe. Read the correction.
Command palette (Cmd+Shift+P / Ctrl+Shift+P) → zed: install dev extension → select this directory (clone Nimblesite/basilisk-zed first if you do not have the monorepo). Zed compiles the extension to WASM itself — you never pre-build or copy a .wasm file.
You do not install the Basilisk binary separately. On first activation the extension downloads the matching binary for your platform from the GitHub release, caches it inside Zed's extension directory, and reuses it until a newer release appears. Override it only for development or a system install, via lsp.basilisk.binary.path in settings.json or the BASILISK_PATH environment variable.
The extension is not yet listed in the Zed extension registry; until that listing lands, the dev-extension flow above is the install path.
Full instructions, settings, debugging, and the slash-command reference: basilisk-python.dev/docs/install-zed.
This is the Zed editor integration. It is a native Zed extension compiled to WASM that connects the Basilisk language server to Zed, providing real-time diagnostics, hover, go-to-definition, code actions, and debugging via DAP.
- WASM extension — compiled as a
cdylibcrate targetingwasm32-wasip2, loaded natively by Zed. zed_extension_api— uses Zed's official extension API for language server lifecycle management.basilisk-common— shares diagnostic codes and constants with the rest of the Basilisk workspace (also WASM-compatible).- Built-in Python, untouched — binds to Zed's own Python language by name. The extension ships no
languages/directory and no grammar, so Zed compiles nothing from source and your highlighting, brackets, indent rules, and runnables stay exactly as Zed ships them. - DAP debugging — supports the Debug Adapter Protocol for integrated Python debugging.
From a monorepo checkout, build the extension and set up the local dev loop:
make package-zedStandalone (this repository on its own), the build is exactly the one the release pipeline gates the publish on:
cargo build --release --target wasm32-wasip2| Crate | Purpose |
|---|---|
zed_extension_api |
Zed extension API |
basilisk-common |
Shared constants and types |
MIT.