riz: Instructions file for Claude Code

CLAUDE.md

riz is a self-hosted AWS Lambda + API Gateway v2 runtime in one Rust binary: six runtimes (Bun, Node.js, Python, Rust, Go, WASM), every function an MCP tool, no per-request cold start. Scope is HTTP/WS Lambdas only — SQS/SNS/S3/ EventBridge-style event sources are out of scope by decision, not omission.

Safety-critical rules (binding)

docs/SAFETY.md — NASA's Power of 10 adapted to Rust — is binding for all code compiled into the riz binary (src/, i.e. --lib --bins). Examples (examples/lambdas/*), tests, benches, and fixtures are exempt by policy.

Working rules that follow from it:

• The enforced lint tier lives in Cargo.toml [workspace.lints] (+ clippy.toml thresholds); only the riz package opts in.
• scripts/safety-check.sh --gate is a CI gate (prod-only zero-tolerance lints, e.g. clippy::panic).
• scripts/safety-check.sh prints the ratchet report — violation counts may only go down. Never add a site to a ratchet lint; when a lint's count hits zero, promote it (ratchet → gate → enforced) per the protocol in docs/SAFETY.md.
• Every unsafe block needs #[allow(unsafe_code)] at the site plus a // SAFETY: proof, one operation per block. Any other #[allow] of a safety lint needs an adjacent justification comment.
• New code in src/: no unwrap/expect/panic!/indexing-[] on runtime data, bounded channels only, loops either provably bounded or matching the supervised event-loop contract (docs/SAFETY.md rule 2).

Build & test gates

Run before every push (CI enforces all of them):

cargo fmt --all -- --check
cargo clippy --workspace --all-targets -- -D warnings
./scripts/safety-check.sh --gate
cargo nextest run --workspace -E 'not binary(e2e_smoke_all) and not binary(template_smoke_all) and not binary(perf_regression) and not binary(chaos) and not binary(aws_conformance)'
cargo nextest run --test e2e_smoke_all   # isolated: boots the example fleet
cargo nextest run --test template_smoke_all  # isolated: scaffolds + boots all six templates
cargo nextest run --test perf_regression --no-capture  # isolated: throughput/latency floor + trend
cargo nextest run --test chaos               # isolated: deliberate fault injection
cargo nextest run --test aws_conformance     # isolated: clones + boots AWS's own Lambda samples (skips offline)
# or the whole flow in one command: scripts/validate.sh