OSS-first docs
These docs teach the open system first: contracts, generated surfaces, runtimes, governance, and incremental adoption. Studio shows up as the operating layer on top, not as the source of truth.
Contract-first API
Design APIs by writing contracts first, then generate consistent implementations across frameworks.
Problems Solved
- API drift between frontend and backend
- Inconsistent error handling across endpoints
- Documentation becomes outdated quickly
- Manual OpenAPI maintenance is error-prone
Solutions
- Single source of truth for API contracts
- Generate OpenAPI and SDKs from contracts
- Type-safe request/response validation
- Always-in-sync documentation
Quick Start
Define your first API contract and generate consistent implementations.
src/contracts/user-create.operation.ts
import { defineOperation } from '@contractspec/lib.contracts-spec/operations';
import { SchemaModel, ScalarTypeEnum } from '@contractspec/lib.schema';
export const CreateUserOperation = defineOperation({
goal: 'Create a new user account with validation',
context: 'Used by frontend registration forms and internal admin tools',
input: new SchemaModel({
type: 'object',
properties: {
email: {
type: 'string',
format: 'email',
required: true,
},
password: {
type: 'string',
minLength: 8,
required: true,
},
},
}),
output: new SchemaModel({
type: 'object',
properties: {
id: { type: 'string', required: true },
email: { type: 'string', required: true },
createdAt: { type: 'string', format: 'date-time', required: true },
},
}),
metadata: {
name: 'createUser',
tags: ['users', 'auth'],
description: 'Create a new user account with email and password',
},
});Generate OpenAPI
Export OpenAPI documentation directly from your contracts.
export-openapi
contractspec openapi export \
--registry ./src/contracts/registry.ts \
--out ./openapi.jsonOSS docsStart with OSS. Adopt Studio when you want the operating layer.
Why ContractSpec
Keep educational and comparison content reachable without letting it define the primary OSS learning path.