// Hi, I'm Nelson
I'm a backend developer in training based in Spain. I'm doing a vocational degree in Software Development (DAM — a 2-year technical program focused on software engineering) and before that I did one in IT Systems & Networking (SMR — networks, servers, and operating systems from scratch).
The networking and systems background was unplanned but it stuck — it gives me context that I find useful when working on backend.
Java and Spring Boot is where I spend most of my time — REST APIs, layered architecture, security, persistence. Real projects I actually deploy and use, not just tutorials I followed once and forgot.
On the side I'm learning Rust. Not because it's practical right now, but because it's genuinely fascinating — the way it thinks about memory and ownership is unlike anything else I've touched. It's the kind of challenge I enjoy.
I'm determined, consistent, and I know what I want: to make a living doing something that challenges me constantly. That's what this is about.
Outside of code — books, anime, gaming, training and learning things I definitely don't need yet.
see my projects
FitTrack
wip
Fitness and nutrition REST API with AI-powered technique analysis and food identification via Gemini API. Built with Petter5-5 ↗.
savings-api
complete
Multi-user personal savings app. JWT auth, savings goals, transaction history and automatic email notifications.
JuegoRPG
complete
Turn-based RPG with Swing GUI. Strategy Pattern for combat, Template Method across character types.
Next project
—
Something is being built.
Next project
—
Something is being built.
Languages
Java 21
Rust
SQL
Backend
Spring Boot
Spring Security
JPA / Hibernate
MySQL
PostgreSQL
SQL Server
Maven
Swagger
JUnit 5
REST APIs
Infra & DevOps
Docker
Linux VPS
AWS EC2/S3/VPC
Nginx
Apache
Debian Server
Ubuntu Server
SSH
Networking and Systems SMR
TCP/IP
DNS
DHCP
Cisco Packet Tracer
Windows Server
Active Directory
LAN/WAN
Routing and Switching
Virtualization
Assembly and Hardware
Tools
Git
GitHub
IntelliJ
Postman
VS Code
SSMS
Open to backend opportunities in Spain or remote — available now.
nelson@nelsonffkarlsson.com
copy ↗
github.com/NUXX-G
↗
linkedin · Nelson Filipe Fardilha Karlsson
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