Replay QA

Replay QA is an autonomous AI testing platform built by Replay.io, a team founded by ex-Mozilla engineers. It targets the growing gap between AI-accelerated development and traditional QA processes by autonomously exploring web apps, writing its own Playwright tests, recording every session, and filing structured bug reports with root cause analysis and suggested fixes. Users can get started with just a URL — no test suite, no configuration, no credit card required.

What It Is

Replay QA is an AI-driven quality assurance tool designed for web applications. It operates in two modes: continuous testing via GitHub repository integration (acting as a quality gate on every PR or main-branch push), and on-demand testing by simply dropping in a URL. The underlying recording engine captures every DOM change, network request, and state update deterministically — not as a video or log file, but as a full reproducible session that can be stepped through in detail.

How It Works

The tool follows a four-step automated pipeline:

• Give it a URL — point Replay QA at any web app, from a marketing site to an internal tool
• Discovers journeys and writes tests — the AI explores the app and generates Playwright tests autonomously
• Runs tests with Replay recording — every test run is captured with the full recording engine
• Files detailed bug reports — each bug comes with a recording, root cause analysis, and a suggested fix

For GitHub-connected repos, root cause and fix suggestions are posted directly on the pull request. For URL-based testing, a full bug report is delivered in minutes.

Who It's Built For

Replay QA targets two distinct audiences. For engineering teams, it acts as a continuous quality gate that installs via a GitHub App with no pipeline configuration. For solo builders, vibe coders, internal tool developers, and agencies, the URL-drop mode requires zero setup and no testing knowledge. The tool also exposes a Replay QA API for software factories or AI coding platforms that want to embed automated QA as a quality gate for every app they generate.

Technology and Architecture

Replay.io's recording engine — the foundation of Replay QA — has been in production use by engineering teams at companies including Vercel, Glide, and Pantheon, according to the company's website. The engine performs deterministic capture of application state, enabling time-travel debugging. Replay QA layers autonomous AI exploration and test generation on top of this engine. The platform also offers Private Cloud and On-Prem deployment options for organizations requiring dedicated data ownership or self-hosted infrastructure.

Team and Background

Replay.io was founded by Brian Hackett, who holds a Stanford Ph.D. and spent a decade at Mozilla working on the Firefox browser engine. The team includes Mark Erikson, the maintainer of Redux and creator of Redux Toolkit, and Dominik Seifert, who holds a Ph.D. in systems analysis. The company operates as a distributed global team and describes its mission as making software development faster and more accessible by making the invisible visible.

Current Status

Replay QA is actively available with a free tier requiring no credit card. The product has evolved from Replay's original time-travel debugging tool into a full autonomous QA platform, reflecting the company's stated pivot toward AI-built app testing. The GitHub integration, URL-based testing, and API access are all live and in production.