The person behind Endpoint 51

Hi, I'm Simon O'Connor

I'm an Irish software developer and the author of Mastering APIs with Python, a 30-chapter book that takes you from your first requests.get() to deploying production services on AWS.

I wrote this book because most API tutorials stop at the happy path. The request succeeds, the JSON parses, the demo works. Then you ship something real and discover timeouts, rate limits, expired tokens, malformed payloads, and servers that lie. The book teaches the part that comes after the tutorial: error handling, validation, testing, and deployment, the same way you'd learn it on a production team.

Every project in the book is something I built and ran myself: the weather CLI with retry logic, the Spotify Music Time Machine with OAuth 2.0 and a real database, the FastAPI news aggregator, and the cloud deployment pipeline that ships it all to AWS. The free guides on this site come from the same place, including the production-grade pytest guide and the Spotify tutorial.

Endpoint 51 is operated by me as a sole trader in Ireland. When you buy the book, the support emails come from me, and the 30-day money-back guarantee is handled by me, usually within a day.