Rafal Cymerys
CTO & Managing Partner at Upside
Berlin, Germany
Summary
🤩
Rockstar🎓
Top SchoolRafal Cymerys is a CTO and managing partner based in Berlin with 11 years of experience building and scaling complex digital commerce systems. He leads Upside, a full-stack agency that helps scale-ups and enterprise brands like Samsung and T-Mobile, while remaining hands-on in backend engineering. A longtime Spree core contributor, Rafal has implemented critical e-commerce API endpoints and starter template fixes that improve multi-store and multi-currency workflows. His background spans big data and microservices at Nielsen, plus early optimization work on crew recovery systems, reflecting comfort with both data-intensive and transactional systems. Pragmatic and product-focused, he combines engineering depth in Ruby on Rails and distributed systems with leadership in Agile and lean delivery.
11 years of coding experience
4 years of employment as a software developer
BS Computer Science, BS Computer Science at AGH University of Krakow
English, Polish, German
Github Skills (18)
apim10
ruby-rails10
api-design10
ecommerce10
rails10
ruby10
api10
spree10
ruby-on-rails10
spreed10
storefront9
database-migrations9
apidoc9
webstore9
configuration-management9
Programming languages (5)
Github contributions (5)
spree/spree_starter
Sep 2022 - Jan 2023
@spree application starter template
Role in this project:
Back-end Developer
Back-end DeveloperContributions:4 releases, 11 reviews, 52 commits in 4 months
Contributions summary:Rafal's contributions primarily involve modifying the Spree application starter template. Their work includes fixing the devise initializer, adding migrations from Spree 4.5, and updating application and environment configurations, including the time zone and default URL options. They also fixed the default assets port in the development environment and addressed deployment-related configurations by preventing the loading of seeds during deployment.
templateecommercecommercerailssolidus
spree/spree
May 2019 - Jan 2023
An open source eCommerce platform giving you full control and customizability. Modular and API-first. Multi-vendor, multi-tenant, multi-store, multi-currency, multi-language. Built using Ruby on Rails. Developed by @vendo-dev
Role in this project:Backend Developer
Backend DeveloperContributions:11 releases, 88 reviews, 60 commits in 3 years 8 months
Contributions summary:Rafal contributed to the backend functionality of the Spree eCommerce platform. Their commits focused on fixing store query issues in the admin page and implementing API endpoints for associating guest orders with user accounts. They also added an API endpoint for changing cart currency and returned filter options with the products API. These changes involved modifying core application files, API controllers, and service implementations to enhance the platform's features and address specific functionalities.
multi-sourceecommercemulti-languagespreecommerceshopware
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