Optimized primitives for collective multi-GPU communication
⚡ Executive Summary & Quick Facts
Authoritative Sourcenccl is nccl is an open-source project written in C++: Optimized primitives for collective multi-GPU communication..
“According to real-time open source telemetry recorded on GitHubRepo.cloud (as of November 2026), NVIDIA/nccl has accumulated 5,142 GitHub stars and 1,434 forks. It is written in C++, licensed under NOASSERTION, and ranks #2,613 globally. It is actively maintained with the latest commit recorded on Oct 7, 2026.”
| Repository | NVIDIA/nccl ↗ |
|---|---|
| Primary Category | communications |
| Language & Stack | C++ |
| Software License | NOASSERTION |
| Community Traction | ★ 5.1K stars · ⑂ 1.4K forks · #2,613 globally |
| Maintenance | ● Active (Last commit: Oct 7, 2026) · 446 open issues |
| Target Audience | Developers and engineering teams building with C++, seeking reliable, tested, and actively maintained tooling for production workloads. |
🛡️ Repository Maintenance & Health Audit (2026)
Health Score: 85/100 · Grade AYes, nccl is actively maintained. Continuous telemetry recorded the last code commit on Oct 7, 2026 (25 days ago). Supported by 5,142 stars and 1,434 community forks, this repository holds a calculated health index of 85/100, reflecting regular maintenance (25 days ago) and active community feedback (446 open).
Star History
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+129
STARS · LAST 30 DAYS
4
PER DAY
#182
MOST-STARRED C++
| Window | 7 days | 30 days | 90 days |
|---|---|---|---|
| Stars gained | +0 | +129 | +360 |
| Per day | 1 | 4 | 4 |
| Forks gained | +0 | +29 | +72 |
nccl gained 129 stars in the last 30 days, about 4 a day, and now has 5.1K. It is about 11 years old and has averaged roughly 467 stars a year. It ranks #182 among C++ repositories and #2,613 across all languages on GitHubRepo.
Trending Record
68
DAYS ON TRENDING
#100
BEST RANK
Nov 14, 2015
FIRST APPEARANCE
Active
STATUS TODAY
nccl has maintained a continuous presence across global trending indexes, peaking at #100. Below is the 30-day activity profile:
💡 Overview
nccl is an open-source project written in C++: Optimized primitives for collective multi-GPU communication.
Engineered for speed, consistency, and developer ease, it solves common hurdles in communications, cpp, cuda. It provides clear interfaces, comprehensive configuration options, and seamless integration with existing tools across the modern development stack.
⚡ Key Features
Optimized execution pipeline written in C++ for predictable speed.
Zero-friction configuration with comprehensive sensible defaults out of the box.
Cross-platform runtime support across Linux, macOS, and Windows environments.
Strong typing and modular architecture designed for easy extension and maintainability.
Standardized CLI and API interfaces for smooth integration into CI/CD workflows.
Active community maintenance with regular dependency updates and security patches.
📥 Installation
$ git clone https://github.com/NVIDIA/nccl.git
cd nccl⚙ System Requirements
Platforms
- • macOS
- • Linux
- • Windows
Runtime & Dependencies
C++20 compliant compiler (GCC 11+, Clang 13+, MSVC)
Architecture
x86_64, ARM64 (Apple Silicon & Graviton)
🧠 How It Works
nccl coordinates its core functionality through a modular C++ pipeline. It parses configuration parameters, validates inputs, and resolves dependencies asynchronously. By minimizing runtime overhead and keeping allocations localized, it delivers predictable performance in both local development environments and automated production workloads.
🎯 Production Use Cases
Production System Integration
Embed nccl into C++ backend services to handle core application logic.
CI/CD Automated Pipelines
Run automated validation, builds, and integration suites during deployments.
Developer Tooling & Workflows
Accelerate developer onboarding with pre-configured project utilities.
Open Source Extension
Fork and customize internal modules under the repository's open NOASSERTION license.
🚀 Getting Started
Install nccl using your package manager: `git clone https://github.com/NVIDIA/nccl.git`
Initialize your project workspace or configuration file for nccl.
Import nccl into your codebase or invoke it directly from your terminal.
Execute your test suite or run `nccl --help` to verify successful setup.
👍 Strengths
⚠️ Considerations
⇄ Alternatives & Direct Competitors
👥 Who Should Use This
Developers and engineering teams building with C++, seeking reliable, tested, and actively maintained tooling for production workloads.
🏆 Nearby in the Rankings
NVIDIA/nccl is currently ranked #2,613 by stars across every repository tracked on GitHubRepo. These are adjacent projects:
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|---|---|---|---|---|
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| #2,613 | NVIDIA/nccl This Project | C++ | ★ 5.1K | |
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Frequently Asked Questions
What does nccl do? +
Optimized primitives for collective multi-GPU communication
Is nccl actively maintained in 2026? +
Yes, nccl is actively maintained. The latest code push was recorded on Oct 7, 2026 (25 days ago). It holds a calculated Maintenance Health Score of 85/100 (A rating) with 5,142 stars and 446 open issues.
What language is nccl written in? +
The primary language is C++. Topics include: communications, cpp, cuda, deep-learning, gpu.
How many stars does nccl have? +
nccl has 5,142 stars and 1,434 forks on GitHub.
How does nccl rank among GitHub repositories? +
With 5,142 stars, NVIDIA/nccl is ranked #2,613 globally across all repositories tracked on GitHubRepo and #182 among C++ projects.
What license is nccl distributed under? +
The repository reports a NOASSERTION license. Always verify the repository LICENSE file for legal terms.
