Development

This page is for contributors to function-wasm. It lists the commands that build, test and lint a change, and says which of them CI runs for you. It assumes a checkout with a Rust toolchain.

Commands that run on every push

CI runs these on every push, and on a pull request that changes code (a pull request touching only Markdown, JSON or SVG files skips them):

cargo build --workspace && cargo test --workspace
cargo fmt --all --check && cargo clippy --workspace --all-targets --all-features -- -D warnings
cargo deny check advisories bans licenses sources   # cargo install cargo-deny --locked

The tests include the conformance goldens and the scaffold goldens. The cargo deny run checks Cargo.lock against deny.toml: every crate is free of published advisories, under an allowed license and from crates.io. A pull request that touches the documentation (docs/, README.md, SECURITY.md or book.toml) also runs Vale:

make vale

Commands that run on demand

These need Go, Docker or kind on your machine:

(cd examples/pdb-addon && go test ./...)
make -C examples/pdb-addon render
make e2e

The first line tests the Go example and its vendored internal/wasmfn glue. The second is the development loop. The third runs the end-to-end suite in a kind cluster. Testing explains the two tiers and the /e2e comment that runs them on a pull request.

Guest toolchains

The workspace tests build every scaffold (what guestfn init writes) to WebAssembly and run each through the host. The tests skip a scaffold whose toolchain isn’t on PATH, so an all-green run can mean a guest never ran. The toolchains are go, cargo and rustup for the rust scaffold’s pinned toolchain (which also needs protoc), zig, npm and python3. Set FUNCTION_WASM_REQUIRE_TOOLCHAINS=1 to make a missing toolchain a failure.

Where to go next

Testing says where a new test goes. AGENTS.md describes the source layout and conventions. Design records lists the design documents.