01 / Selected work

Selected work

Projects across algorithms, geospatial interfaces, software testing, full-stack systems and embedded interaction.

TSP Algorithm Lab

Algorithm visualisation · Full-stack

Problem

Algorithm results are difficult to compare when route quality, runtime and search behaviour are separated across different tools.

What I built

A React and TypeScript interface with a Java and Spring Boot backend that parses TSPLIB instances and compares multiple TSP approaches through graph and map views.

Decision note

Keep the dataset constant while changing the algorithm, so differences in route quality and runtime remain visible.

What I learned

Heuristic behaviour becomes easier to explain when the search process is visual, not only numerical.

TSP Algorithm Lab: ranked comparison of four Simulated Annealing implementations on ch130, listing tour length, runtime and delta for each candidate — Simulated Annealing comparison

ReactTypeScriptJavaSpring BootTSPLIBAlgorithms

View repository↗

Biodiversity Warehouse

Geospatial data · Frontend

Problem

Large biodiversity datasets are difficult to explore when records, species filters and geographic context are separated.

What I built

An interactive geospatial interface that combines species filtering, UTM-based views, clustered records and multiple map layers.

Biodiversity Warehouse: species, family and order filter panel over the interactive UTM grid map of Germany — Species filters and UTM grid

Decision note

Show different information densities at different map scales instead of forcing every record into one view.

Biodiversity Warehouse: clustered species records over a UTM grid of Germany, with an active species filter and a live legend — Filtered records / clustered distribution

What I learned

Geospatial interfaces become clearer when filters, aggregation and zoom level work together.

VueTypeScriptOpenLayersUTM

View project↗

EV Charging Infrastructure

Geospatial · Data

EV Charging Infrastructure: AC and DC charging stations plotted across the Bremen region via GeoServer WMS — AC and DC stations

A containerised WebGIS platform that visualises 104,117 German EV charging-station records through PostgreSQL and PostGIS, GeoServer WMS/WFS services, and an interactive OpenLayers interface.

Challenge

104,117 charging-point records stay usable because PostGIS and GeoServer WMS serve only what the current map view needs.

Takeaway

Let the database and the map server do the heavy lifting — the client should only ask, not compute.

PostGISGeoServerOpenLayersDocker

View repository↗

Escape Room Puzzle System

Physical computing

Physical input → puzzle logic → validation → servo unlock

Finished physical escape-room puzzle system with buttons, keypad, displays and modular controls — Finished puzzle system

Firmware and logic overview of the escape-room puzzle system — Firmware / logic diagram

A modular Arduino puzzle system developed as part of an escape-room course project, featuring logic-gate, binary-conversion and code-entry challenges with LCD, servo, button and progression-control integration. The public repository contains sanitised material related to my own contributions.

Challenge

Keeping chained puzzles deterministic: buttons, keypad and displays talk over I2C, and progression only advances when wiring and firmware agree.

Takeaway

Debugging changes when state lives in hardware — the fault can sit in the circuit, in the code or in the connection between them.

ArduinoC++I2CElectronics

View repository↗

Spor Toto Test Automation

End-to-end testing · Software quality

Test strategy

The tests treat the application as a user would: entering through the interface, verifying protected behaviour and checking that critical flows remain stable across viewport sizes.

Risk map

01Authentication
02Protected routes
03Session handling
04Responsive layouts
05Regression confidence

Evidence

tests/route-protection.spec.ts

test("anonymous access to /admin redirects to the login page", async ({ page }) => {
  const admin = new AdminPage(page);
  await admin.goto();
  await expect(page).toHaveURL(/\/giris\?next=%2Fadmin/);
});

A real check from the suite: an anonymous visit to /admin must land on the login page with the original destination preserved — spoofed client-side session values included.

3 spec files · 9 scenarios · 15 cases per browser project
Chromium · Firefox · WebKit · Mobile Chromium (Pixel 7)
GitHub Actions workflow: playwright.yml

What it protects

The suite protects authentication boundaries, navigation rules and critical user flows from silent regressions.

What I learned

End-to-end tests are most useful when they are tied to product risks, not only UI elements.

PlaywrightTypeScriptCI/CDPOM

View repository↗

Fokur Toto Ligi

Product · Full-stack

An invite-only football prediction platform with weekly 1/X/2 picks, prediction deadlines, automated scoring, leaderboards, weekly results and player history.

Challenge

Weekly rounds live and die by trust: deadlines, automated scoring and rankings have to be reproducible from the stored predictions.

Takeaway

In a small league product, transparent scoring matters more than any additional feature.

Next.jsReactTypeScriptSupabasePostgreSQL

View repository↗

Burada — Android Attendance App

Early project · Android

System overview diagram of the Burada Android attendance and student-information application — System overview (diagram)

My first substantial Android application and bachelor's graduation project from 2021: a Java-based attendance and student-information prototype with QR scanning, schedules, grades, course materials and notifications. Preserved as a historical milestone in my development journey.

Challenge

Attendance, schedules, grades and notifications as one solo Java and XML project — with application state kept in SharedPreferences.

Takeaway

What I would approach differently today: clearer separation of data, UI and platform responsibilities.

AndroidJavaXMLSharedPreferences

View repository↗