x-to-zodJSON Schema to Zod

Enhanced fork of json-schema-to-zod — converts JSON Schema draft-2020-12 into Zod schemas using a fluent builder pattern, with full Zod v3/v4 dual-mode support.

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Fluent builder architecture

Complete rewrite of internal code generation using fluent builders. Consistent lazy evaluation and smart constraint merging across every schema type.

Zod v3/v4 dual-mode

Generate schemas compatible with either Zod v3 or v4 via the zodVersion option. v4 mode emits z.strictObject(), z.looseObject(), and .extend().

Enhanced Zod v4 coverage

Full support for v4 types — void, date, bigint, symbol, nan, set, map, promise, lazy, codec, pipe, json, file, nativeEnum, templateLiteral, xor, keyof, and the full string-format validator matrix.

Post-processing system

Transform Zod builders after parsing with custom post-processors. Type-based and path-based filtering for organization-wide rules.

Type-safe builder params

All Zod v4 factory functions accept properly typed params — full IntelliSense for error options, constraints, and every Zod param.

Modern tooling

Vitest for tests, oxlint for linting, ESM build with moduleResolution "bundler" for compatibility with modern bundlers.