Official Lettr SDKs

Official Lettr SDKs for all major programming languages. Each SDK has a guide to get you sending in minutes — follow the card for your language, then use the API reference for full endpoint details.

Official SDKs

Node.js

npm install lettr

PHP

composer require lettr/lettr-php

Python

pip install lettr

Go

go get github.com/lettr-com/lettr-go

Rust

cargo add lettr

Java

<dependency>
  <groupId>com.lettr</groupId>
  <artifactId>lettr-java</artifactId>
  <version>1.1.0</version>
</dependency>

Framework Integrations

Laravel

Official Laravel package

Next.js

Send from Next.js apps

Nuxt

Send from Nuxt apps

Flask

Send from Flask apps

FastAPI

Send from FastAPI apps

Serverless

AWS Lambda, Vercel, Cloudflare

SDK Features

All SDKs include:

Feature	Description
Type definitions	Full TypeScript/type hints support
Error handling	Structured error responses
Automatic retries	Retry on transient failures
Webhook verification	Built-in signature verification
Rate limiting	Automatic rate limit handling

Source & Contributing

SDKs are open source on GitHub. Each repository’s README has install notes and a hello-world example; full usage lives in the per-language guides above and the API reference.

Contribution Guide

Learn how to contribute to our SDKs

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Documentation

Quickstart

Learn

Integrations

Resources

Official Lettr SDKs

Official SDKs

Node.js

PHP

Python

Go

Rust

Java

Framework Integrations

Laravel

Next.js

Nuxt

Flask

FastAPI

Serverless

SDK Features

Source & Contributing

Contribution Guide

​Official SDKs

Node.js

PHP

Python

Go

Rust

Java

​Framework Integrations

Laravel

Next.js

Nuxt

Flask

FastAPI

Serverless

​SDK Features

​Source & Contributing

Contribution Guide

Official SDKs

Framework Integrations

SDK Features

Source & Contributing