xlens isn't a replacement for testing, replay or error monitoring. It closes the loop they leave open: from a problem real users hit, to the line of code, to a verified fix.
| Capability | xlens | Playwright | PostHog | FullStory / LogRocket | Sentry | Datadog RUM |
|---|---|---|---|---|---|---|
| Maps findings to component → file:lineOthers map JS errors through source maps, but not clicks, forms or UX issues. | ✓ | — | — | — | ◐ | ◐ |
| Real-user sessionsPlaywright drives scripted, synthetic browsers. | ✓ | — | ✓ | ✓ | ✓ | ✓ |
| Dead and rage clicks | ✓ | — | ✓ | ✓ | ✓ | ✓ |
| Root cause found in codeFor example, a validation pattern that rejects its own placeholder. | ✓ | — | — | — | ◐ | — |
| Funnels from real paths | ✓ | — | ✓ | ✓ | — | ◐ |
| Writes the fix and opens a PRAI fix features elsewhere focus on errors and exceptions. | ✓ | — | — | — | ◐ | ◐ |
| Verifies the fix on later buildsxlens runs a one-sided z-test on the issue rate in builds after the fix. | ✓ | — | — | — | ◐ | — |
| MCP server for coding agents | ✓ | ✓ | ✓ | ◐ | ✓ | ✓ |
| Self-hosted, no cloud dependency | ✓ | ✓ | ◐ | ◐ | ✓ | — |
| Never captures input valuesOthers mask inputs by default or by configuration. xlens never sends them. | ✓ | n/a | ◐ | ◐ | ◐ | ◐ |
| Price | $0 · MIT | Free · Apache-2.0 | Free tier, then usage | Paid, free tier | Free tier, then usage | Usage-based |
✓ yes · ◐ partly · — no · Based on public docs as of Nov 2026. Spotted a mistake? Open an issue.
Playwright checks the paths you thought of, in a synthetic browser, before release. xlens watches the paths real people take after release, and finds the ones you didn't think of: the coupon button that does nothing, the postcode field that rejects its own example. When xlens fixes an issue, your Playwright suite is one of the checks that has to pass.
PostHog is a broad product platform: analytics, flags, experiments and replay. xlens is narrower. It starts from your source, so every finding comes with a file, a line and, where code can fix it, a pull request.
Session replay lets a person watch what went wrong. xlens has no replay. It turns the same signals into ranked issues that point at a call site, and then does the fixing.
Error monitors are excellent at exceptions. Many UX problems never throw: dead clicks, validation loops, CTAs nobody sees on mobile. xlens covers those, and checks whether each fix actually helped on later builds.
❯ npm i @xlens/sdk && npm i -D @xlens/plugin @xlens/cli ❯ npx xlens init Created xlens.config.json ❯