Profile
Dr. Erik Stenman is a senior technology leader and systems architect with over 20 years of experience building and scaling distributed systems in fintech, telecom, and digital infrastructure, plus over 35 years of experience as an IT consultant. As Klarna’s first CTO and a core architect of its payment platform, he helped grow the company from startup to a European financial leader handling millions of secure transactions daily. Today, through HappiHacking AB, Erik advises and builds infrastructure for companies in regulated industries, combining technical depth in the BEAM ecosystem (Erlang/Elixir) with leadership in platform reliability, scalability, and compliance.
He thrives in environments that value trust, autonomy, and a “You build it, you own it” culture, exactly the principles driving Kivra’s next technical chapter.
Experience
HappiHacking AB
2014 – Present
Founder & CEO
- Leads a consultancy specializing in high-performance fintech and infrastructure systems.
- Built and operated systems processing 1+ billion daily events for clients such as Deutsche Telekom and Redcare.
- Mentors engineering teams and advises CTOs on platform modernization, observability, and compliance automation.
- Published The BEAM Book, now used by developers worldwide to understand the internals of Erlang/Elixir systems.
Klarna Bank AB
2005 – 2014
Chief Technology Officer → Chief Scientist
- Scaled Klarna’s tech organization from 1 to 80 engineers, establishing architecture, infrastructure, and engineering culture.
- Designed and led the evolution of Klarna’s core payment platform — secure, fault-tolerant, and built for continuous uptime.
- Championed distributed system resilience, observability, and developer empowerment long before “DevOps” became common practice.
Virtutech AB
2004 – 2005
Senior Developer
- Optimized the Simics full-system simulator, improving runtime efficiency and model fidelity for large-scale customers.
Selected Projects & Achievements
- Platform Modernization (Redcare) – Designed a future-proof payment orchestration layer for a leading European e-commerce platform.
- IoT Data Platform (Deutsche Telekom) – Architected a GDPR-compliant data pipeline handling 1B+ daily messages with fault-tolerant clustering.
- Blockchain Infrastructure (æternity) – Built a new BEAM-based blockchain, including the FATE VM for verifiable, efficient smart contracts.
- Cloud & Connectivity (Scania/Traton) – Interim Chief Engineer driving adoption of cloud-native vehicle connectivity architecture across brands.
Leadership & Mentorship
- Engineering Culture: Advocates a “You Build It, You Own It” mindset to align ownership with operational excellence.
- Team Development: Experienced mentor for engineering managers and senior ICs; builds calm, high-accountability teams.
- Strategic Influence: Bridges executive goals and platform realities, ensuring scalability, security, and compliance evolve together.
Education
Ph.D., Computer Science — Uppsala University (1999–2002)
Dissertation: Native Code Compilation and Optimization for Erlang (HiPE Project)
Postdoctoral Researcher, EPFL Lausanne (2003–2004)
Collaborated with Martin Odersky on compiler design and led the early Scala development team.
M.Sc., Computer Science — Uppsala University (1992–1996)
Core Competencies
- Leadership & Coaching for Engineering Managers
- Distributed & Fault-Tolerant Systems (Erlang/Elixir, Go, Kubernetes)
- Reliability, Observability & DevOps Practices
- Secure, Compliant Fintech Infrastructure
- Strategic Technical Direction & Architecture Governance
- Scalable Cloud Platforms (GCP, AWS)
- Cross-functional Collaboration & Communication
Publications & Speaking
- Author: The BEAM Book — comprehensive guide to the Erlang VM.
- Speaker: Code BEAM, Erlang Workshop, and fintech architecture events across Europe.
- Mentor & Advisor: Helps teams and founders build resilient systems that scale securely and sustainably.
Contact
📧 happi@happihacking.se 🌐 happihacking.com 🔗 linkedin.com/in/happi