From Scaffolding to Debugging: Spring Boot with GitHub Copilot CLI

Anupam Kushwaha — Mon, 09 Feb 2026 18:33:58 +0000

This is a submission for the GitHub Copilot CLI Challenge

What I Built

I built a production-ready Spring Boot REST API secured with JWT authentication.

The application includes:

User registration and authentication
Stateless JWT-based authorization
Task management (CRUD operations)
Layered architecture (controller, service, repository, entity, DTO)
Multi-database support:
- H2 for local development
- PostgreSQL for production readiness

This project explores whether GitHub Copilot CLI can act as a real engineering assistant — not just a code generator — while building a secure backend following real-world Spring Boot best practices.

Demo

🔗 Repository:

https://github.com/anupamkushwaha85/copilot-cli-springboot-jwt

Screenshots

Project scaffolding with GitHub Copilot CLI

JWT security and service layer generation

Debugging Spring Security (403 Forbidden issue)

API testing with Postman

Protected endpoints in action

My Experience with GitHub Copilot CLI

GitHub Copilot CLI was used throughout the entire development lifecycle — not just for initial scaffolding.

Copilot CLI assisted with:

Generating the complete project structure and Maven configuration
Creating entities, repositories, services, controllers, and DTOs
Implementing JWT authentication and Spring Security configuration
Adapting the application for H2 (development) and PostgreSQL (production)
Generating documentation alongside the code

Real Debugging with Copilot CLI

One of the most valuable moments was debugging a 403 Forbidden error on the authentication endpoints.

Instead of trial-and-error:

Copilot CLI analyzed the Spring Security configuration
Identified default form login and HTTP basic auth interference
Suggested disabling them explicitly
Provided the exact fix in SecurityConfig

This experience showed that Copilot CLI is effective not only for writing code, but also for systematic debugging and root-cause analysis. It significantly reduced setup friction and allowed me to focus on architecture and correctness instead of boilerplate.

Outcome:

A production-ready backend built end-to-end with GitHub Copilot CLI, demonstrating real-world usage beyond code generation.