Open Source Projects using C++
A curated collection of the 80 best open source software using C++. Find the most popular and trending open source projects to learn from, contribute to, or use in your own projects.
Run open-source LLMs locally on your own machine
Stars
183,788Last commit
19 hours agoLicense
MIT
Runs open-source language models locally with a simple setup, plus optional cloud access for larger models when local hardware isn't enough.
Open Source Alternative to:
AI coding agent that works inside your terminal
Stars
129,841Last commit
13 hours agoLicense
Apache-2.0
Terminal-based AI coding agent that inspects files, edits code, runs commands, and integrates into CI pipelines using OpenAI's Codex models.
Open Source Alternative to:
Run LLMs locally with minimal setup, maximum hardware support
Stars
131,662Last commit
6 hours agoLicense
MIT
C/C++ inference engine for large language models, supporting quantization, multi-GPU, Apple Silicon, and an OpenAI-compatible server across a wide range of hardware.
Open Source Alternative to:
Self-hosted remote desktop you fully control
Stars
126,279Last commit
3 days agoLicense
AGPL-3.0
Cross-platform remote desktop software that runs on your own servers, giving you full data control as a direct alternative to TeamViewer and AnyDesk.
Open Source Alternative to:
Self-hosted photo and video backup for your own server
Stars
116,617Last commit
7 hours agoLicense
AGPL-3.0
Back up, organize, search, and browse your personal photo and video library on your own server, with no third-party cloud access.
Open Source Alternative to:
High-throughput, memory-efficient serving engine for LLMs
Stars
94,109Last commit
6 hours agoLicense
Apache-2.0
Inference and serving engine for large language models, built for speed and hardware efficiency with an OpenAI-compatible API and support for a wide range of open models.
Open Source Alternative to:
Free 2D and 3D game engine for cross-platform projects
Stars
118,658Last commit
1 day agoLicense
MIT
Build 2D, 3D, and XR games with a full-featured engine that includes its own scripting language, scene editor, and export tools for multiple platforms.
Open Source Alternative to:
Share files securely across all devices without servers
Stars
94,877Last commit
2 days agoLicense
Apache-2.0
Free, open-source file sharing tool for nearby devices. Cross-platform support with end-to-end encryption, no registration required, automatic device discovery.
Open Source Alternative to:
The leading distributed search and analytics engine
Stars
78,314Last commit
6 hours agoLicense
Unknown
Elasticsearch is an open-source, RESTful search engine designed for scalability, reliability, and easy management.
Open Source Alternative to:
AI workspace for docs, projects, and wikis you control
Stars
77,551Last commit
11 days agoLicense
AGPL-3.0
Open source collaborative workspace combining notes, databases, and AI with full data ownership, offline support, and self-hosting options.
Open Source Alternative to:
Coding agent that runs on local and open-weight models
Stars
68,604Last commit
9 days agoLicense
Apache-2.0
Coding agent that lets LLMs write and execute code, manage files, and control your computer using local or low-cost models.
Open Source Alternative to:
An independent browser engine built from scratch, not a fork
Stars
66,571Last commit
8 hours agoLicense
BSD-2-Clause
Open source web browser with its own engine, built from scratch without Blink, WebKit, or Gecko. Non-profit backed, no search deals, no user monetization.
Open Source Alternative to:
Free, open-source software for video recording and live streaming
Stars
77,753Last commit
3 days agoLicense
GPL-2.0
OBS Studio offers high-quality video recording and live streaming capabilities, supporting multiple platforms and providers.
Open Source Alternative to:
Real-time monitoring for systems and applications
Stars
81,019Last commit
13 hours agoLicense
GPL-3.0
Powerful, efficient, and user-friendly monitoring solution for servers, containers, and applications with instant insights and alerts.
Open Source Alternative to:
Run open-source AI models privately on your own device
Stars
77,350Last commit
1 year agoLicense
MIT
GPT4All runs open-source language models locally on Windows, macOS, and Linux with no cloud dependency, keeping your data on your machine.
Open Source Alternative to:
Fast GPU-accelerated terminal with native UI design
Stars
62,367Last commit
12 hours agoLicense
MIT
Experience blazing-fast terminal performance with GPU acceleration and platform-native UI. Cross-platform compatibility meets modern design.
Open Source Alternative to:
Self-hosted AI runtime for text, voice, vision, and agents
Stars
49,628Last commit
7 hours agoLicense
MIT
Run LLMs, speech, image generation, and autonomous agents on your own hardware with an OpenAI-compatible API and 60+ swappable backends.
Open Source Alternative to:
Encrypted note-taking that syncs across all your devices
Stars
56,790Last commit
6 hours agoLicense
Unknown
Cross-platform note-taking app with end-to-end encryption, Markdown support, web clipping, and sync via Dropbox, OneDrive, or Joplin Cloud.
Open Source Alternative to:
Privacy-focused browser with powerful customization
Stars
45,012Last commit
14 hours agoLicense
MPL-2.0
A Firefox-based browser offering enhanced privacy, split views, and extensive customization options for a personalized browsing experience.
Open Source Alternative to:
Lightning-fast analytics for massive datasets
Stars
50,480Last commit
6 hours agoLicense
Apache-2.0
High-performance columnar OLAP database system for real-time analytics on big data, with SQL support and linear scalability.
Open Source Alternative to:
Free database manager for SQL databases and beyond
Stars
52,128Last commit
6 hours agoLicense
Apache-2.0
Cross-platform database management tool for exploring, editing, and querying SQL databases including MySQL, PostgreSQL, SQLite, MariaDB, and more.
Open Source Alternative to:
High-performance vector database for GenAI applications
Stars
46,424Last commit
6 hours agoLicense
Apache-2.0
Open-source vector database optimized for similarity search, scaling to billions of vectors with minimal performance loss
Open Source Alternative to:
Unlock Product Insights with Open-Source Analytics
Stars
40,343Last commit
6 hours agoLicense
MIT
All-in-one product analytics platform. Track user behavior, run experiments, and make data-driven decisions to grow your product.
Open Source Alternative to:
Local AI meeting transcription with zero data leaving your device
Stars
31,916Last commit
1 month agoLicense
MIT
Records, transcribes, and summarizes meetings entirely on your device using local AI. No bots, no cloud uploads, GDPR and HIPAA compliant by design.
Open Source Alternative to:
Open source AI coding agent for the terminal and IDE
Stars
28,571Last commit
6 hours agoLicense
Apache-2.0
Terminal-based AI coding agent that reads your codebase, edits files and runs commands, with support for Qwen, OpenAI, Anthropic, Gemini and local models.
Open Source Alternative to:
Powerful API development and testing made effortless
Stars
40,057Last commit
6 hours agoLicense
Apache-2.0
Intuitive API client for REST, GraphQL, and gRPC. Debug, test, and collaborate on APIs with ease across platforms.
Open Source Alternative to:
AI-powered code completion for seamless development
Stars
33,916Last commit
4 months agoLicense
Apache-2.0
Self-hosted AI coding assistant that enhances productivity with context-aware suggestions and privacy-focused implementation.
Open Source Alternative to:
Blazing-fast in-memory data store for modern applications
Stars
31,796Last commit
6 hours agoLicense
Unknown
Dragonfly is a high-performance, Redis-compatible in-memory data store that delivers up to 25x more throughput and 80% lower costs than legacy solutions.
Open Source Alternative to:
Secure, private photo storage and sharing solution
Stars
29,460Last commit
6 hours agoLicense
AGPL-3.0
End-to-end encrypted cloud storage for photos and videos, offering privacy, security, and seamless cross-device syncing.
Open Source Alternative to:
Private messaging with end-to-end encryption
Stars
29,494Last commit
3 days agoLicense
AGPL-3.0
Secure messaging app with state-of-the-art encryption, voice/video calls, group chats, and file sharing. No ads, trackers, or data collection.
Open Source Alternative to:
Time-series database and historian for industrial data
Stars
25,169Last commit
6 hours agoLicense
AGPL-3.0
High-performance time-series database with industrial data management, built-in stream analytics, and AI-driven anomaly detection for operational environments.
Open Source Alternative to:
Cross-platform, secure password manager
Stars
29,307Last commit
18 hours agoLicense
GPL-3.0
KeePassXC is an open-source password manager that securely stores and manages sensitive information across Windows, macOS, and Linux.
Open Source Alternative to:
Create 2D and 3D games without coding, powered by AI assistance
Stars
27,713Last commit
6 hours agoLicense
Unknown
Free, open-source game engine with visual event system, AI tutor, and one-click publishing to Steam, iOS, Android, and web platforms.
Open Source Alternative to:
Lightning-fast, typo-tolerant search engine for all
Stars
27,003Last commit
6 days agoLicense
GPL-3.0
Open-source search solution offering blazing speed, typo tolerance, and effortless scalability for developers and businesses.
Open Source Alternative to:
Open-source crypto trading bot for market making
Stars
20,574Last commit
4 days agoLicense
Apache-2.0
Automate crypto trading strategies with a powerful, customizable platform. Connect to multiple exchanges and optimize your market making.
Open Source Alternative to:
Full-featured media center for your TV and beyond
Stars
21,347Last commit
6 hours agoLicense
Unknown
Plays videos, music, TV shows, photos, and games from a single interface, with live TV, PVR recording, and broad format support across devices.
Open Source Alternative to:
Self-hosted music streaming for your personal collection
Stars
24,232Last commit
22 hours agoLicense
GPL-3.0
Open source music server that streams your personal library via a web player or any Subsonic-compatible mobile app on iOS and Android.
Open Source Alternative to:
Run dozens of AI coding agents in parallel on your machine
Stars
15,350Last commit
8 hours agoLicense
Elastic-2.0
macOS app that orchestrates multiple AI coding agents simultaneously, each in its own isolated Git worktree, so you can work on many tasks at once.
Open Source Alternative to:
Scalable open-source distributed storage system
Stars
17,138Last commit
6 hours agoLicense
Unknown
Ceph provides unified object, block, and file storage from a single cluster built on commodity hardware.
Open Source Alternative to:
Professional audio editing made simple and free
Stars
18,780Last commit
1 day agoLicense
Unknown
Free, open-source audio editor and recorder for all platforms. Record, edit, mix and enhance audio with professional tools. Perfect for music, podcasts, and more.
Open Source Alternative to:
SQLite-compatible database for scalable multi-tenant applications
Stars
17,279Last commit
2 days agoLicense
MIT
Turso provides a simple developer experience with SQLite compatibility, allowing you to build and scale multi-tenant applications with unlimited databases.
Open Source Alternative to:
Privacy-first offline maps for hiking, cycling & navigation
Stars
15,704Last commit
6 hours agoLicense
Apache-2.0
Free, open-source offline maps app with detailed trails, turn-by-turn navigation, and zero tracking. Perfect for hikers, cyclists, and travelers seeking privacy.
Open Source Alternative to:
Docmost – Open-source wiki software with real-time collaboration, diagrams, AI, SSO, RBAC permissions and more.
Bright Data
InfluxDB
Postiz