⚡ Now supporting C++, Java, and Python

JudgeLib

Plug-n-Play Code Execution Engine

Execute code safely and efficiently with built-in queue management and resource limits. Ideal for coding platforms, education tools, and automated test systems.

Performance Overview

Self-hosted, Docker-isolated, and KEDA-powered — JudgeLib delivers reliable, scalable code execution across distributed workers.

Supported Languages (Python, C++, Java)

∞

Scalable Executions (Limited by Cluster Resources)

~0.8s – 2.5s

Avg Execution Time (varies by pods & language)

99.9%

Uptime (Self-Hosted with KEDA Auto-scaling)

*Metrics are approximate and depend on active pods, system load, and test case complexity in the Kubernetes cluster.

Choose Your Integration

Pick the setup that fits your infrastructure best

NPM Library

Integrate JudgeLib directly into your Node.js app

Divides testcases and dumps them into Redis queues
Executes securely via Node.js child process isolation
Perfect for local or small-scale setups

Microservice (Render)

Serverless worker-based setup with REST APIs

3 free Render workers for parallel execution
Requires regular pinging to stay active
Limited resources, slower response, moderate security
Uses Node.js spawn for isolated runs

Self-Host (Docker + KEDA)

Run JudgeLib in your own secure cloud environment

Full Docker isolation for better security
Uses KEDA + HPA for automatic pod scaling
Production-grade performance and reliability
Ideal for enterprises and heavy workloads

Powerful Features

Everything you need for safe and efficient code execution

Real-Time Execution

Execute and stream results instantly with built-in timeout and sandbox handling.

Redis-Based Queueing

Efficient job management and worker load balancing for high concurrency.

Secure Execution

Isolated environment ensures code safety and prevents system-level access.

Ready to Get Started?

Join hundreds of developers using JudgeLib for safe code execution