AGENTS.md

1# Petrinaut
2 
3Visual editor for Stochastic Dynamic Colored Petri Nets (SDCPN). Published npm package (`@hashintel/petrinaut`).
4 
5## Stack
6 
7- React 19 with React Compiler (babel-plugin-react-compiler)
8- TypeScript (type-checked with `tsgo`)
9- Vite 8 + Rolldown (library build + demo site)
10- Panda CSS for styling
11- oxlint for linting
12- vitest for testing
13 
14## React Compiler
15 
16React Compiler is enabled — it automatically memoizes components and hooks.
17 
18**Do not use `useMemo`, `useCallback`, or `React.memo` unless there is a specific reason the compiler cannot handle it.** The compiler makes manual memoization unnecessary in the vast majority of cases.
19 
20When code is genuinely incompatible (e.g. writing to refs during render), opt out with:
21 
22```ts
23function useMyHook() {
24  "use no memo"; // <reason why>
25  // ...
26}
27```
28 
29The compiler runs with `panicThreshold: "critical_errors"` — the build fails if it encounters critical errors not opted out via `"use no memo"`.
30 
31## Commands
32 
33```sh
34yarn dev              # Dev server (demo site)
35yarn build            # Library build
36yarn lint:eslint      # Lint with oxlint
37yarn lint:tsc         # Type check with tsgo
38yarn test:unit        # Unit tests (vitest)
39```
40 
41## Conventions
42 
43- Function components only (no class components except error boundaries)
44- `use()` for context consumption (React 19), not `useContext()`
45- Styles via Panda CSS (`css()`, `cva()` from `@hashintel/ds-helpers/css`)
46- No `@local/*` imports — this is a published package
47- Prefix unused parameters with `_`
48