With over 37,000 GitHub stars and used by teams at Y Combinator, Airbus, and Phantom, PostHog replaces an entire stack of paid analytics tools — Mixpanel, Amplitude, Heap, LaunchDarkly, Hotjar, and Google Analytics — with a single open-source platform where every tool shares a common event layer and user context. Product analytics captures events automatically or via manual instrumentation with HogQL (SQL) access for custom queries, while web analytics provides GA-like dashboards for traffic, conversions, and Core Web Vitals. Session replay records user interactions with DOM snapshots and network waterfall analysis, linking directly to errors and feature flag exposures. Feature flags safely roll out changes to specific cohorts with multivariate support and instant rollback, while experiments run A/B tests with automatic Bayesian significance calculations and revenue attribution. Error tracking captures stack traces linked to session replays and user properties for immediate reproduction context. AI observability monitors LLM generations, traces, token usage, latency, and costs across model versions. The managed data warehouse syncs 120+ external sources including Stripe, Postgres, Salesforce, and HubSpot alongside product events, queryable through a unified SQL editor. An MCP server enables AI agents in Cursor, Claude Code, or VS Code to query analytics and execute SQL directly. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

With over 9,000 GitHub stars and a focus on developer experience over legacy monitoring complexity, Highlight.io delivers a unified observability platform that correlates frontend user behavior with backend performance data in a single interface. The session replay engine captures high-fidelity DOM recordings showing exactly what users experienced, including console logs, network requests, page transitions, and user interactions, with configurable privacy redaction for sensitive content. Error monitoring automatically groups and deduplicates errors, surfaces affected user sessions, and provides full stack traces with source map support for minified production code. The logging pipeline ingests structured and unstructured logs from any backend service with automatic property extraction, full-text search, and configurable alerting thresholds. Distributed tracing tracks request flows across microservices with embedded links to associated sessions, errors, and logs for complete request lifecycle visibility. The metrics system collects custom application metrics alongside built-in web vitals and performance data for trend analysis and anomaly detection. Search across all telemetry types uses a unified query language with automatic attribute discovery and saved views for recurring investigations. Integrations connect with Slack, Discord, Linear, Jira, Vercel, and dozens of other developer tools for notification routing and workflow automation. SDKs cover React, Next.js, Vue, Angular, Python, Go, Ruby, Java, PHP, and Elixir with framework-specific instrumentation. Self-hosted deployment runs via Docker Compose with ClickHouse for analytics storage. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Backed by 12,400+ GitHub stars and positioned as the self-hosted alternative to FullStory and Hotjar, OpenReplay delivers the open-source session replay platform that keeps every byte of user behavior data on your own infrastructure. The JavaScript tracker captures pixel-perfect recordings of clicks, scrolls, form inputs, and navigation with automatic sensitive data masking, while simultaneously logging network requests, console errors, JavaScript exceptions, and Redux, VueX, MobX, NgRx, Pinia, and Zustand store state changes for complete technical context. DevTools mode reconstructs each session with full stack traces, GraphQL queries from Apollo and Relay, Fetch and Axios request payloads, CPU and memory metrics, and page speed waterfall charts — effectively giving developers a browser inspector tied to any user session. Product analytics surfaces conversion funnels, user journeys, click heatmaps, web vitals trends, and retention cohorts without requiring custom instrumentation. Co-browsing connects support agents to live user sessions with cursor control and WebRTC audio, enabling real-time assistance without third-party screen-sharing software. Integrations push session context into Sentry, Datadog, CloudWatch, Stackdriver, and Elastic for front-to-back debugging. Feature flags enable gradual rollouts with session-level targeting. The platform deploys to any cloud via Docker and Kubernetes with auto-scaling ingestion handling up to 50,000 sessions per month on the open-source edition. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPLv3 licensed.