FINANCIAL SOFTWARE & INTEGRATIONS
Wealth Hub
A personal portfolio app that brings together data from different financial platforms and shows my wealth, allocation and performance over time.
Founder & Lead Developer
Read the case study THIJS STEKELENBURG / SOFTWARE DEVELOPER
Software that makes
life easier .
I build backends, apps and integrations that turn complex data into useful software.
Software Development student. Independent developer behind Stekelcode.
FROM IDEA TO IMPLEMENTATIONBackends & APIsWeb & Flutter appsData & automation
Python / FastAPI / Flutter / PostgreSQLExplore the work
SELECTED WORK
Built to solve
real problems.
From financial data to background processes.
A selection of what I'm working on.
REAL-TIME MONITORING & NOTIFICATIONS
Bitvavo Listing Radar
A monitoring system that automatically follows several sources and sends a push notification whenever it finds a relevant new listing.
Lead Developer
Read the case study 
WEB PLATFORM & PRODUCT DEVELOPMENT
Zimplix
An independent web platform where content can be updated through a simple management interface while the published website is generated as a fully static site.
Founder & Developer
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THIJS STEKELENBURGTHE PERSON BEHIND THE CODE
Curious about
making things better .
I'm Thijs, a software developer and student at mboRijnland. I build independent software projects under the name Stekelcode.
I'm interested in where systems meet: financial data, APIs and processes that could work better. I enjoy turning that complexity into something simple to use.
More about my backgroundMY TOOLKIT
The right technology.
For the right problem.
From API to interface.
An overview of my technical foundation.
Backend
Python · FastAPI · Django · Pydantic · REST APIs
Frontend / Apps
Flutter · Dart · JavaScript · HTML5 · CSS3 · Tailwind CSS
Data & Storage
PostgreSQL · SQLite · SQL · SQLAlchemy · Alembic
Infrastructure & Tools
Docker · Git / GitHub · Firebase Cloud Messaging · CI/CD · Automation
EXPERIENCE & DEVELOPMENT
Learning
by building.
- 2024 – Present
Independent Software Developer
StekelcodeDeveloping independent software architectures, including Wealth Hub (a financial portfolio app) and Bitvavo Listing Radar (crypto market monitoring). Working with FastAPI, Flutter, PostgreSQL, SQLite, Docker and push notifications.
- 2025 – Present
Founder & Developer
ZimplixDeveloping a website management platform with a static-first approach. Experience with structured JSON content, static compilers and product development.
I'm also studying Software Development (MBO 4) at mboRijnland in Leiden.
A GOOD CONVERSATION STARTS HERE
An idea, an opportunity
or a tricky problem?
I'd love to connect. About software, working together or the next step.
Send me a message [email protected]