CEO | Co-founder
2015 - PRESENTOm7Sense GmbH- Created the architecture, back ends, and front ends for Om7Sense, an IoT startup focusing on data centers using React for the front end.
- Developed back ends consisting of high-availability OSGi containers written in Java running in Eclipse Kura on embedded Linux.
- Stored data in MySQL in a hierarchical fashion that can support years of high-resolution usage data on a 32 GB device.
- Implemented real-time communication using MQTT between the front end and back end.
- Built a mesh of nodes with distributed permissions according to the IoT gateway/concentrator concept.
Technologies: Kotlin, Webpack 4, Webpack 3, MySQL Server, HTML5, Git, JavaScript, SQL, REST APIs, Web, Java, Linux, Embedded Linux, MySQL, Node.js, OSGi, Eclipse, ReactAndroid Security Engineer
2019 - 2020Yinkozi- Maintained and extended a low-level security library for Android, containing encryption, device integrity checks, and anti-tampering.
- Migrated an Android app from Jetpack/Android X to the Android Support library.
- Supported an app by creating an installer for the Android library.
- Wrote a Gradle plugin for SDK/library for Android.
- Improved documentation and wrote quick-start documentation.
Technologies: Android NDK, C, Git, Android SDK, Android, Linux, Bash, Java, C++, GradleConsultant
2018 - 2018Microsoft- Consulted on technical due diligence.
- Interviewed developers to judge experience and team workflow.
- Reviewed code and source code history for quality.
- Reviewed the IP and licensing.
- Analyzed an Android app's architecture, security, and resilience.
Technologies: Git, Android, Continuous Integration (CI), Angular, JavaScript, JavaFreelance Mobile Developer
2014 - 2018Börse Go AG- Created a strong-but-fast library for embedding v8 into Android apps to use web-based libraries without resorting to web views. V8 runtime uses OpenGL ES to expose JavaScript canvas, WebSockets, AJAX, and more to the JavaScript side.
- Helped develop a rich phone/tablet app that shows real-time financial data in a comprehensive but visually striking way.
- Integrated a client's powerful finance JavaScript charting library into the app.
- Migrated a large legacy Java codebase to Gradle, Kotlin, and RxJava.
- Implemented strong Material UI in cooperation with the design team and iOS team.
Technologies: Android NDK, RxJava 2, C, Git, JavaScript, SQL, Android SDK, REST APIs, Linux, OpenGL, V8, C++, RxJava, Kotlin, Java, AndroidWeb Developer
2016 - 2016ProSiebenSat.1 Media SE- Developed multiple landing sites.
- Integrated streaming video into a web page.
- Conducted rapid prototyping and worked with a visual designer.
Technologies: MySQL Server, Git, Web, JavaScript, Sass, HTML5Android Developer
2016 - 2016Amphiro AG- Created an Android app from scratch that collects and visualizes data from a client's IoT water usage measuring device.
- Implemented the background and a power-efficient Bluetooth LE data retrieval feature that was compatible with the maximum number of Android devices.
- Conducted large-scale matrix testing of devices and OS versions.
- Executed real-time synchronization with the back-end, supporting multiple data sources updating together.
- Created a graph visualization of the water usage.
Technologies: Git, Java, Android, Bluetooth LESoftware Engineer
2015 - 2015Cliqz GmbH- Created a mobile browser based on an open-source framework in Java and JavaScript; also helped with the iOS version (Objective-C).
- Converted a search engine UI that only ran as a Firefox extension to run as a Chrome extension; both in the mobile app and stand-alone website, migrating from ES2015 to ES5 JavaScript.
- Extended the open-source mobile messenger, Telegram, with a search interface and multi-modal photo sharing while working closely with the product designer.
- Created the Places API's infrastructure including the document schema, storage, and REST API.
- Researched search engine data sources for the mobile web.
Technologies: Git, SQL, REST APIs, Web, CSS, HTML, Android, JavaScript, JavaMobile Developer
2014 - 2014Purelabs UG- Developed an in-car navigation experience that coupled sound and video the points of interest.
- Implemented a Google Maps API with geofences downloaded from a REST API to activate the audio/video scenes while driving.
- Used Android Multimedia APIs to play multiple sounds in parallel and move the stereocenter point.
- Simulated 2D positional audio by using accelerometer sensor data.
- Stored and replayed geodata from a live drive so that customer can work on simulation outside of a car.
Technologies: Git, Geofencing, Java, Android, Google MapsMobile/Web Developer
2009 - 2014BörseGo AG- Developed the company's Android apps in the financial sector with a focus on real-time data and on-device charting using Java. The app was featured in the Play Store twice.
- Led a team of three in developing a single-page HTML5/JavaScript app that showcases chart patterns. Worked with clients on customizing the white-label version of this product.
- Worked in a small team rebuilding the main web franchise that sees multiple million visits per month from static HTML to a mixed statically/dynamically rendered version written in JavaScript and a REST API in PHP/MySQL.
- Developed a custom blogging engine with cascading comments as a REST API in PHP/MySQL with a custom web cache for performance and a PHP front-end. Also integrated it with the in-house WordPress CMS.
- Written and optimized multiple REST APIs in PHP and their corresponding MySQL queries using KCachegrind and other profilers.
- Supported and extended a customer webshop written in Django/Python.
- Maintained multiple customer websites in PHP/MySQL.
Technologies: Android NDK, MySQL Server, C, HTML5, Git, SQL, REST APIs, Web, Linux, CSS, HTML, MySQL, PHP, JavaScript, Java, AndroidStudent Researcher
2006 - 2009University of Koblenz and Landau- Built a campuswide news broadcast system that sent the news to feature phones via Bluetooth; it was implemented in Java EE on OSGi embedded devices.
- Developed a back-end service and for campus news network in C++.
- Designed the protocol for bidirectional communication through Bluetooth and running over a GPRS connection so minimal data use and resiliency was required.
- Created a multiscreen ticker-on-TV interface for campus news shown on TV monitors in Python/OpenGL.
- Worked on multiple research papers and proof-of-concepts in the area of AI.
Technologies: Web, Bluetooth, OSGi, Java EESoftware Engineer
2005 - 2006wizAI GmbH- Extended and maintained a news-clipping service that implemented full-text indexing of news articles running on Java EE.
- Migrated a news clipper from MySQL to a Lucene full-text search engine for a better performance.
- Optimized the clipping engine's performance for scaling up to 10x.
- Worked on the website and database using PHP and MySQL.
- Maintained and managed the Linux servers.
Technologies: MySQL Server, C, REST APIs, Web, Java, MySQL, Apache Lucene, Java EECo-founder | CTO
2002 - 2003Selador- Co-founded and incepted a web-based multiplayer game using PHP and MySQL.
- Optimized the game for high concurrency, low-latency server-side rendering using a custom event pipeline.
Technologies: CSS, MySQL Server, HTML5, SQL, Web, JavaScript, HTML, MySQL, PHPDevOps | SysAdmin
1998 - 2002InnNet GmbH- Built and maintained Linux servers for an internet service provider with web servers (Apache), databases (MySQL), and mail services (Sendmail/Courier).
- Set up an internet infrastructure and routing using Cisco and Bintec routers (OSPF).
- Installed the dial-in infrastructure (ISDN, GSM).
Technologies: Web, Sendmail, TCP/IP, MySQL, Apache, Linux