Wolfram Arnold
Founder at Stealth
The Hague, South Holland, Netherlands
Summary
👤
Senior🎓
Top SchoolWolfram Arnold is a Staff ML Systems Engineer with 17 years of experience building production-grade ML infrastructure and feature platforms for large-scale consumer products. He founded and scaled Twitter’s Feature Management Team and shipped the company-wide Feature Store, and at Cruise he architected a natural-language image-mining pipeline that produced ~1B embeddings and cut miner iteration time by 100x while boosting precision dramatically. Equally comfortable leading teams and writing production code, he has deep roots in Ruby/Rails back-end engineering and notable open-source contributions to widely used projects like Active Merchant and RailsAdmin. His background — a physics PhD and early startup CTO/founder roles — explains a blend of analytical rigor, rapid prototyping, and product-focused engineering that repeatedly turns research-grade models into reliable, customer-facing systems. Based in The Hague, he combines cross-functional leadership with hands-on system design, and has a track record of improving both technical quality and team diversity.
17 years of coding experience
21 years of employment as a software developer
Doctor of Philosophy - PhD, Physics, Doctor of Philosophy - PhD, Physics at University of OregonDiplom, Physics, Diplom, Physics at Ulm University
English
Stackoverflow
7,235reputation
551kreached
77answers
25questions
encoding
top-5%
ruby-on-rails
top-5%
scala
top-5%
v8
top-5%
javascript
top-5%
heroku
top-5%
Github Skills (28)
ruby-rails10
apidoc10
payment-gateway10
rails10
ruby10
api10
tdd10
activerecord10
javascript9
scala9
paypal9
v89
configuration-management9
encoding9
heroku9
Programming languages (7)
Github contributions (5)
railsadminteam/rails_admin
Mar 2011 - May 2011
RailsAdmin is a Rails engine that provides an easy-to-use interface for managing your data
Role in this project:
Back-end Developer
Back-end DeveloperContributions:12 commits in 2 months
Contributions summary:Wolfram primarily contributed to the RailsAdmin engine, focusing on back-end logic and configuration. They refactored model label configuration, moving it from the section level to the model level, and updated related code references. They also implemented a whitelist approach for model administration using `included_models` and corrected a bug related to handling namespaced models within the RailsAdmin application. Further contributions included code comment cleanup and fixing an edge case in the history functionality.
rails-adminrails-engines
activemerchant/active_merchant
May 2011 - May 2011
Active Merchant is a simple payment abstraction library extracted from Shopify. The aim of the project is to feel natural to Ruby users and to abstract as many parts as possible away from the user to offer a consistent interface across all supported gateways.
Role in this project:Back-end Developer
Back-end DeveloperContributions:8 commits in 1 day
Contributions summary:Wolfram's primary focus was on enhancing the `active_merchant` library's integration with the Payflow Express payment gateway. They added support for order line items and the `allow_note` flag, expanding the features available to users of the library. Furthermore, the user incorporated the ability to include comment fields (comment, comment2) in Payflow transactions, which will be reported to the Payflow backend. They also made documentation updates.
activemerchantrubyshopify
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.