Sarah Hoffmann
Freelance Software Engineer
Greater Dresden Area Germany
Summary
🤩
Rockstar🎓
Top SchoolSarah Hoffmann is a freelance software engineer with 15 years of experience specializing in back-end systems and geocoding for OpenStreetMap-based projects. Her work spans senior engineering roles and research-driven development, including a PhD stint at ETH Zurich and long-term contributions at Kernkonzept. She has deep expertise modernizing search and import pipelines—refactoring Nominatim, enhancing Photon’s Nominatim importer with multithreading and robust address handling, and improving the OpenStreetMap Rails app’s geocoder and UI. Comfortable across application logic, database edge cases, and tokenizer/tooling migrations, she brings both production pragmatism and academic rigor to complex data problems. Based in the Greater Dresden area, she pairs strong system design skills with hands-on coding and a knack for improving data quality in large spatial datasets. One notable strength is translating research-level ideas into maintainable, multi-threaded import and search services used by major open-source geocoding projects.
15 years of coding experience
10 years of employment as a software developer
Computer Science, Psychology, Computer Science, Psychology at Technische Universität Dresden
Github Skills (18)
openstreetmap10
postgresql10
back-end-development10
geocoder10
java10
ruby10
rails-app10
javas10
sql10
database-design10
backend10
multithreading9
architectures8
architecture8
database-administration7
Programming languages (14)
Github contributions (5)
osm-search/Nominatim
Jan 2012 - Jan 2023
Open Source search based on OpenStreetMap data
Role in this project:
Back-end Developer
Back-end DeveloperContributions:38 releases, 151 reviews, 3237 commits in 11 years 2 months
Contributions summary:Sarah primarily refactored and improved the Nominatim project's codebase, focusing on modernizing the data handling processes. Key commits involved renaming libraries, migrating from the SQL to the ICU library for tokenizer, improving the address search mechanism, and implementing updates related to postcode and other features. These changes streamlined various search functionalities and improved the system's overall efficiency.
openstreetmapnominatimgeocodingosmopenstreetmap-data
komoot/photon
May 2014 - Nov 2022
an open source geocoder for openstreetmap data
Role in this project:Back-end Developer
Back-end DeveloperContributions:15 releases, 31 reviews, 313 commits in 8 years 7 months
Contributions summary:Sarah's contributions primarily focused on enhancing the Nominatim importer for the open-source geocoder. They implemented improvements related to address data, including fixing address levels for streets, removing place objects from the address list, and ensuring that countries are always added. Additionally, the user improved error handling, addressed null handling in database results, and introduced multi-threading for import processes. The user also made adjustments to include classification terms from the database and added handling for extracting housenumbers.
openstreetmap-datageospatialgeocodingphotonreverse-geocoding
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