# Obaid Ur Rehman

> Full stack software engineer in Aachen, Germany, with nine years across backend, web, and embedded systems. Currently at Topsonic Systemhaus GmbH, building aircraft noise and flight track monitoring software for airports worldwide. Strongest in C#/.NET and Java backends, distributed systems, and performance and cost optimization. M.Sc. Data Science, RWTH Aachen. Authorized to work in the EU.

## Contact

- Email: obaidpunjab@gmail.com
- Website: https://obaid.tech/
- LinkedIn: https://www.linkedin.com/in/obaidpakistan/
- GitHub: https://github.com/obaid-ur-rehman
- Location: Aachen, Germany
- Resume as PDF (English): https://obaid.tech/Obaid_Ur_Rehman_Resume.pdf
- Lebenslauf as PDF (German): https://obaid.tech/Lebenslauf_Obaid_Ur_Rehman.pdf

## Experience

### Full Stack Software Developer, Topsonic Systemhaus GmbH, Würselen, Germany (Jan 2025 - present)

Topsonic builds aircraft noise and flight track monitoring systems for airports worldwide.

- Builds and extends C#/.NET desktop applications and Vue.js web applications for aircraft noise and flight track monitoring deployed at airports internationally
- Automated release and deployment pipelines and designed the high availability environment for production monitoring services
- Profiles and optimizes application performance, and designs REST APIs and database models for flight and measurement data
- Reviews teammates' code and contributes to software architecture decisions

### Backend Developer, Better Mobility GmbH, Aachen, Germany (Jan 2022 - Dec 2024)

Multimodal mobility app serving over 500,000 users across five cities.

- Built Java microservices in Quarkus and Spring for a multimodal mobility platform serving over 500,000 users across five cities
- Cut map tile spend from 2,000 USD to 300 USD per month, an 85% reduction, by introducing disk-based tile caching
- Reduced place search query time from 300 ms to 40 ms, a 7.5x speedup, by adding Redis caching
- Improved POI search recall for partial and misspelled place names by tuning fuzzy matching in Elasticsearch
- Integrated five mobility providers, three on the GBFS standard and two on manufacturer-specific APIs
- Built a GraphQL filter service, developed OpenStreetMap data analysis algorithms, and optimized navigation routing with GraphHopper
- Contributed to software architecture, ran code reviews, and wrote unit and integration tests

### IoT Engineer, Synodic Inc, Remote (Jan 2017 - Dec 2021)

Electronic logging devices for commercial fleets in the US and Canada.

- Wrote C firmware for electronic logging devices, parsing J1587, J1939, and J1979 vehicle bus data from truck ECUs
- Scaled over-the-air firmware deployment to more than 7,000 devices in the field across the US and Canada
- Built a J1939, J1979, and J1587 protocol simulator for automated ELD testing without physical vehicles
- Integrated BLE and in-memory engine protocols, and built an Android app for event synchronization
- Developed a Java server for DOT and CCMTA compliance reporting

### Working Student, Software Development, e.GO MOOVE GmbH, Aachen, Germany (Mar 2021 - Sep 2021)

- Developed ROS 2 software for autonomous electric shuttles
- Integrated sensors including LiDAR and GPS
- Improved point cloud processing and object detection
- Assembled and tested hardware units

## Education

- Master of Science, Data Science, RWTH Aachen University (2021 - 2024)
- Bachelor of Science, Software Engineering, COMSATS University Islamabad (2013 - 2018)

## Skills

- Programming languages: C#, Java, C, C++, SQL, JavaScript/TypeScript, HTML, CSS
- Backend and web: .NET (ASP.NET Core, WPF, .NET Core), Spring, Quarkus, Microsoft Orleans, Vue.js, REST, GraphQL, microservices
- Databases and messaging: PostgreSQL, MySQL, MSSQL, Redis, Elasticsearch, Apache Kafka
- DevOps and tooling: Docker, Kubernetes, GitLab CI, GitHub Actions, Git, Linux, CI/CD automation, high availability deployments
- Embedded and hardware: C firmware, OTA updates, BLE, ESP-IDF, PlatformIO, ROS 2, EAGLE, EasyEDA, Autodesk Fusion 360, OnShape
- Practices: code review, software architecture, unit and integration testing, performance profiling

## Languages

- English (C1)
- German (B1)
- Urdu (native)

## Projects

- ELD Device and ECU Simulator: a device that records driver working hours, connects to a vehicle's ECU, stores the data, and transmits it to a central server, paired with a simulator that emulates vehicle protocols for testing ELDs
- Autopilot Board for Fixed-Wing Drones: an autopilot board for fixed-wing drones with GPS, IMU, and high-resolution LiDAR sensors

## Note

This site was generated with generative AI. All CV content was provided and reviewed by Obaid Ur Rehman.