typia: Ultra-Fast Runtime Validators and Serializers via TypeScript Transformation
Leverage TypeScript type transformation to generate zero-dependency, super-fast runtime validators, JSON serializers, LLM function calling harnesses, and Protocol Buffer codecs.
- Source repo
- samchon/typia
- Stars
- ★ 5.9k
- Last updated
- 4d ago
- License
- MIT
- Primary language
- TypeScript
- FA score
- 42/100 · Major gaps
At a glance
- How it runs
- Works with
- Universal · cross-platform
- Cost
- Free, no paid service needed
- Setup effort
- Medium · a few setup steps
- You'll need
- Typical use
- TypeScript developers seeking zero-dependency runtime data validation to replace class-validator and similar libraries, with higher performance.
- Not a fit if
- Projects locked to stock tsc, ts-node or tsx; typia requires the ttsc toolchain
- Teams unwilling to add compile-time transforms and bundler plugin config
- Codebases relying on advanced TypeScript type constructs typia may not support
- Source review
- 42/100 · Major gaps 8 safety controls not found
What does this agent do, and when should you use it?
typia is a transformer library for TypeScript that generates efficient runtime validators, serializers, and parsers directly from TypeScript types at compile time. It offers validation functions like is, assert, and validate; a json namespace for JSON Schema and serialization/parsing; an llm namespace for function calling applications and structured outputs; a protobuf namespace for Protocol Buffer message encoding/decoding; and a random function for generating random data. typia claims its runtime validators are 20,000x faster than class-validator and JSON serialization 200x faster than class-transformer. Developers write plain TypeScript types, and typia generates corresponding runtime code at build time, eliminating the need for additional schemas or runtime reflection.
typia analyzes TypeScript types during compilation and transforms calls like typia.is<T>() into dedicated type-checking code. It reads TypeScript source files, applies transformation via ttsc (a TypeScript compiler wrapper), and outputs optimized JavaScript runtime functions. Specific features include: is<T>() returns a boolean, assert<T>() throws TypeGuardError, validate<T>() returns detailed validation results; json.schema<T>() generates JSON Schema, json.assertParse<T>() and json.assertStringify<T>() provide type-safe parsing and serialization; llm.application<Class>() generates a collection of function calling schemas and validators, llm.structuredOutput<P>() generates structured output schemas, llm.parse<T>() performs lenient JSON parsing; protobuf.message<T>() generates Protocol Buffer message definitions, protobuf.assertDecode<T>() and protobuf.assertEncode<T>() perform safe decoding/encoding; and random<T>() generates random data. The workflow is: install typia and ttsc, build with ttsc, call typia functions in code, and the transformation happens automatically.
- TypeScript developers seeking zero-dependency runtime data validation to replace class-validator and similar libraries, with higher performance.
- Generating JSON Schema automatically from TypeScript types for API documentation or validation.
- Building LLM function calling applications that require accurate function parameter schemas and result parsing.
- Using Protocol Buffer for efficient data encoding/decoding while maintaining type safety.
- Generating random test data that conforms to TypeScript types during development and testing.
- Eliminating the need to manually maintain separate schemas and type definitions by using a single type source to drive all runtime needs.
How do you install or deploy this agent?
Install typia with the ttsc toolchain:
npm i typia
npm i -D ttsc typescriptNote: You must use ttsc instead of tsc, as ttsc applies typia's transform. For bundler integration (Vite, Next.js, etc.), install @ttsc/unplugin.
How do you use this agent?
In a TypeScript file, import typia and use its functions, e.g., import typia from "typia"; const checkString = typia.createIs<string>();. Then build with ttsc: npx ttsc, or run a script directly: npx ttsx src/index.ts. typia generates the corresponding validator code at build time.
What are this agent's strengths and limitations?
- Extreme performance: runtime validation is 20,000x faster than class-validator and JSON serialization is 200x faster than class-transformer (per README).
- Pure TypeScript type-driven: no extra schemas or decorators, reducing maintenance overhead.
- Comprehensive features: validation, JSON, LLM function calling, Protocol Buffer, and random data generation.
- Type safety guaranteed by compile-time transformation, reducing runtime errors.
- Requires the ttsc toolchain; standard tsc or ts-node do not work, adding build configuration complexity.
- Integrating with some bundlers requires additional plugins (e.g., @ttsc/unplugin), which may cause compatibility issues.
- Compile-time transformation may increase build time, especially for large projects.
- Not all TypeScript types may be supported, requiring workarounds for advanced type constructs.
How does this agent compare with similar options?
Similar to typescript-is, but typia offers a broader feature set (JSON, LLM, protobuf) and better performance. Other libraries like class-validator require decorators and schemas, with lower performance.
Key facts side by side with the most closely related agents.
| Agent | Source review | Form / cost | Stars | Updated | Language | Full support on |
|---|---|---|---|---|---|---|
| typia: Ultra-Fast Runtime Validators and Serializers via TypeScript Transformation This agent | 42 · Major gaps | Library / SDKFree | ★ 5.9k | 4d ago | TypeScript | — |
| TanStack AI | 76 · Some gaps | Library / SDKFree + model costs | ★ 3.2k | 4d ago | TypeScript | OpenAI API · Claude API |
| Langroid | 70 · Some gaps | Library / SDKFree + model costs | ★ 4.1k | today | Python | Claude Code · OpenAI API |
| Adaline Gateway | 69 · Some gaps | Library / SDKFree + model costs | ★ 607 | 2mo ago | TypeScript | OpenAI API · Claude API |
How does FollowAgents rate this agent?
Why each dimension lost points
Evidence shows an open-source library with no mechanisms for least privilege, user confirmation, data flow transparency, sensitive data handling, external effects, rollback, or source attribution. Dependency security: package.json lists devDependencies but no lock or security audit. Thus all trust criteria score 0.
Self-consistency: README and package.json align, feature list clear, score 2. Dependency availability: dependencies managed via pnpm with lock file, but availability not verified, score 2. Failure messages: error handling exists but no detailed failure message documentation, score 1.
Audience and scenarios: README lists multiple use cases (validation, JSON, LLM, protobuf), score 2. Capability boundaries: features documented but boundaries not explicit, score 2. Trigger precision: API design clear, score 2. Environment fit: supports multiple bundlers but requires specific toolchain, score 2.
Information architecture: clear documentation structure with guides and API docs, score 2. Install notes: installation steps provided but dependent on specific tools, score 2. Naming stability: consistent API naming, score 2. Examples and FAQ: examples present, FAQ missing, score 2. Known limitations: not explicitly listed, score 1. License: MIT license clear, score 2. Versioning and changelog: version number present, no changelog, score 1. Maintenance responsibility: author and repository present, score 2.
Output usability: outputs are type-safe validators and serializers, score 2. Marginal value: provides unique features, score 2. Cost benefit: performance claims have benchmarks but not verified, score 2.
Claim traceability: performance claims have benchmark links but not verified, score 1. Cross-source corroboration: community use cases exist but not independently verified, score 1. Fact-inference separation: documentation distinguishes facts and inferences but not clearly, score 1.
- Not found in source: least-privilege scopingGrant only what the task needs: a dedicated account or read-only token, scoped to specific directories and repos.
- Not found in source: confirmation before actingTurn on (or add) a confirmation step before it acts, and try it in a sandbox or test environment before real data.
- Not found in source: data-flow disclosureWatch which external services it contacts (proxy or firewall logs) and keep sensitive data out until you know where it goes.
- Not found in source: sensitive-data handlingUse dedicated, low-privilege, revocable API keys — never production credentials — and keep secrets out of logs.
- Not found in source: dependency securityPin versions and run a dependency audit (npm audit, pip-audit) before installing; prefer running it in a container.
- Not found in source: disclosed external effectsEstablish which external systems it writes to, sends to or changes, and verify with test accounts or repos before production.
- Not found in source: rollback or recovery pathBack up first, or work on a git branch or snapshot, so its changes can be undone.
- Not found in source: verifiable attributionInstall from the official repo or registry and check the publisher and URL to avoid look-alike packages.
- This is a static review; code not executed, performance claims unverified.
- Dependency security not audited; recommend checking for vulnerabilities.
- Requires specific toolchain (ttsc), may limit environment fit.
Recent releases
Latest entries from the project's GitHub Releases. Notes are quoted from upstream as written, not rewritten or tested by FollowAgents.
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Release notes excerpt
🚀 Features - contracts: - Enforce implementation and test acknowledgments - by @samchon and Claude Sonnet 5.5 in https://github.com/samchon/typia/issues/2472 [<samp>(1d4ba)</samp>](https://github.com/samchon/typia/commit/1d4ba38d8e) - llm: - ILlmEvaluation.IConfig decimals replaces decode rounding - by @samchon in https://github.com/samchon/typia/issues/2469 [<samp>(3d877)</samp>](https://github.com/samchon/typia/commit/3d8770fd91) …View on GitHub ↗ -
Release notes excerpt
🐞 Bug Fixes - HTTP decoder contracts, HttpMigration path-derived names, non-finite numbers, and Swagger 2.0 parameter round trip - by @samchon and Claude Opus 5.5 (1M context) in https://github.com/samchon/typia/issues/2453 [<samp>(d9263)</samp>](https://github.com/samchon/typia/commit/d9263e202f) …View on GitHub ↗ -
Release notes excerpt
🚀 Features - @typia/jev, Jev wire format with TypeSafe and OpenRouter evaluation helpers - by @samchon and Claude Fable 5.1 in https://github.com/samchon/typia/issues/2410 [<samp>(cbf5d)</samp>](https://github.com/samchon/typia/commit/cbf5dba8db) - jev: Make evaluation release-ready - by @samchon [<samp>(29a14)</samp>](https://github.com/samchon/typia/commit/29a1445f29) …View on GitHub ↗