Midas Core – JPMorgan Chase Software Engineering Simulation (Forage)

This repository contains my implementation of Midas Core, developed as part of the JPMorgan Chase & Co. Advanced Software Engineering Virtual Experience Program on Forage.

The project simulates a real-world, production-style backend system responsible for ingesting, validating, processing, and exposing financial transaction data using modern backend technologies.

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🧠 Project Overview

Midas Core is a Spring Boot–based microservice that:

• Consumes high-volume transaction messages from Apache Kafka
• Validates and persists transactions using Spring Data JPA
• Maintains user balances in a relational database
• Integrates with an external Incentive REST API
• Exposes a REST endpoint for querying user balances
• Is fully verified through automated and debugger-driven test suites

The system follows an event-driven architecture and demonstrates service-to-service communication, persistence, and API design.

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🛠️ Tech Stack

• Java 17
• Spring Boot
• Apache Kafka
• Spring Data JPA
• H2 In-Memory Database
• REST APIs (RestTemplate)
• Maven
• JUnit & Embedded Kafka for testing

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📌 Features Implemented (Task Breakdown)

Task 1 – Project Setup

• Configured Spring Boot project with required dependencies
• Verified build and test environment using Maven

Task 2 – Kafka Integration

• Implemented a Kafka listener to consume transactions from a configurable topic
• Used embedded Kafka for test-driven validation
• Deserialized messages into domain-level Transaction objects

Task 3 – Validation & Persistence

• Modeled relational entities using JPA
• Validated transactions based on user existence and balance constraints
• Persisted valid transactions and updated sender/recipient balances
• Discarded invalid transactions without modifying state

Task 4 – Incentive API Integration

• Integrated an external REST-based Incentive API
• Posted validated transactions and processed incentive responses
• Applied incentives only to recipients (not senders)
• Persisted incentive amounts alongside transaction records

Task 5 – REST API Exposure

• Implemented a Spring REST controller exposing GET /balance
• Returned JSON-serialized balance responses
• Defaulted balance to 0 for non-existent users
• Configured application to run on port 33400

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🌐 API Endpoint

Get User Balance

http://localhost:33400/balance?userId=

Example Response

{
  "balance": 1234.56
}

🔗 Simulation Reference

JPMorgan Chase & Co. – Advanced Software Engineering Virtual Experience https://www.theforage.com/simulations/jpmorgan/advanced-software-engineering-r0fm