Instrument, Monitor, Fix: A Hands-On Debugging Session

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You just shipped a new feature. Tests passed. CI’s green. Everything’s deployed. Life’s good… until the alerts start rolling in. Users reporting “weird stuff happening”, UI glitches, vague “it seems slow” reports, and that dreaded “can’t login” message. Well, this is shaping up to be a bad day. But… maybe not.

Watch this hands-on session to learn how to build it, break it, debug it, and go from “no idea what’s wrong” to fixing issues—all in one go. Since we’re serious developers (obviously), we’ll use Next.js and:

  • Setup Sentry from the ground up - including Errors, Session Replay, and Tracing
  • Learn ways to use Replays to understand the real user experience, and how to use Tracing to debug application issues
  • Leverage Sentry AI and the context of your application to understand what’s actually broken, and use Autofix to generate a fix - from root cause all the way to PR.

Use this workshop guide to follow along: Quickstart Guide.

This workshop has been presented at React Summit 2025, check out the latest edition of this React Conference.

Lazar Nikolov
Lazar Nikolov
02 Jun, 2025
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