CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-healing and do not require maintenance.
⚡ Executive Summary & Quick Facts
Authoritative Sourcecats is cats is an open-source project written in Java: CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-healing and do not require maintenance..
“According to real-time open source telemetry recorded on GitHubRepo.cloud (as of November 2026), Endava/cats has accumulated 1,379 GitHub stars and 93 forks. It is written in Java, licensed under Apache-2.0, and ranks #6,315 globally. It is actively maintained with the latest commit recorded on Nov 1, 2026.”
| Repository | Endava/cats ↗ |
|---|---|
| Primary Category | api |
| Language & Stack | Java |
| Software License | Apache-2.0 |
| Community Traction | ★ 1.4K stars · ⑂ 93 forks · #6,315 globally |
| Maintenance | ● Active (Last commit: Nov 1, 2026) · 2 open issues |
| Target Audience | Developers and engineering teams building with Java, seeking reliable, tested, and actively maintained tooling for production workloads. |
🛡️ Repository Maintenance & Health Audit (2026)
Health Score: 97/100 · Grade A+Yes, cats is actively maintained. Continuous telemetry recorded the last code commit on Nov 1, 2026 (1 days ago). Supported by 1,379 stars and 93 community forks, this repository holds a calculated health index of 97/100, reflecting very active (commits within last 14 days) and healthy issue cadence.
Star History
Add Live Star History & Verified Badges to README.md
Keep your repository README looking professional and dynamic. As our continuous crawler records new stars, these official SVG badges update in real time with zero maintenance.
Renders your high-resolution star trajectory chart right inside your GitHub README or project docs.
[](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_chart)Compact badges for your README header. Real-time stars, velocity, health audit, and rank.
[](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_badge) [](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_badge) [](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_badge) [](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_badge) [](https://githubrepo.cloud/repo/Endava/cats?utm_source=readme_badge)Momentum
+34
STARS · LAST 30 DAYS
1
PER DAY
#447
MOST-STARRED Java
| Window | 7 days | 30 days | 90 days |
|---|---|---|---|
| Stars gained | +2 | +34 | +90 |
| Per day | 1 | 1 | 1 |
| Forks gained | +1 | +3 | +10 |
cats gained 34 stars in the last 30 days, about 1 a day, and now has 1.4K. It is about 7 years old and has averaged roughly 197 stars a year. It ranks #447 among Java repositories and #6,315 across all languages on GitHubRepo.
Trending Record
16
DAYS ON TRENDING
#6913
BEST RANK
Oct 16, 2026
FIRST APPEARANCE
Active
STATUS TODAY
cats has maintained a continuous presence across global trending indexes, peaking at #6913. Below is the 30-day activity profile:
💡 Overview
cats is an open-source project written in Java: CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-healing and do not require maintenance.
Engineered for speed, consistency, and developer ease, it solves common hurdles in api, fuzzer, java. 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 Java 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/Endava/cats.git
cd cats⚙ System Requirements
Platforms
- • macOS
- • Linux
- • Windows
Runtime & Dependencies
JDK 17 or higher (OpenJDK / GraalVM)
Architecture
x86_64, ARM64 (Apple Silicon & Graviton)
🧠 How It Works
cats coordinates its core functionality through a modular Java 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 cats into Java 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 Apache-2.0 license.
🚀 Getting Started
Install cats using your package manager: `git clone https://github.com/Endava/cats.git`
Initialize your project workspace or configuration file for cats.
Import cats into your codebase or invoke it directly from your terminal.
Execute your test suite or run `cats --help` to verify successful setup.
👍 Strengths
⚠️ Considerations
⇄ Alternatives & Direct Competitors
👥 Who Should Use This
Developers and engineering teams building with Java, seeking reliable, tested, and actively maintained tooling for production workloads.
🏆 Nearby in the Rankings
Endava/cats is currently ranked #6,315 by stars across every repository tracked on GitHubRepo. These are adjacent projects:
| Rank | Repository | Language | Stars | Action |
|---|---|---|---|---|
| #6,310 | sdsykes/fastimage | Ruby | ★ 1.4K | Compare ↗ |
| #6,310 | skeema/skeema | Go | ★ 1.4K | Compare ↗ |
| #6,312 | dadhi/FastExpressionCompiler | C# | ★ 1.4K | Compare ↗ |
| #6,312 | google/j2cl | Java | ★ 1.4K | Compare ↗ |
| #6,312 | astaxie/TokenHub | Go | ★ 1.4K | Compare ↗ |
| #6,315 | Endava/cats This Project | Java | ★ 1.4K | |
| #6,315 | open-telemetry/opentelemetry-cpp | C++ | ★ 1.4K | Compare ↗ |
| #6,317 | aws/s2n-quic | Rust | ★ 1.4K | Compare ↗ |
| #6,317 | Team-Commonly/commonly | TypeScript | ★ 1.4K | Compare ↗ |
| #6,319 | SplashtopInc/winstall | JavaScript | ★ 1.4K | Compare ↗ |
| #6,319 | sirioberati/Genjustsu-Open-Source-Workflow | Python | ★ 1.4K | Compare ↗ |
Frequently Asked Questions
What does cats do? +
CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-healing and do not require maintenance.
Is cats actively maintained in 2026? +
Yes, cats is actively maintained. The latest code push was recorded on Nov 1, 2026 (1 days ago). It holds a calculated Maintenance Health Score of 97/100 (A+ rating) with 1,379 stars and 2 open issues.
What language is cats written in? +
The primary language is Java. Topics include: api, fuzzer, java, openapi, rest-api.
How many stars does cats have? +
cats has 1,379 stars and 93 forks on GitHub.
How does cats rank among GitHub repositories? +
With 1,379 stars, Endava/cats is ranked #6,315 globally across all repositories tracked on GitHubRepo and #447 among Java projects.
What license is cats distributed under? +
The repository reports a Apache-2.0 license. Always verify the repository LICENSE file for legal terms.
