Rui Martins — Software Engineer

From rendering
worlds to
routing data.

[ 01 — profile ]

I spent my first years shipping VR rehab tools and educational games in Unity. Then I went deep into the backend — and found the same craft in resilient microservices that refuse to drop a message.

Today I design and own .NET services inside large-scale, event-driven architectures — the kind with dozens of APIs, Kafka pipelines, retry topics, dead-letter queues and a Redis layer that has to be fast and never lie.

I lead backend teams, shape architecture, and care as much about a 0.3-second response as I once did about 60 frames per second.

Backend Tech LeadEvent-Driven Systems API PerformanceResilience & Retries AZ-900 Certified

The pipeline.

[ 02 — experience · 2020 → now ]

2020 — 2021

HEI-Lab

Software Developer/Mar 2020 — May 2021/Lisbon

Multiple projects Mar 2020 — May 2021

Built VR cognitive-rehabilitation experiences in Unity, including tooling to capture and analyze biometric signals for behavioral research.
Developed a .NET MVC web app exposing APIs to store, retrieve and download biometric datasets.

UnityC#.NET MVCBiometrics

2021 — 2022

Easylab

Software Developer/Jan 2021 — Dec 2022/Lisbon

Multiple projects Jan 2021 — Dec 2022

Created gamified educational experiences in Unity — browser-based games and an interactive book application.
Shipped a cross-platform interactive book in C# targeting Android, iOS and Web.
Integrated backend APIs to persist user progress, scores and app data.

UnityC#Cross-PlatformREST APIs

2023 — 2025

Capgemini

Software Engineer/Mar 2023 — Dec 2023/Lisbon

Lead Software Engineer/Jan 2024 — Mar 2025/Lisbon

REN (Redes Energéticas Nacionais) Mar 2023 — Mar 2025

Optimized a critical aggregation endpoint from ~16s to ~0.3s across thousands of records.
Designed .NET APIs serving large datasets for responsive, user-driven data manipulation in a JS frontend.
Led frontend efforts and improved complex data visualizations.
Refactored core components for performance, scalability and maintainability.
Defined coding standards, led code reviews, coordinated sprint planning within Scrum.

.NET 6+API PerfJS / ReactScrum Lead

2025 — now

Babel

● Current position

Senior Software Engineer/Mar 2025 — Present/Lisbon

IRN (Instituto dos Registos e do Notariado) Mar 2025 — May 2026

Built & maintained dozens of .NET APIs in a large-scale, event-driven microservices architecture.
Owned resilient Kafka background jobs — retry strategies, retry topics and dead-letter queues.
Designed and optimized production database queries for performance, scalability and reliability.
Authored shared NuGet packages, including common libraries and a resilient Redis access layer.
Built React components and forms that integrate with the platform's APIs.
Acted as backend tech lead and stepped into cross-team architecture decisions.

.NET 8ReactKafkaRedisNuGetMicroservices

GRA (Governo Regional dos Açores) May 2026 — Present

Act as solution architect & tech lead, hands-on across backend and frontend.
Defined the full stack — .NET 10, React, PostgreSQL — and designed the solution on client-provisioned VMs.
Built a high-availability database layer: 2 PostgreSQL nodes across 3 VMs, with etcd + Patroni replicating data automatically and handling failover.

.NET 10ReactPostgreSQLPatronietcdHigh Availability

signature optimization

One endpoint.
53× faster.

A critical .NET endpoint aggregating data across multiple tables — re-architected to collapse a 16-second wait into a fraction of a second for thousands of records.

BEFORE — response time0.0

AFTER — re-architected0.0

0 faster · ~98% latency removed

signature refactor

One table.
60% less code.

A planning table streaming thousands of hourly records — dozens of interactions, in-place edits, saved versions. Rewritten from ~5,000 lines down to ~2,000 while backend queries got 5× faster and editing went from laggy to smooth.

BEFORE — frontend code0.0

AFTER — refactored0.0

0 faster backend · zero lag on the frontend

The stack.

[ 03 — capabilities ]

be

Backend

C#
.NET Core / 6+
ASP.NET Core
Microservices
Monolithic
Event-Driven
Kafka

db

Data

PostgreSQL
OracleDB
SQL Server
MySQL
Redis
Patroni
etcd

fe

Frontend

JavaScript
TypeScript
React
HTML5
CSS
jQuery

ops

DevOps & Craft

Docker
Docker Compose
CI/CD
GitHub Actions
High Availability
Git
Agile / Scrum
Unity

Education

BSc Game Development

Universidade Lusófona · 2017–2020

Programming

ESSJT, São João da Talha · 2011–2013

Certifications

Azure Fundamentals

Microsoft · AZ-900

Languages

Portuguese C2

English C1

Spanish A2

From renderingworlds torouting data.