highlight.io is the open source full-stack monitoring platform for web applications, offering session replay, error monitoring, logging, traces, and dashboards.

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🚀 Overview

Highlight.io is an open-source observability platform that provides developers with tools to monitor, debug, and understand issues in their web applications. It captures user sessions, errors, logs, and performance traces, allowing teams to reproduce bugs quickly and gain insights into user behavior and app performance.

What problem does this project solve? It solves the challenge of invisible bugs and poor visibility in modern web apps by offering pixel-perfect session replays, real-time error tracking, log search, and distributed tracing in one unified platform.

Who is it built for? Developers, engineering teams, and companies building web applications with frameworks like React and Next.js who need affordable, self-hostable monitoring.

Why did you build it? To give developers a powerful, open-source alternative to expensive proprietary tools, enabling self-hosting and full control over their observability stack while supporting modern standards like OpenTelemetry.

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✨ Key Features

• Session Replay (pixel-perfect video replays of user sessions, console/network recording, privacy controls, session search) - helps reproduce user issues exactly as they happen.
• Error Monitoring (custom grouping, alerting, OpenTelemetry-powered) - catches exceptions before they impact users.
• Logging (searchable logs, alerts, ClickHouse-powered) - full-stack log analysis with embedded replays.
• Traces (distributed tracing, performance insights, OpenTelemetry support) - identifies bottlenecks in requests.
• Dashboards & APM (customizable visualizations, user analytics) - single pane for all observability data.
• Optional: Self-hosting for hobby/enterprise.

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🛠 Tech Stack

• Frontend: Next.js, React, TypeScript
• Backend: Go
• Database: PostgreSQL, ClickHouse, Redis
• Auth: Custom
• Hosting: Docker (self-host), cloud-hosted

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👥 Who Is This For?

This project is useful for:

• Developers who want to monitor frontend/backend errors and user sessions
• Teams looking for session replay and full-stack observability
• Indie makers building web apps needing free self-hosting

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📸 Screenshots / Demo

• Live demo: https://www.highlight.io
• GitHub: https://github.com/highlight/highlight

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🔥 Project Status

• 🟡 Maintained

Note: Acquired by LaunchDarkly in April 2025; cloud service migrating, but open-source repo remains active.

Last updated: 2026-03-24

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❓ FAQ

Is this project free?

Freemium / Open Source (Self-hosted hobby tier free forever; cloud pay-as-you-go starts at $50/month, business $800/month, enterprise custom.)

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Is the source code available?

Yes — https://github.com/highlight/highlight

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Can I contribute?

Yes — the project welcomes contributions via GitHub issues, pull requests, and feedback. Star the repo to show support.

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📬 Contact & Links

• Website: https://www.highlight.io
• GitHub: https://github.com/highlight/highlight
• Twitter/X: https://x.com/highlightio
• Email: security@highlight.io

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