Schema validation

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• v8rA command-line JSON, YAML and TOML validator that's on your wavelength
• skemataAn object structure and type validation library
• 12factor-envEnvironment variable validation for 12-factor apps
• hemera-ajvThis is a plugin to use Ajv (JSON-Schema) for request validation.
• livrLightweight validator supporting Language Independent Validation Rules Specification
• @amritk/mjstGenerate TypeScript parsers and type definitions from JSON Schemas.
• personnummer.jsJavaScript script to validate and parse Swedish personal identity numbers and corporate identity numbers. Written in TypeScript and includes types.
• nimn_schema_builderBuild schema from JS object or JSON to feed into nimnjs
• @amritk/runtime-validatorsExtremely fast, eval-free runtime JSON Schema validation. Interprets a schema you do not know ahead of time — no new Function, no build step, runs anywhere.
• @evomap/gep-sdkSingle source of truth for the Genome Evolution Protocol (GEP): JSON Schemas, specification, and protocol-level helpers (canonicalize / computeAssetId / verifyAssetId).
• json-schema-instantiatorA simple instantiator for json schemas.
• check-linksRobustly checks an array of URLs for liveness.
• bankdata-germanyData and BIC Validator for German Banks
• json-schema-testTesting JSON schemas against sample data
• is-valid-abnCheck if a number is a valid Australian Business Number (ABN)
• aontuJSON-superset unification language and validation gate for AI-agent ground truth - evaluate, vet, diff, query, and evolution-check structured models.
• @amritk/apiFramework-agnostic, contract-first API layer built on mjst JSON Schema tooling. Typed routes, fast request/response validation, and OpenAPI 3.2 generation with no extra code — adapters for fetch (Hono, Next.js, Bun, Workers) and Node (Express, Fastify).
• attio-ts-sdkType-safe TypeScript SDK for the Attio CRM API with Zod v4 runtime validation
• german-tax-id-validatorSimple package to validate a german tax ID (Steuerindentifikationsnummer)
• container-validatorCargo container validator ISO 6346 implemented in Javascript
• @techery/zod-to-vertex-schemaConvert Zod schemas to Vertex AI/Gemini compatible schemas
• interface-forgeA TypeScript library for creating strongly typed mock data factories using Faker.js for test data generation
• zod-search-paramsZod utility for parsing search params
• @nesto-software/json-schema-ref-parserParse, Resolve, and Dereference JSON Schema $ref pointers
• document-modelPowerhouse document model — foundational data structure for local-first, event-sourced documents with typed operations, reducers, and GraphQL schema validation.
• zodownWrite Zod v4 schemas, run them in Zod v3 environments
• shapeAn object shape validation utility.
• validate.io-boolean-primitiveValidates if a value is a boolean primitive.
• io-ts-to-json-schemaUnderstandable io-ts error reports.
• @bahmutov/is-my-json-validA JSONSchema validator that uses code generation to be extremely fast
• luhn-validationA full TypeScript EAN, UPC, IMEI, EID, ISBN & card validation tool
• @pyramation/json-schema-to-typescriptcompile json schema to typescript typings
• validate-polishUtility library for validation of PESEL, NIP, REGON, identity card etc. Aimed mostly at Polish environment. [Polish] Walidacja numerów pesel, nip, regon, dowodu osobistego.
• @wotnak/json-render-coreJSON becomes real things. Define your catalog, register your components, let AI generate.
• @pyramation/json-schema-ref-parserParse, Resolve, and Dereference JSON Schema $ref pointers
• @anttiviljami/json-schema-ref-parserParse, Resolve, and Dereference JSON Schema $ref pointers
• types-joiTypeScript definitions for joi (Object schema description language and validator for JavaScript objects) https://joi.dev/
• node-ratifyA rich and efficient node validation library for String, Number, Date and Javascript Objects
• google-play-billing-validatorServer side for (Node.js) solution to validate Google Play Purchases and Subscriptions
• zodvexCodec-first Zod v4 integration for Convex -- type-safe validation, encoding, DB wrapping, and codegen.
• koa-better-error-handlerA better error-handler for Lad and Koa. Makes `ctx.throw` awesome (best used with koa-404-handler)
• rm-json-schema-to-typescriptcompile json schema to typescript typings. Fork from original json-schema-to-typescript with changed reference resolving. Will be deprecated when original repo accepts changes
• @gqloom/coreCreate GraphQL schema and resolvers with TypeScript.
• api-checkValidate the api to your functions to help people use them correctly. This is pretty much React's propTypes without React.
• optionerProcess and validate options for your module.
• @objectstack/lintStatic, build-time validation for an ObjectStack metadata graph — dashboard widget bindings, CEL/predicate expressions, and more. Pure (stack) => Issue[] functions shared by the CLI's `os validate` and any other consumer (e.g. AI authoring). Depends on @o
• @miyauci/isxCollection of validation functions for JavaScript data
• mongoose-validatorValidators for mongoose models utilising validator.js
• image-validatorA small and simple utility package that can validate any kind of image. It can detect corrupt files, or invalid image urls
• create-validator-tsCreate JSON Schema validator from TypeScript.

• valibot vs zod
• @asteasolutions/zod-to-openapi vs zod-openapi
• @hey-api/openapi-ts vs zod-openapi
• @hey-api/openapi-ts vs @asteasolutions/zod-to-openapi
• convict vs envalid
• type-graphql vs quicktype-core
• io-ts vs runtypes
• json-schema-to-typescript vs ts-json-schema-generator
• valibot vs superstruct
• @standard-schema/spec vs json-schema-to-ts
• @standard-schema/spec vs runtypes
• typebox vs ts-json-schema-generator
• @standard-schema/spec vs io-ts
• superstruct vs express-validator
• @apidevtools/swagger-parser vs @zodios/core
• json-schema-to-ts vs runtypes
• effect vs json-schema-to-ts
• graphql-scalars vs graphql-query-complexity
• joi vs v8n
• json-schema-to-ts vs io-ts