Best Practices

The plugin ships a library of React Native best-practice rules that are checked automatically during Phase 4 (Architecture) and Phase 6 (Code Review) of /rn-feature-dev. Most rules are integrated from Vercel’s agent-skills (composition patterns, list performance, animations, state management) — see that repository for the full rule text. The rules live inside the plugin package and need no setup.

Impact levels

Level	Meaning	When checked
CRITICAL	Can cause crashes or data loss	Always checked
HIGH	Significant performance or UX impact	Always checked
MEDIUM	Noticeable improvement	Checked when relevant patterns present
LOW	Minor optimization	Checked on 3+ occurrences

Custom rules

Four rules were written for this plugin (not part of the Vercel set), covering failure modes discovered while verifying features on device:

Rule	Covers
navigation-transparent-modal	Transparent modal screens that break navigation introspection
query-cache-reactive	React Query cache reads that silently go stale
reanimated-in-lists	Reanimated shared values inside virtualized list items
theme-memoization-lists	Theme-object identity churn re-rendering whole lists

How rules are applied

During architecture design the agent filters rules by trigger keywords and file globs, then checks the CRITICAL and HIGH rules against the proposed design. During code review the same filter runs against the diff. Findings cite the rule id so you can look up the reasoning.