Open-source Glassbox alternatives

PostHog is an open-source platform that bundles the tools product teams use to understand and improve what they ship. It captures event data, user sessions and errors in one place, and its newer self-driving mode aims to turn signals such as errors, rage clicks and failed queries into researched reports and pull requests that engineers review and merge.

The product suite includes product analytics with autocapture or manual instrumentation and SQL analysis, web analytics with a dashboard resembling Google Analytics, session replays for web and mobile, feature flags, experiments with statistical measurement, surveys, error tracking, logs, a data warehouse and a customer data platform. The back end is Python and the front end is React and TypeScript.

PostHog's repository license is listed as 'Other' on GitHub, so check which parts are open source and which are enterprise-only. It can be self-hosted, and the company also runs a managed cloud service. It suits product and engineering teams that prefer a single tool over separate analytics, flagging and replay vendors.

OpenReplay is an open-source experience platform that you host on your own infrastructure. It combines session replay, DevTools-level debugging context, product analytics and live cobrowsing, so teams can see how real users navigate, where they struggle and what errors they hit without sending sessions to a third party.

Because everything stays in your own cloud, it is pitched at teams that cannot hand customer data to an external vendor. Data can be masked, obscured or skipped at capture time before it reaches your servers, and a private mode redacts everything by default. A lightweight tracker sends data asynchronously to limit the impact on page performance, and SDKs cover frameworks such as React, Angular, Vue, Svelte, Next.js and React Native.

The README states it can be self-hosted for free on AWS, GCP, Azure and other platforms. The repository lists its licence as Other and its topics also reference feature flags, web vitals and real-user monitoring, so it spans debugging, product and support use cases.

Highlight, at highlight.io, is an open-source monitoring platform for developers. Its aim is to give teams one cohesive tool covering the front end and back end, instead of separate products for errors, logs and user sessions.

The core features are session replay, error monitoring and logging, with tracing and metrics also in scope. Console logs from the front end can be analyzed, and errors are embedded alongside the session in which they happened, so you can see what the user was doing beforehand. Session comments let teams discuss user frustration or bugs, there are integrations with other tools, and client SDKs install with a few lines of code.

You can sign up for the free-to-start hosted version at app.highlight.io, or deploy a hobby instance on Linux with Docker, sized at roughly 8 GB of memory, four CPUs and 64 GB of storage. The code is written in TypeScript and Go, and the repository lists the license as Other, so check the licence file for terms.