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Meet Optic

Understand your APIs, know when they change

Optic watches real traffic to understand your API behavior and helps developers with API documentation and testing. With Optic every API change is documented, reviewed, and approved before getting deployed.

StarOpen Source, Free, Developed in the Open
Featured Tutorial (15 mins): Document your API using real traffic
Learn how to add Optic to an existing API and document all the endpoints in minutes.

What People Say About Optic
Optic is a smart, simple, and straightforward solution to a real world problem every company faces.
Kin Lane
The API Evangelist Chief Evangelist, Postman
At we’re aggregating data from hundreds of different back-end sources, many of which have constantly changing data models. Optic enables us to create self-documenting APIs and can proactively generate alerts when the shape of the data from any of our back-end sources unexpectedly changes.
Nathan Clevenger
FOUNDER DRIV.LY Serial Entrepreneur
Traffic-driven API development and ops is the the future of handling the skyrocketing complexity of API landscapes. Thats is why I am really excited to see efforts like Optic.
Zdenek Nemec


Document your API, know when it changes

Optic gives developers a simple workflow for maintaining an accurate, up-to-date API Contract. The tool makes it easy to document new endpoints, detect unplanned changes to the API behavior, and update the API Contract when planned API changes have been released.

Document your API in 10 minutes ➜


Discuss API Changes during Code Review

Optic adds an API Changelog to every Open Pull Request. Now your team can talk about both "API Changes" and "File Changes" during code review.

Add Optic to your API Workflow ➜


Test your API with Optic

Use traffic from your Tests and from Staging environments to verify each version of your API meets its contract, before it gets deployed to users. Get the benefits of Contract Tests, without writing and maintaining them.

Test your API with Optic ➜

DEMO: GitHub's API in Optic

Optic's UI is like a Git client, but for reviewing API diffs, finding API breaks/bugs early, and updating your specifications. In these two demos you can explore what it's like to use Optic with GitHub's API.
Hover to Start Interactive Demo

Works Everywhere

Works with your code, infrastructure, and tools

All your API Frameworks
Ruby on Rails
Looking for your framework? Request it here
Deployed Environments
Azure Application Gateway
AWS API Gateway
AWS Lambda
Looking for your infrastructure tool? Request it here

The New API Toolchain

API-First Workflows, built for Developers, without YAML

API Test Coverage

Imagine Code-Coverage, but for APIs. Teams use coverage to understand how good their API tests are today, and provide confidence during release.

API Changelogs in Every Pull Request

What if it were easy to talk about API Changes during Code Review? Optic's GitBot adds an accurate API changelog to every Pull Request that changes the API contract. Suggest changes, discuss improvements, build a better API, together.

Design Consistent APIs

Optic built an approach to linting API Contracts that runs right in CI, and only gives you feedback about changes you're about to make, not the old endpoints you'll never go back and fix. It's simple, and makes it easy to desing great APIs together.

Fail your Tests when the API Changes

When your existing tests are run with Optic, you gain the ability to fail the test suite when the API contract is not met. With Optic it is easy to verify your API contract without rewriting the tests you already have.

We're here to help your team build a great API

Explore our docs, our live demos and read about the workflows Optic enables. When you are ready, set Optic up (it takes 10 mins) or have a conversation with the Optic maintainers for help.

When the CLI is installing, be sure to join the community.