VNHAX
vnhax
Explore Repos
Effect-TS/effectPublic
280
Fork740
11,400
3 branches · 14 tags
E
Effect-TS Teamrelease: Effect 4.0.0 LTS stable release milestone
3d7b88e1 day ago
packages/effect
core: Effect 4.0 LTS runtime and fiber scheduler
1 day ago
packages/schema
schema: zero-cost runtime validation replacing Zod
2 days ago
packages/platform
platform: multi-runtime HTTP, FileSystem & Worker APIs
3 days ago
docs
docs: add interactive guides for Effect 4.x migration
yesterday
LICENSE
legal: MIT license
3 years ago
README.md
docs: announce Effect 4.x LTS with fiber benchmarks
1 day ago
package.json
release: 4.0.0 LTS
1 day ago
README.md
Verified Technical Teardown
EFFECT 4.X LTS (ACTIVE)11.4K+ STARSTYPESCRIPT 5.9+ / TS 731 PACKAGESLICENSE: MIT
Effect - The Missing Standard Library for TypeScript
Effect-TS / effect — Production TypeScript Runtime

Effect: The Standard Library for Production TypeScript

Effect is a library for building robust, maintainable, type-safe, and production-grade applications in TypeScript. It helps you handle the hard problems at scale: typed errors, dependency injection, structured concurrency, scheduling, tracing, and unified schema validation.

Effect<A, E, R>
Tri-channel Type Signature
Fibers
Lightweight Green Threads
0 Unhandled
Guaranteed Type-Safe Errors
OpenTelemetry
Built-in Distributed Tracing
Quick Start

Installation

npm install effect
index.ts — Idiomatic Effect Program
import { Effect, Console } from "effect";

// Compose computations declaratively without triggering immediate execution
const program = Console.log("Hello from Effect 4.x!");

// Execute the effect through the runtime fiber scheduler
Effect.runSync(program);
REQUIREMENTS

TypeScript & Runtime Requirements

Effect is engineered to take full advantage of TypeScript's strongest type inference engine. Verify your project meets these compiler constraints:

📘 TypeScript 5.9 or newer & TypeScript 7

TypeScript 5.9+ is the required minimum. TypeScript 7 is strongly recommended for the best type-checking performance and full compatibility with Effect's native TypeScript language tooling (tsgo).

🟢 Node.js 18 or newer (Node.js 22.16+ Recommended)

Node.js 18+ is the general baseline runtime for running Effect on Node.js. Specific integration packages require newer runtimes; for instance, @effect/sql-sqlite-node requires Node.js 22.16 or newer for native SQLite bindings.

tsconfig.json — Strict Type-Checking Configuration
{
  "compilerOptions": {
    "strict": true,
    "exactOptionalPropertyTypes": true,
    "noUncheckedIndexedAccess": true,
    "target": "ES2022",
    "module": "NodeNext",
    "moduleResolution": "NodeNext"
  }
}
ECOSYSTEM

Official Effect Packages (32)

effectCore

Core runtime, lightweight green-thread fiber system, typed errors, and structured concurrency.

npm install effect
@effect/platform-browser

Web platform abstractions for browser DOM, fetch, storage, and worker communications.

npm install @effect/platform-browser
@effect/platform-bun

Ultra-fast Bun runtime integration leveraging Bun native APIs.

npm install @effect/platform-bun
@effect/platform-deno

Deno runtime bindings for file system, streams, and subprocesses.

npm install @effect/platform-deno
@effect/platform-node

Node.js production runtime with native streams, file system, and HTTP server.

npm install @effect/platform-node
@effect/platform-node-shared

Shared utility layer for Node-compatible runtimes and toolchains.

npm install @effect/platform-node-shared
@effect/sql-clickhouse

High-throughput analytical OLAP database driver with stream decoding.

npm install @effect/sql-clickhouse
@effect/sql-d1

Cloudflare D1 edge database driver with transaction and batching support.

npm install @effect/sql-d1
@effect/sql-libsql

Turso and LibSQL distributed edge SQLite client with embedded replicas.

npm install @effect/sql-libsql
@effect/sql-mssql

Enterprise Microsoft SQL Server client with connection pooling and typed parameters.

npm install @effect/sql-mssql
@effect/sql-mysql2

MySQL 8 and MariaDB async connection pool with typed statement execution.

npm install @effect/sql-mysql2
@effect/sql-pg

PostgreSQL connection manager with connection pooling, migrations, and streaming.

npm install @effect/sql-pg
@effect/sql-pglite

Embedded WASM Postgres in-process driver for Node, browser, and edge testing.

npm install @effect/sql-pglite
@effect/sql-sqlite-bun

Native Bun SQLite bindings with compiled C++ execution speed.

npm install @effect/sql-sqlite-bun
@effect/sql-sqlite-do

Cloudflare Durable Objects embedded SQLite storage driver.

npm install @effect/sql-sqlite-do
@effect/sql-sqlite-nodeNode 22.16+

Node.js SQLite integration using node:sqlite (Requires Node.js 22.16+).

npm install @effect/sql-sqlite-node
@effect/sql-sqlite-react-native

Offline-first SQLite persistence driver for React Native iOS and Android apps.

npm install @effect/sql-sqlite-react-native
@effect/sql-sqlite-wasm

In-memory and IndexedDB-backed SQLite compiled to WebAssembly.

npm install @effect/sql-sqlite-wasm
@effect/ai-anthropic

Anthropic Claude 3.5 Sonnet & Opus client with typed streaming and tool calling.

npm install @effect/ai-anthropic
@effect/ai-openai

OpenAI GPT-4o, o1, and embeddings client with structured JSON output schemas.

npm install @effect/ai-openai
@effect/ai-cloudflare

Cloudflare Workers AI edge model inferences with zero cold starts.

npm install @effect/ai-cloudflare
@effect/ai-typesafe

End-to-end typed schema validation for AI agents, prompt outputs, and tool dispatch.

npm install @effect/ai-typesafe
@effect/ai-openai-compat

Drop-in driver for local models (Ollama, vLLM, LM Studio) and third-party APIs.

npm install @effect/ai-openai-compat
@effect/ai-openrouter

Unified multi-model API router accessing 200+ frontier and open-weight models.

npm install @effect/ai-openrouter
@effect/atom-react

Fine-grained reactive state atoms and fiber subscription hooks for React 18 & 19.

npm install @effect/atom-react
@effect/atom-solid

Solid.js reactive signals powered by Effect concurrent runtime and error channels.

npm install @effect/atom-solid
@effect/atom-vue

Vue 3 Composition API refs and reactive bindings linked to Effect fibers.

npm install @effect/atom-vue
@effect/opentelemetry

Zero-overhead OpenTelemetry tracing, spans, baggage, and metrics propagation.

npm install @effect/opentelemetry
@effect/vitest

Vitest integration providing effect-aware it.effect test runners and assertions.

npm install @effect/vitest
@effect/docgen

Automated documentation and API website generator from TypeScript docstrings.

npm install @effect/docgen
@effect/doctest

Automated test runner that type-checks and verifies code blocks in markdown docs.

npm install @effect/doctest
@effect/openapi-generator

Compiles Effect Schema definitions directly into OpenAPI 3.1 specifications.

npm install @effect/openapi-generator
LTS RELEASES

Long-Term Support: Effect 4.x & Effect 3.x

Teams depend on Effect for production architectures they expect to run for years. Effect provides clear long-term support (LTS) lifecycle stability:

LTSEffect 4.x

Active Long-Term Support milestone. Incorporates zero-cost fiber scheduling, unified Schema validation, optimized microtask dispatching, and full TypeScript 7 forward compatibility.

MaintenanceEffect 3.x

The established major release powering thousands of production services. Receives critical security patches and backwards-compatible maintenance updates.

GuideMigration Guide

Upgrading from Effect 3.x to 4.x is smooth with automated codemods and the comprehensive MIGRATION.md guide.

Enterprise & Community Partnership

Let's Talk

Whether your team is considering Effect, rolling it out, or already running it in high-throughput production, the core team would love to hear from you:

💬 Talk to the Maintainers

Introduce your team on Discord or email contact@effectful.co. Happy to connect privately on Slack or Discord for feedback and architectural guidance.

🛡️ Production Support

Exploring dedicated support for mission-critical enterprise systems. If your organization has specific SLA, vulnerability auditing, or private roadmap needs, reach out directly.

🚀 Adoption Help

Official Adoption Partners offer hands-on implementation, consulting, team extension, staff training, and commercial support.

License: MIT License

Effect is 100% open-source software, free for both personal and enterprise commercial use.

View LICENSE ↗