Your coding agent writes code fast. But when it breaks, it's debugging blind.
Replay gives your agent the runtime context it needs to find bugs — not guess at them.
The core insight
Replay captures what actually happened.
Not logs. Not stack traces. A deterministic recording of every DOM change, network request, and state update — the full runtime picture your agent has never had access to before.
Browser session
A bug occurs in the browser
Replay Recording
Every detail is captured
Agent gets context
Root cause is identified
Fix shipped
Your agent applies the fix
Works where you already work.
Same recording engine. Two ways to connect.
Replay MCP
Install Replay MCP in one command and connect it to Cursor, Claude Code, Copilot, or Windsurf. Your agent gets root cause and a specific fix automatically.
Read the docs →Replay Chrome Extension
Record a bug in your browser, get a plain-English fix to paste into your AI tool. No setup required.
Coming SoonCase Studies
Hear from Replay teams directly
“Before Replay We spent somewhere between 1–2 hours per day per dev in this reproducibility purgatory. The toll this was taking on our development velocity and our ability to respond and resolve issues was huge. We thought there must be a better way.”
Read full case study
Mark Probst
@VP Eng, Glide
“If I didn’t have Replay, it would have taken me several days or even weeks getting the debugger to run properly in all the dynamically loaded scripts, which is not easy. With Replay it took me half a day to figure it out and get a fix ready.”
Read full case study
Simeon Cheeseman
@Tablecheck, Principal Engineer
“The tools that we were using before were barely better than useless. You’d say thanks for the console log screenshot and spend 2–3 days trying to recreate the issues and finding it in the code. With Replay, all that wasted time has been eliminated.”
Read full case study
Shane Duff
@Pantheon, Front End Lead
Testimonials
See what time travelers are saying
“Next.js App Router is now stable in 13.4. Wouldn’t have been possible without Replay, we investigated so many (over 20) super complicated bugs that using traditional debugging would have cost us days to investigate.”
Tim Neutkins
@Co-author of Next.js
“I think Replay has a very good chance of creating a new category around collaborative debugging”
Guillermo Rauch
@Founder of Vercel
“When I see a hard-to-reproduce issue in GitHub, I ask for a replay.”
JJ Kasper
@Co-author of Next.js
“If I don't immediately know the answer to a bug, I immediately reach for Replay.io. It's like HMR for repros.”
Sebastian Markbåge
@React Maintainer
“Replay.io is galaxy brain tooling. Real gamechanger.”
Dan Abramov
@React Maintainer
“I think Replay has a very good chance of creating a new category around collaborative debugging”
Guillermo Rauch
@Founder of Vercel
“When I see a hard-to-reproduce issue in GitHub, I ask for a replay.”
JJ Kasper
@Co-author of Next.js
“If I don't immediately know the answer to a bug, I immediately reach for Replay.io. It's like HMR for repros.”
Sebastian Markbåge
@React Maintainer
“Replay.io is galaxy brain tooling. Real gamechanger.”
Dan Abramov
@React Maintainer
“Programmers typically reach for debuggers when they run out of ideas on how to fix their code. Now coders reach for time-travel debugging to understand their programs and not just when they want to fix a bug.”
Amjad Masad
@Founder Replit
“Fast forwarding and rewinding to breakpoints has saved me days(weeks??) while hunting down issues in @solid_js interruptible concurrent rendering.”
Ryan Carniato
@Solid Founder
“Replay.io gives me the tools I need to solve seemingly impossible bugs. It’s like the Redux DevTools, but for every line of code in your app.”
Mark Erikson
@Redux Maintainer
“Replay.io allows me to debug problems that would be impossible to debug by traditional means - it has saved me from countless hours of confusion and frustration.”
Lenz Weber-Tronic
@Redux Toolkit Maintainer
“I’m not sure if we could’ve shipped the last major version of RedwoodJS without Replay.”
Dom Saadi
@Maintainer of RedwoodJS
“Replay.io is so great! Today I had a hard-to-repro flow in development, so I recorded a replay to see how it works. I didn’t only find the bug, I discovered a performance improvement using Replay.”
Ives van Hoorne
@Co-founder CodeSandbox
“Current status: time-travel debugging Typescript's compiler. Replay is the hero tool I don't deserve. My dev life consists of 2 major eras now - I call them pre-Replay and post-Replay.”
Mateusz Burzyński
@OSS Contributor to Typescript
“Replay.io is from another planet where bug reports save you time, instead of eating up hours of debugging.”
Matt Pockock
@Full-time TypeScript educator
“Time travel is the obvious next step for the future of collaboratively inspecting and debugging applications.”
David Khourshid
@Founder of Stately.ai
“People use the word "game-changer" waaaaay too often. Very rarely does anything change the game. But this just might! I'm sharing it to all of my teams.”
Erik Rasmussen
@Author of Redux form and final form
“Replay.io is one of these experiences that first feels like magic – but after squashing your first bugs with it, you will quickly wonder how you ever worked without it”
Harald Kirschner
@Product Manager, VS Code
“Replay.io is the most significant leap forward for debugging since we introduced the step debugger”
Kenneth Auchenberg
@Developer Products, Stripe
“If a picture is worth a thousand words, a replay is worth a thousand pictures”
Zack Rosen
@CEO of Pantheon
“Recording and debugging flaky tests with Replay.io feels like hopping in Doc Brown’s DeLorean and flying back to the time of the crash!”
Gleb Bahmutov
@Distinguished Engineer, Cypress
“Before Replay.io, we spent somewhere between 1–2 hours per day per dev in this reproducibility purgatory”
Mark Probst
@Glide apps, VP Eng
Stop debugging for your agent.
Let Replay do it.
Free to get started. No credit card required.