valcheckerRuntime-first validation with zero guesswork

Modular TypeScript validation library with composable steps, full type inference, and deterministic issue reporting.

Composable Step Pipeline

Chain built-in validation steps or create custom plugins. Each step can validate, transform, or handle failures—all with the same ergonomic API.

Schemas stay synchronized with TypeScript types through transforms, narrowing checks, and fallback chains. No manual type assertions needed.

Every validation failure produces structured issues with codes, payloads, and deep paths—perfect for form validation or API error responses.

Import all steps with `allSteps` for rapid prototyping, or cherry-pick only what you need for production bundles that stay lean.

Mix synchronous and asynchronous steps freely. Database checks, API calls, and pure validation all flow through the same deterministic pipeline.

Trim strings, parse JSON, filter arrays, and normalize data inline—no need to scatter preprocessing logic across your codebase.