Luis Goés — Software EngineerEngineering the parts you don't see.

Backend engineer specialised in Java and Spring Boot. I design APIs, data models and integrations — and build AI into them so it does real work, not demos.

See the work Start a conversation

Focus: Backend · APIs · AI integration
Core: Java · Spring Boot
Now: A Spring Boot platform in production
Open to: Roles & freelance projects

Scroll to assemble the system

How I build

Every system is assembled layer by layer.

Six areas of work, in the order a system comes together. Scroll and the model on the right is built along with them.

01 / 06System Architecture

Structure before code.

I start with boundaries: modules that can't reach into each other, layers with one job, and a data model shaped by the questions it has to answer.

Problems I solve

Monoliths that became hard to change
Unclear ownership between modules
Schemas that fight the queries

Spring Modulith
DDD layering
PostgreSQL
Flyway

02 / 06Backend Engineering

Java and Spring Boot at the core.

Transactions, concurrency, scheduled jobs and security are where systems usually break. This is the work I specialise in, with Java and the Spring ecosystem.

Problems I solve

Race conditions and duplicate processing
Slow queries and N+1 access
Permissions hard-coded instead of configurable

Java
Spring Boot
Spring Security
Spring Data JPA
Hibernate

03 / 06API Development

Contracts other people can rely on.

GraphQL and REST APIs with explicit schemas, pagination that scales, batched resolvers and limits that protect the service.

Problems I solve

Frontends blocked by unstable contracts
Over-fetching and chatty clients
Public endpoints without rate limits

GraphQL
REST
OpenAPI
Redis

04 / 06AI Integration

AI that works inside the system.

Agents that call real tools under the user's own permissions, retrieval over company knowledge, validated structured outputs, and cost tracked on every call.

Problems I solve

LLM features that can't touch real data safely
Answers without grounding
Unpredictable AI spend

Spring AI
LangChain4j
LangChain
RAG
MCP

05 / 06Automation & Integrations

Systems that talk to each other reliably.

Webhook inboxes that never drop an event, rate-limited syncs with third-party APIs, and scripts that change hundreds of production flows with a dry run and a rollback.

Problems I solve

Lost or duplicated webhooks
429 storms from external APIs
Manual, error-prone operations

Python
Node.js
Webhooks
HMAC

06 / 06Full Stack Development

And the interface on top.

When the job needs it, I build the frontend too — typed API clients, real-time updates and accessible components — in Angular, React or Next.js.

Problems I solve

Backends nobody can operate
Screens that drift from the API
Interfaces that flicker and jump

Angular
React
Next.js
TypeScript

06 / 06 · Assembled

One system, every layer.

Architecture, backend, APIs, AI, integrations and interface are one piece of work. This is where it has been put to use.

Selected work

What it looks like in production.

01Featured · Backend & full stack · In production

Agency Operations Platform

A management platform that replaces a scattered set of SaaS tools and a legacy system: sales from three checkout platforms, a CRM mirror, WhatsApp, HR and a unified customer base — with AI agents that work on the same data and permissions.

20: Spring Modulith modules, boundaries enforced by tests
≈420: GraphQL queries and mutations
1,330+: backend tests on real PostgreSQL and Redis
45 s → 18 ms: dashboard query after profiling

Read case study

All work

Have a system to build — or to fix?

I'm open to full-time roles and freelance projects.

Get in touch