Resume

Higgor Leimig

Specialising in distributed systems, serverless architecture, and building high-performing teams at scale.

Engineering Manager Jan 2026 – Present

Runa · London, UK

  • Leading a 4-person engineering team responsible for Fraud Prevention. Delivered features that reduced exposure and increased identification of fraudulent card transactions — cutting successful attacks from £150k to £4k.
  • Defined the framework used by Engineering leadership to understand and discuss Fraud Prevention within the platform, leading to concrete roadmap items to reduce fraud incidence.
  • Owned the team roadmap in lieu of a Product Manager.
Principal Software Engineer Mar 2023 – Dec 2025

Runa · London, UK

  • Technical leader of an Engineering Domain responsible for integration with 100+ suppliers.
  • Facilitated the onboarding and training of two newly established teams at a new company site in Sofia, Bulgaria — bringing them up to speed on the software they inherited as well as company culture and expectations.
  • Led migration away from the company monolith to serverless services, achieving a 97% reduction in API response time in one platform area.
  • Led technical discoveries that cut supplier integration time from 2 weeks to 2 days.
Senior Software Engineer Mar 2022 – Mar 2023

Runa · London, UK

  • Led system redesign that reduced internal manual work by 95% through automation of brand approval decisions.
  • Redesigned and rebuilt a web app serving 1.4M+ users/month, improving developer experience and reliability of a business-critical system.
Software Engineer Sep 2019 – Feb 2022

Klarna · Germany

  • Worked on Klarna's Bank Account core technology — refactoring and improving the Transactions system responsible for giving meaning to ledger entries and reconciliation.
  • Sole developer on an established team for three months — handled on-call responsibilities and viability research for future products.
JavaScript Developer Nov 2017 – Aug 2019

Viasto · Germany

  • Led performance optimisations resulting in a 66% performance increase of the main web application.
  • Rebuilt the company's core product technology in a tight timeframe, improving developer experience and customer satisfaction.
Software Engineer Jun 2015 – Nov 2017 & Jun 2010 – Apr 2014

CESAR · Brazil

  • Technical leader of a 20-person team across 2 sites in Brazil and the US.
  • Led performance improvement efforts delivering a 60%+ boost to a production web application.
MSc Software Engineering Aug 2016 – Aug 2018

CESAR School · Brazil

Researched cache schemes in Information-Centric Networks to improve IoT performance. Published IoT Caching in Information Centric Networks at IARIA 2017.

BS Computer Science Aug 2011 – Jun 2016

DeVry Brazil · Brazil

Co-created Annuit Walk, an assistive glasses system for vision-impaired people. Winner of the 2014 Youth Award.

Exchange Program Jun 2014 – May 2015

Temple University · USA

Awarded a competitive scholarship where applications outnumbered spots 16,000:1. Developed P910 in partnership with Temple University Campus Police to improve campus emergency call management.

Team Building & Mentoring
Problem Analysis & Roadmap Ownership
Cross-site Collaboration
Incident Management
Event-Driven & Serverless
Distributed Systems
API Design
System Migration
AWS
Python
TypeScript & JavaScript
Java
Fintech
Fraud Prevention
Payments