A generic, type-safe store implementation using subscribe/setState pattern with React hooks integration via useSyncExternalStore. Provides createStore<T>(initialState) returning { getState, setState, subscribe, useStore } and createSignal<Args>() for event-only signals. The store is framework-agnostic and can be extracted into any TypeScript project needing lightweight reactive state management without external dependencies.

A synchronous state machine for managing query lifecycle with three states (idle, dispatching, running). Compatible with useSyncExternalStore for React integration. Provides guard methods (canDispatch, canRun, isRunning) and transition methods (dispatch, run, finish, cancel). The pattern is reusable for any async operation that needs to prevent concurrent execution and expose state to UI components.

An iterative Unicode sanitization utility that removes hidden/dangerous characters (zero-width spaces, control characters, bidirectional overrides, homoglyph attacks) using NFKC normalization and explicit range removal. Handles edge cases like null bytes, replacement characters, and partial surrogate pairs. The algorithm is self-contained and can be extracted into any project needing input sanitization against Unicode-based injection attacks.

A structured permission rule matching engine supporting exact, prefix, and wildcard patterns with proper escape handling. Used by the shell permission system to match commands against allow/deny rules. The matching logic is isolated, well-tested, and can be reused in any application needing hierarchical pattern matching with escape sequences.

A cross-process lock implementation using O_EXCL atomic file creation with PID liveness probes and stale recovery. Handles edge cases like PID reuse windows (documented race condition), cleanup on process exit, and session-based ownership. The pattern is reusable for any Node.js application needing distributed locking without external dependencies.