Joakim Repomaa

Senior Software Engineer

Senior Full-Stack Engineer with deep expertise in Ruby on Rails backends, React/TypeScript frontends, and GraphQL/REST API design. Experienced in AI integration, external API partnerships, and analyzing large-scale data systems. Fluent in German, Finnish, and English. Passionate about system architecture, performance optimization, clean code, and pragmatic technical decision-making in fast-paced product environments.

[E] [email]

[L] Espoo - Finnland

[G] github.com/repomaa [W] joakim.repomaa.com

$> experience

Senior Software Engineer

hundertzehn GmbH • Zürich, Schweiz

2021 — Present

Full-Stack Engineer for MOCO Cloud-ERP-SaaS serving 7'500+ SMEs. Develop Ruby-on-Rails backend, REST/GraphQL APIs, React/TypeScript frontends. Analyze large datasets, evaluate new technologies, integrate external APIs (Paywise), direct customer communication. Leading AI integration including Support Agent and MCP functionality. Key technical figure in SaaS product context ensuring platform stability at 60'000 daily active users.

Ruby on RailsTypeScriptReactPostgreSQLGraphQLREST APIsGrafana

Software Engineer

MESO Digital Services GmbH • Frankfurt, Germany

2014 — 2021

Developed software solutions for digital communication, IoT platforms, and cloud services. Key projects: Energybox - high-resolution big data IoT platform processing 1 billion+ data points daily with horizontally scalable sensor cloud backend, API, and frontend. HERE Technologies - experience platform and CMS for CES showcasing location intelligence. HfG Offenbach - database-driven university website with custom CMS for content management.

CrystalRuby on RailsJavaScriptMongoDBREST APIsIoTBig Data

$> education

Bachelor of Science

Applied Computer Science • Wiesbaden, Germany

2010 — 2016

Bachelor thesis: 'Collaborative Content Creation' - built a scalable CMS with real-time collaboration, hierarchical caching, and JSON-API using Crystal and Redux