🧑‍⚖️ Judge0 Installation Guide (v1.13.1)

📌 Introduction

Judge0 is a robust, scalable, open-source code execution platform used to build:

• Competitive programming systems
• Online IDEs
• Online code editors
• Programming assessments
• Automated grading systems

It supports 60+ programming languages.

We will install Judge0 v1.13.1 locally.

🖥️ System Requirements

• Officially supported on Linux
• Can be installed on:
  • Windows (via WSL)
  • Linux (native)

⚠️ No official native Windows support without WSL.

✅ Prerequisites

• Laptop/Desktop (Windows or Linux)
• Stable internet connection

🪟 Windows Installation (Using WSL)

🔹 Enable WSL & Virtual Machine Platform

1. Press Win + R

2. Type: optionalfeatures.exe

3. Enable:

   • ✅ Virtual Machine Platform
   • ✅ Windows Subsystem for Linux

4. Restart your system

🔹 Install WSL

Open PowerShell:

bash
wsl.exe --install
wsl.exe --install

Check installation:

bash
wsl -v
wsl -v

Install Ubuntu:

bash
wsl --install
wsl --install

Run Ubuntu:

bash
wsl -d Ubuntu
wsl -d Ubuntu

🐧 Ubuntu (Linux Configuration)

Edit GRUB:

bash
sudo nano /etc/default/grub
sudo nano /etc/default/grub

Add inside:

bash
GRUB_CMDLINE_LINUX="systemd.unified_cgroup_hierarchy=0"
GRUB_CMDLINE_LINUX="systemd.unified_cgroup_hierarchy=0"

Apply changes:

bash
sudo update-grub
sudo reboot
sudo update-grub
sudo reboot

🐳 Common Installation Steps (Linux / WSL)

🔹 Step 1: Update System

bash
sudo apt update -y && sudo apt upgrade -y
sudo apt update -y && sudo apt upgrade -y

🔹 Step 2: Install Docker & Docker Compose

bash
sudo apt install docker.io
sudo apt install docker-compose-v2
sudo apt install docker.io
sudo apt install docker-compose-v2

🔹 Step 3: Install unzip

bash
sudo apt install unzip
sudo apt install unzip

🔹 Step 4: Download Judge0 v1.13.1

bash
wget https://github.com/judge0/judge0/releases/download/v1.13.1/judge0-v1.13.1.zip
wget https://github.com/judge0/judge0/releases/download/v1.13.1/judge0-v1.13.1.zip

🔹 Step 5: Extract Files

bash
unzip judge0-v1.13.1.zip
cd judge0-v1.13.1
unzip judge0-v1.13.1.zip
cd judge0-v1.13.1

🔹 Step 6: Configure Passwords

Edit:

bash
nano judge0.conf
nano judge0.conf

Update:

REDIS_PASSWORD=YourPassword
POSTGRES_PASSWORD=YourPassword

⚠️ Do NOT modify docker-compose.yml unless you know what you're doing.

🔹 Step 7: Start Redis & Postgres

bash
docker-compose up -d db redis
docker-compose up -d db redis

Wait for initialization.

🔹 Step 8: Start Judge0

bash
docker-compose up -d
docker-compose up -d

After successful startup:

http://localhost:2358

White page is normal.

🧪 Testing Installation

Visit:

http://localhost:2358/dummy-client.html

If you get Accepted, installation is successful.

❗ Fixing Error

Error:

No such file or directory @ rb_sysopen - /box/script.js

🔍 Check Cgroup Version

bash
stat -fc %T /sys/fs/cgroup
stat -fc %T /sys/fs/cgroup

Output Meaning:

• cgroup2fs → Cgroup v2
• tmpfs or cgroup → Cgroup v1

Judge0 may require Cgroup v1.

🔧 Downgrade Docker to Cgroup v1

Step 1: Open settings file

Windows

C:\Users\[Username]\AppData\Roaming\Docker\settings-store.json

Mac

~/Library/Group Containers/group.com.docker/settings-store.json

Linux

~/.docker/desktop/settings-store.json

Step 2: Add

json
{
  "DeprecatedCgroupv1": true
}
{
  "DeprecatedCgroupv1": true
}

Restart Docker.

🪟 Windows WSL + Docker Desktop Integration

1. Docker → Settings → General ✅ Enable “Use the WSL 2 based engine”

2. Settings → Resources → WSL Integration ✅ Enable Ubuntu

▶️ Re-run Judge0

bash
docker-compose up -d
docker-compose up -d

⛔ Stop Judge0

bash
docker-compose down
docker-compose down

📚 Useful Links

• /dummy-client.html
• /languages
• /docs

📖 References

• Judge0 Official Documentation
• GitHub Judge0 Repository

💡 Suggestions

• Reinstall cleanly if errors persist
• Avoid multiple release downloads
• Reinstall Docker if architecture conflicts occur
• If unresolved, consider RapidAPI or alternative hosting

🎯 Final Note

If it runs at:

http://localhost:2358

Then your Judge0 instance is successfully installed 🚀