OpenExecutor

A sandboxed code execution engine for HackStack — built with Spring Boot.

What it does

1. Consumes code execution requests from Kafka (code-executor topic)
2. Loads test cases from Redis (populated from hackstack-problems at startup)
3. Compiles and runs code in isolated sandboxes using isolate
4. Measures runtime and memory per test case
5. Publishes results to Kafka (code-results topic)

Tech Stack

• Java 17
• Spring Boot 3.5
• Apache Kafka (consumer + producer)
• Redis (test case caching)
• isolate (sandbox execution)
• Maven

Getting Started

Prerequisites

• Java 17+
• Redis running on localhost:6379
• Kafka running on localhost:9092
• isolate installed (for sandboxed execution)
• hackstack-problems cloned as a sibling directory

Run

# Build
./mvnw clean package

# Run
./mvnw spring-boot:run

# Run tests
./mvnw test

The service starts on port 8081.

Configuration

All configuration is in src/main/resources/application.properties:

Property	Default	Description
server.port	8081	Server port
spring.data.redis.host	localhost	Redis host
spring.data.redis.port	6379	Redis port
spring.kafka.bootstrap-servers	localhost:9092	Kafka broker
basePath	../hackstack-problems	Path to problems directory

Supported Languages

• Java
• JavaScript

Related Repositories

• HackStack — Parent repository
• HackStack-monorepo — Web frontend, backend API, webhook
• hackstack-problems — Problem definitions and test cases