Open Source Projects using C++
A curated collection of the 70 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
178,973Last commit
8 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:
Run LLMs locally with minimal setup, maximum hardware support
Stars
124,707Last commit
7 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
121,254Last commit
17 hours 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
111,725Last 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:
Free 2D and 3D game engine for cross-platform projects
Stars
115,878Last commit
7 hours 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
88,731Last commit
22 hours 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
77,843Last 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
75,732Last commit
8 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:
An independent browser engine built from scratch, not a fork
Stars
65,743Last commit
7 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:
Real-time monitoring for systems and applications
Stars
80,229Last commit
8 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:
Free, open-source software for video recording and live streaming
Stars
75,212Last commit
5 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:
Run open-source AI models privately on your own device
Stars
77,404Last 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
59,890Last commit
8 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
48,580Last commit
8 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
56,009Last commit
10 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:
Lightning-fast analytics for massive datasets
Stars
49,340Last 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:
Privacy-focused browser with powerful customization
Stars
43,980Last commit
7 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:
Free database manager for SQL databases and beyond
Stars
51,476Last 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
45,698Last commit
8 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
37,777Last 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:
Powerful API development and testing made effortless
Stars
39,956Last commit
8 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:
Local AI meeting transcription with zero data leaving your device
Stars
29,520Last commit
3 months 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:
AI-powered code completion for seamless development
Stars
33,829Last commit
2 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
31,012Last 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
28,417Last commit
9 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
29,222Last commit
2 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
25,068Last commit
4 days 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
28,453Last commit
7 days agoLicense
Unknown
KeePassXC is an open-source password manager that securely stores and manages sensitive information across Windows, macOS, and Linux.
Open Source Alternative to:
Lightning-fast, typo-tolerant search engine for all
Stars
26,452Last commit
2 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:
Create 2D and 3D games without coding, powered by AI assistance
Stars
25,786Last 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:
Open-source crypto trading bot for market making
Stars
19,507Last commit
9 hours 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:
Self-hosted music streaming for your personal collection
Stars
22,969Last commit
7 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:
Scalable open-source distributed storage system
Stars
16,948Last commit
7 hours agoLicense
Unknown
Ceph provides unified object, block, and file storage from a single cluster built on commodity hardware.
Open Source Alternative to:
Run dozens of AI coding agents in parallel on your machine
Stars
13,088Last commit
6 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:
SQLite-compatible database for scalable multi-tenant applications
Stars
17,147Last commit
8 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:
Professional audio editing made simple and free
Stars
17,603Last commit
11 hours 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:
High-performance time-series database for massive data scale
Stars
17,264Last commit
7 hours agoLicense
Apache-2.0
Open-source time-series database offering massive ingestion throughput, millisecond queries, and SQL extensions, designed for optimal performance at any hardware scale.
Open Source Alternative to:
Privacy-first offline maps for hiking, cycling & navigation
Stars
15,152Last commit
7 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:
Advanced terminal with modern features for Mac developers
Stars
17,944Last commit
17 hours agoLicense
GPL-2.0
Feature-rich terminal replacement for macOS with split panes, search, autocomplete, and extensive customization options for enhanced productivity.
Open Source Alternative to:
Free, open-source framework for cross-platform game development
Stars
14,321Last commit
8 hours agoLicense
Unknown
Build games in C# that run on Windows, macOS, Linux, iOS, Android, and major consoles. No royalties, no subscriptions, no runtime fees.
Open Source Alternative to:
Self-hosted file sync with AI-powered organization
Stars
15,146Last commit
12 days agoLicense
Unknown
Open source file sync and sharing platform with custom properties, AI automation, collaborative editing, and enterprise-grade security for teams.
Open Source Alternative to:
A free, open source, cross-platform video editor
Stars
14,943Last commit
16 hours agoLicense
GPL-3.0
Free, open-source video editor supporting 4K resolution, hundreds of formats, and professional features like Blackmagic Design integration across Windows, Mac, and Linux.
Open Source Alternative to:
Capture – Capture screenshots, generate PDFs, scrape content, extract metadata, and automate browsers with one API.
Openlane
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CodeRabbit