Open Source Projects using C++
A curated collection of the 71 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
180,472Last commit
12 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
127,518Last commit
11 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
122,939Last commit
16 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
113,660Last commit
12 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
116,830Last commit
14 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
90,376Last commit
9 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
77,902Last commit
11 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
76,453Last 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
66,102Last commit
11 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
75,975Last commit
4 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
80,467Last commit
12 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
77,382Last 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
60,853Last commit
14 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
48,985Last commit
15 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
56,282Last commit
12 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
49,741Last commit
11 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
44,346Last commit
13 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
51,698Last commit
12 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
46,026Last commit
17 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
39,673Last commit
11 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
30,512Last commit
14 hours 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:
Powerful API development and testing made effortless
Stars
39,999Last commit
14 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
33,871Last 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
31,457Last commit
15 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
28,728Last commit
14 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
29,311Last commit
16 hours 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
25,102Last commit
23 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
28,722Last commit
2 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:
Create 2D and 3D games without coding, powered by AI assistance
Stars
26,346Last commit
15 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
26,531Last commit
8 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
19,920Last commit
2 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:
Self-hosted music streaming for your personal collection
Stars
23,402Last commit
21 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
13,940Last commit
11 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
17,015Last commit
13 hours agoLicense
Unknown
Ceph provides unified object, block, and file storage from a single cluster built on commodity hardware.
Open Source Alternative to:
SQLite-compatible database for scalable multi-tenant applications
Stars
17,209Last commit
13 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
18,359Last commit
17 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:
Privacy-first offline maps for hiking, cycling & navigation
Stars
15,350Last commit
11 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:
High-performance time-series database for massive data scale
Stars
17,311Last commit
13 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:
Advanced terminal with modern features for Mac developers
Stars
18,027Last commit
13 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
14,401Last commit
4 days 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
15,222Last 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
15,109Last commit
12 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:
Stellar Hosted – Managed Open Source software hosting in the EU: secure, compliant, fast.
InfluxDB
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