tygor

Type-safe Go backend for web apps.

Write Go functions, call them from TypeScript with full type safety. No IDL required.

What it looks like

Write Go types and handlers:

type User struct {
	ID    int64  `json:"id"`
	Name  string `json:"name"`
	Email string `json:"email" validate:"required,email"`
}

type GetUserRequest struct {
	ID int64 `json:"id"`
}

type CreateUserRequest struct {
	Name  string `json:"name" validate:"required,min=2"`
	Email string `json:"email" validate:"required,email"`
}

func GetUser(ctx context.Context, req *GetUserRequest) (*User, error) {
	// ...
}

func CreateUser(ctx context.Context, req *CreateUserRequest) (*User, error) {
	// ...
}

tygor generates TypeScript types:

// Code generated by tygor. DO NOT EDIT.
export interface User {
  id: number;
  name: string;
  email: string;
}

Call your API with full type safety:

const user = await client.Users.Get({ id: "123" });
// user: User (autocomplete works)

Try it now

Clone the Solid.js + Vite starter and start building:

bunx degit ahimsalabs/tygor-templates/starter-solid my-app
cd my-app && bun i && bun dev

Or React: bunx degit ahimsalabs/tygor-templates/starter-react my-app

Prerequisites: Go 1.21+, Node.js 18+

Quick Start

If you prefer to start from scratch rather than the example above:

1. Create your app with an export function

The CLI finds your app by scanning for any exported function that returns *tygor.App:

func SetupApp() *tygor.App {
	app := tygor.NewApp()

	users := app.Service("Users")
	users.Register("Get", tygor.Query(GetUser))      // GET request
	users.Register("Create", tygor.Exec(CreateUser)) // POST request

	return app
}

• Query handlers serve GET requests (query params in URL)
• Exec handlers serve POST requests (JSON body)

app := SetupApp()
http.ListenAndServe(":8080", app.Handler())

2. Generate TypeScript

# Generate types and manifest
tygor gen ./src/rpc

# With Zod schemas for client-side validation
tygor gen ./src/rpc --flavor zod

This creates:

• types.ts - TypeScript interfaces for all your Go types
• manifest.ts - Service registry for the client
• schemas.zod.ts - Zod schemas (with --flavor zod)

3. Call from TypeScript

import { createClient } from "@tygor/client";
import { registry } from "./rpc/manifest";

const client = createClient(registry, {
  baseUrl: "http://localhost:8080",
});

// Type-safe API calls
const user = await client.Users.Get({ id: 123 });
console.log(user.name); // autocomplete works

Development with Vite

The Vite plugin gives you hot reload, error overlay, and devtools:

npm install @tygor/vite-plugin

import { defineConfig } from "vite";
import { tygor } from "@tygor/vite-plugin";

export default defineConfig({
  plugins: [
    tygor({
      workdir: "../server",  // Path to your Go module
      build: "go build -o ./tmp/server .",
      start: (port) => ({ cmd: `./tmp/server -port=${port}` }),
    }),
  ],
});

The plugin automatically:

• Runs tygor gen on startup and file changes
• Hot-reloads your Go server with zero downtime
• Shows build errors in-browser
• Provides a devtools sidebar with API info

Your frontend state persists across server reloads. See @tygor/vite-plugin for full docs.

Why tygor?

• No IDL required. Go structs are your schema. Or use protobuf if you prefer schema-first.
• Standard HTTP/JSON. Debuggable with curl. Cacheable. Works with your existing infra.
• Tiny client. Proxy-based, <3KB. No per-endpoint generated code.
• Go-native. Works with net/http, your middleware, your patterns.

Who is this for?

Use tygor if you:

• Build fullstack apps with Go backend + TypeScript frontend
• Work in a monorepo (or want types to stay in sync)
• Prefer iterating on code over maintaining schema files
• Would use tRPC if your backend was TypeScript

Consider alternatives if you:

• Need multi-language clients → OpenAPI generators
• Need strict public API contracts → Connect/gRPC with protobuf

Features

Error Handling

Structured error codes that map to HTTP status:

return nil, tygor.NewError(tygor.CodeNotFound, "user not found")
// → HTTP 404, JSON: {"code": "not_found", "message": "user not found"}

Validation errors return CodeInvalidArgument automatically when validate tags fail.

Validation

Server-side validation with validator/v10 tags, client-side with generated Zod schemas:

type CreateUserRequest struct {
    Name  string `json:"name" validate:"required,min=2"`
    Email string `json:"email" validate:"required,email"`
}

See examples/zod for client-side validation with Zod.

Caching

Cache control for Query (GET) endpoints:

users.Register("Get", tygor.Query(GetUser).
    CacheControl(tygor.CacheConfig{MaxAge: 5 * time.Minute, Public: true}))

Interceptors

Cross-cutting concerns at app, service, or handler level:

app.WithUnaryInterceptor(loggingInterceptor)
service.WithUnaryInterceptor(authInterceptor)
handler.WithUnaryInterceptor(auditInterceptor)

Execution order: app → service → handler → your function.

Middleware

Standard HTTP middleware:

app.WithMiddleware(middleware.CORS(middleware.CORSAllowAll))

CLI Reference

tygor gen <outdir>           # Generate TypeScript types and manifest
  -p, --package    Package to scan (default: current directory)
  -f, --flavor     Add Zod schemas: zod, zod-mini
  -d, --discovery  Generate discovery.json for runtime introspection
  -c, --check      Check if files are up-to-date (for CI)

tygor check                  # Validate exports without generating

tygor dev                    # Start devtools server (used by Vite plugin)
  --rpc-dir        Directory with discovery.json
  --port           Server port (default: 9000)

Advanced: Programmatic Generation

You can also generate types programmatically, useful for custom build scripts:

tygorgen.FromApp(app).ToDir("./client/src/rpc")

Examples

Example	Description
react	React + Vite starter with type-safe API calls
zod	Client-side validation from Go validate tags
newsserver	Simple CRUD API to explore the basics

See all examples including auth, protobuf, and more.

Status

Important

tygor is pre-release. The API and protocol may change. Pin @tygor/client and tygor.dev to the same version.

License

MIT

Tiger image by Yan Liu, licensed under CC-BY.