Open-source alternatives to Web Vitals

react-ga is a Google Analytics React wrapper and client that provides a programmatic interface for integrating web analytics into React applications. It serves as a tool for recording user interactions, virtual page views, and custom dimensions to measure engagement within web applications. The project features a wrapper-based API that delegates high-level functions to the Google Analytics API. It includes an environment-based logic branching system with a test mode for inspecting analytics calls and verifying data transmission without affecting production servers. The library covers a broad

Countly is a self-hosted product analytics and engagement platform that tracks user behavior across mobile, web, and desktop applications. It collects and analyzes device properties, user actions, and session lifecycle data to understand engagement patterns, while also providing crash reporting, push notification delivery, and A/B testing capabilities. The platform is designed for privacy-first deployment, with built-in consent management and the ability to run entirely on private infrastructure. The platform distinguishes itself through its comprehensive feature set that combines analytics w

This is a backend-as-a-service SDK that connects web and mobile applications to a suite of cloud services. It provides a unified interface for managing user identity, executing serverless logic, and handling cloud object storage. The toolkit is characterized by its real-time data synchronization, which allows NoSQL document data to stay consistent across multiple clients with built-in offline persistence. It facilitates secure user access through a variety of identity providers and manages serverless function invocation to execute backend logic in response to HTTPS requests or database events

Bullet is an Active Record performance monitor and query profiler for Ruby on Rails applications. It serves as a diagnostic utility to identify inefficient database access patterns, flag redundant requests, and suggest eager loading strategies to improve response times. The tool specifically detects N+1 queries, missing counter caches, and unused eager loading. It monitors these patterns across both standard web requests and background jobs, identifying records that are fetched but never accessed to reduce memory usage and query overhead. Analysis is supported by a system that intercepts dat

PerfView is a set of integrated profiling and tracing tools built on Windows Event Tracing for Windows (ETW), designed to diagnose CPU, memory, and ETW-based performance issues in .NET applications. It captures ETW events to analyze runtime behavior, CPU usage, and memory allocations, serving as a .NET performance profiler that measures both CPU time and garbage collection events. The tool distinguishes itself with a diff comparison engine that compares two performance traces side-by-side to highlight changes in method costs and event rates. It renders profiled call stacks as flame graphs whe

This project is a personal technical blog and frontend development knowledge base. It serves as a website for publishing study notes, technical articles, and interview preparation materials focused on professional web development. The project includes a specialized utility for migrating knowledge base content from the Yuque platform into portable external formats. It also implements a secure authentication system using the OAuth2 protocol to connect third-party authorization services. Additional capabilities cover web performance analysis for identifying technical bottlenecks through site sp

Node-clinic is a performance profiling suite for Node.js designed to diagnose CPU bottlenecks, memory leaks, and asynchronous event loop issues. It provides specialized diagnostic tools for visualizing asynchronous flows, generating CPU flame graphs, and analyzing heap memory allocation. The suite includes a CPU flame graph tool to identify functions consuming the most processing time, a heap memory analyzer to track object allocation and leaks, and an asynchronous I/O profiler to map operation flows and find event loop bottlenecks. These tools cover broader capabilities in CPU execution pro

AngularFire is a set of tools for connecting applications to Firebase services. It provides a library of client-side interfaces for managing authentication, object storage, NoSQL databases, and serverless functions. The project utilizes observables and dependency injection to integrate cloud services into the application hierarchy. It features a reactive interface for streaming real-time data, managing document-based databases, and tracking authentication state as a continuous stream of tokens. The platform covers a broad range of cloud capabilities, including identity verification, binary f

This project provides reference implementations for integrating iOS applications with Firebase backend services. It covers the setup of user authentication, real-time data synchronization, and cloud storage for mobile clients. The repository demonstrates the use of a serverless mobile backend, including the execution of cloud functions and the management of remote application configurations. It also includes implementations for identity verification using Google accounts and the delivery of mobile push notifications. The codebase covers broader capability areas such as application stability

Reactime is a browser extension designed for debugging and profiling React applications. It provides a specialized interface for monitoring component hierarchies, tracking state transitions, and analyzing data flow within complex component trees. The tool distinguishes itself through time-travel debugging capabilities, which allow developers to capture and replay state snapshots to isolate logic errors. It also features a dependency graph mapper that visualizes the relationships between providers and consumers, clarifying how information is distributed throughout an application. Beyond core

Async-profiler is a sampling profiler for Java applications that tracks CPU time and stack traces across execution frames to identify performance bottlenecks. It is designed to capture profiling data without introducing timing bias. The project provides capabilities for JVM memory analysis to locate native and heap allocation hotspots and memory leaks. It also includes system contention analysis to identify resource bottlenecks through the tracking of contended locks and hardware performance counters. The tool converts raw profiling data into visual performance reports, including interactive

FlutterFire is a set of plugins and libraries that provide a Firebase SDK for applications built with the Flutter framework. It functions as a cloud services wrapper that maps Firebase cloud APIs to the Dart programming language, enabling backend integration for cloud data storage, user authentication, and serverless function execution. The project uses a plugin-based modular architecture to separate different cloud services into independent packages. It employs platform-interface abstractions and method-channel-based native interoperability to communicate with native Android and iOS SDKs thr

SvelteStorm is a specialized integrated development environment built for creating, editing, and debugging Svelte applications. The workspace provides a desktop code editing environment equipped with syntax highlighting, a file directory tree explorer, split-screen document viewing, code search tools, and an integrated terminal for executing shell scripts and terminal commands. The environment includes dedicated debugging and monitoring tools that generate real-time component hierarchy graphs, track live state values, and record application states to allow stepping backward and forward throu

53AIHub is a centralized orchestration platform for deploying and managing AI agents and prompts across multiple large language model providers. It functions as a multi-model AI gateway and an operation portal for AI services, providing a unified interface to coordinate agents and prompts from various external platforms. The project distinguishes itself as a white-label AI portal designed for self-hosted infrastructure, allowing for full control over operational data on private servers or containers. It includes a comprehensive AI SaaS administration layer with a multi-tenant subscription eng

Umami is a self-hosted, privacy-focused web analytics platform designed to provide full control over infrastructure and user data. It captures website traffic and visitor behavior through anonymous tracking methods that avoid cookies, browser fingerprinting, and the storage of personally identifiable information. The platform distinguishes itself through a comprehensive suite of behavioral analysis tools, including session replays, heatmaps, and cohort-based retention reporting. It features a multi-tenant architecture that allows teams to manage multiple websites within a single, collaborativ

Canal is a database replication middleware that performs change data capture by simulating a database replica. It monitors transaction logs to stream incremental data modifications to downstream systems in real time, acting as an event streaming infrastructure that transforms low-level binary logs into structured, consumable message streams. The project distinguishes itself through a high-throughput architecture that utilizes concurrent multi-threaded parsing and stateful log position tracking to ensure reliable data delivery. It employs a pluggable sink architecture that decouples data extra

Selenium is a comprehensive browser automation framework that provides a standardized interface for controlling web browsers to perform automated tasks, user interactions, and data extraction. It functions as a cross-browser testing tool, enabling developers to execute identical automation scripts across various browser engines and operating systems to ensure consistent application behavior. By implementing the WebDriver protocol, it maps high-level automation commands to browser-specific drivers using a standardized HTTP-based wire protocol. The project distinguishes itself through its distr

The diagnostics project provides a cross-platform diagnostic infrastructure and command-line toolkit for monitoring runtime performance, analyzing memory dumps, and troubleshooting applications. It features a custom inter-process communication protocol for command and telemetry exchange across platforms, a low-overhead event pipe mechanism for streaming real-time diagnostic events and performance counters from running processes, and automated remote symbol resolution for stack trace analysis. The platform includes native debugger extensions that integrate with standard debuggers to inspect ma

Apache JMeter is a Java-based performance testing tool and multi-protocol traffic simulator used to analyze the stability and scalability of servers and networks. It functions as a distributed load testing framework that coordinates remote worker nodes from a single controller to generate high volumes of concurrent traffic. The project is distinguished by its ability to simulate traffic across diverse backend systems, including HTTP, JDBC, LDAP, JMS, FTP, and TCP. It provides a headless command-line interface for automated execution and a reporting system that transforms raw sample logs into

fio is a storage performance benchmarking tool and synthetic I/O workload generator. It functions as a storage device profiler and I/O trace replay engine, enabling the measurement of throughput and latency for storage devices and file systems. The project is distinguished by its ability to act as a distributed storage stress tester, managing multiple remote server backends via a single controller to evaluate network storage. It also includes specialized capabilities for storage deduplication analysis by generating redundant data buffers to test the efficiency of deduplication subsystems. Th

k6 is a developer-centric load testing suite and command-line load generator designed for network performance validation. It functions as a JavaScript load testing tool that utilizes a Go-based runtime engine to simulate concurrent user traffic and validate API responses across HTTP, gRPC, and WebSockets. The project distinguishes itself by using code rather than a graphical interface to define workload scenarios and performance thresholds. It features a pluggable protocol architecture and an extension ecosystem that allows for the addition of custom protocols and specialized testing capabili

pyinstrument is a statistical sampling profiler for Python that records the call stack at regular intervals to identify performance bottlenecks with low overhead. It tracks wall-clock time, including I/O and external service calls, and provides specialized profiling for asynchronous programs by attributing time spent awaiting tasks to the calling function. The project converts captured execution data into interactive HTML reports, JSON, and flamecharts. It includes a call stack visualizer to simplify the analysis of execution paths and supports the profiling of individual cells within interac

Elementor is a visual page builder for WordPress that provides a drag-and-drop interface for creating responsive layouts and custom themes. It functions as a comprehensive design system manager and theme builder, allowing for the creation of global website components such as headers, footers, and archive pages without writing code. The platform distinguishes itself through a dedicated popup builder with custom trigger conditions and a visual landing page creator that utilizes pre-made kits. It includes a global style registry to synchronize fonts and colors across all site elements and a widg

This repository is a technical documentation site and a collection of guides and references for implementing networking, security, and cloud infrastructure services. It functions as a static-site generated portal and a headless content platform, separating source files from the presentation layer to enable flexible rendering. The project utilizes markdown-based documentation stored in a version-controlled Git repository. It provides specialized technical content including an AI platform documentation for building agents and managing inference, a cloud infrastructure guide for DNS and CDN conf

This project is a command-line tool and build toolchain used to bootstrap React web applications. It serves as a project bootstrapper and single-page application scaffold, providing a pre-configured development environment, folder structure, and build pipeline. The toolchain integrates a frontend development server with live reloading and error overlays to accelerate the iterative coding process. It handles production asset bundling by minifying code and generating hashed assets for deployment, and it includes a configuration suite for generating the service workers and web manifests required

gstack is an AI agent framework and development workflow system designed to automate the software development lifecycle. It coordinates specialized AI personas to manage tasks across product design, engineering management, and quality assurance, transforming product intent into technical specifications and final releases. The project is distinguished by its deep integration of headless browser automation and semantic code memory. It utilizes a persistent Chromium daemon for web scraping and visual auditing, and implements a searchable knowledge base that logs architectural decisions and repos

Taiko is a browser automation framework and web end-to-end testing library used to perform programmatic user actions and verify application behavior. It functions as a headless browser testing tool capable of simulating real interactions and asserting page states in Chromium and Firefox. The project includes a browser interaction recorder that captures live actions and exports them as executable JavaScript automation scripts. It also serves as a web accessibility auditor, analyzing pages to detect accessibility violations and ensure compliance with inclusive design standards. The framework c