Resigned the previous job to take time off for familial reasons. Started a few personal projects to gain more experience in technologies e.g. React, vite.
Pocket
- Personal bookmark web application written in TypeSript, React & vite.js for the frontend, using Rust, axum, GraphQL & Postgres for the API server.
- Supports user authentication, site download, Markdown-based reader view, collections, tags, text search, dark / light themes, Wayback API integration.
gloss-rs
- A 3D graphics library built with Rust & webgpu, to expand knowledge on shader programming (WGSL), and to showcase advanced Rust features, e.g. macros, traits, async, design patterns.
Ferrous Systems GmbH
- Senior Software Developer
Germany's first Rust consultancy & training company. Developer of Ferrocene, the first qualified Rust compiler (ISO 26262, IEC 61508 & others). The Ferrocene Language Specification (FLS) has been adopted by the Rust Language team.
Ferrocene
- Developed the Customer Portal, the customer facing web application (Ruby on Rails) to manage organizations / teams to access the Ferrocene releases, implemented subscriptions via Stripe
- Expanded the API web service (Rust) to provide access to Ferrocene release downloads with authentication
Ferrous Systems
- Member of the on-call rotation for crates.io between August 2021 - January 2025
- Co-trainer in several Rust workshops
- Technical interviewer in application process
HickoryDNS (Blog post)
- Expanded DNSSEC support to
hickory-dns, a Rust suite of dns utilities, as part of a STF funded project, by implementing relevant RFCs 4035, 6840 & others
- Developed an extensive conformance test suite to track progress, to check feature parity and to manage non-standard / unspecified behavior
- Discovered, fixed and tested about two dozen DNSSEC related issues in the existing implementation
Stackable (Blog post)
- Added support for multiple versions of the CycloneDX specification to the
cargo-cyclonedx library to help improve supply chain security in the Rust ecosystem
- Refactored validation logic to provide better localized error messages, while improving readability of tests
Graphiant
- Tracked IPMI specific sensor data in Rust, expanded existing schema models using YANG, then built new API endpoints to provide access to this data
- Rebuild the web interface of a diagnostics tool, used to inspect live systems, by following HTTP best practices
Cybertec
- Prototyped a Postgres language parser to migrate PL/SQL code to PL/pgSQL in Rust
- Developed a lexer, parser & analyzer to build an AST representation (using libraries logos & rowan) to then generate SQL code from
Asquera GmbH
- Senior Software Developer
Software consultancy with roots in the Ruby community, focussing on backend development, API design, databases, distributed systems, CI / CD. Provider of Elasticsearch workshops.
LGB Potsdam
- Developed the Search API using Python & flask to provide search of public geodata
- Configured Elasticsearch to support location based search, including automated Logstash workflows, index rotation and rollback
- Set up project with test framework, CI / CD pipelines for easy deployment, Swagger & Open API for documentation, and a containerized environment for local development
AboutYou
- Expanded & improved product search for different e-commerce shops using Elasticsearch, Redis and PHP
- Automated workflows to transform & ingest products for full text search with index rotation & rollback support, set up CI / CD, fixed slow queries
- Provided backend support to customize full text search per shop (support for synonyms, highlighting, stopwords)
Marley Spoon
- Maintained & refactored an internal web application (Ruby on Rails) used in fullfilment centers world wide
- Optimized SQL queries in Postgres to improve API response times significantly (up to 90%)
- Transferred infrastructure of web application and its services to AWS & Kubernetes with Docker, Helm, Helm-charts
- Set up monitoring using Prometheus & Grafana, provided 24/7 on-call support
filiadata / DM
- Built Puppet modules to deploy Elasticsearch, Logstash, Kibana using Foreman, including CI / CD setup with Jenkins and Docker
- Implemented authentication mechanism to manage ~20 applications among all teams, with configurable log retentions times, e.g. daily, weekly
- Provided documentation & templates for teams, to configure sources & to build Kibana dashboards
Pro7 / Sat1 Media AG
- Built an API using Ruby & Padrino to provide mobile clients access to the Electronic Program Guide (EPG) including full text search
- Implemented search capabilities via Elasticsearch, configured data ingestion from documents in CouchDb
Other Activities
- Trainer in Elasticsearch workshops
- Worked on ~20 client projects, e.g. SysEleven, T-Systems, HERE, Wheelmap.org, dozeo
Software Diagnostics
- Software Developer
Visual Studio C++ IDE Plugin
- Expanded a VS IDE plugin to manage C++ projects to record runtime traces, including variables and real time stack traces
- Improved data layout to minimize export data, optimized import of trace data from exponential to near linear performance, which resulted in load times of multiple GB down to a few seconds
exozet games
- Mobile Game Developer
Various Games
- Developed a number of games using J2ME (Java), for example Settlers of Catan, Hey That's My Fish, The Three Investigators
- Prototyped 3D games for mobile phones