IOANNIS KATRIMPOUZASSENIOR SOFTWARE ENGINEERBERLIN
I build systems that keep moving.
Career flight log · 2018 to now
A journey through
systems & scale.
Five companies. One through-line: making difficult systems calmer, faster, and safer to evolve.
- Dec 2024–Present05
Redcare Pharmacy
Senior Software Engineer
Berlin, Germany
Own the backend services powering key parts of the storefront experience for one of Europe's largest online pharmacies. Responsible for backend architecture, system modernization, production reliability, and the evolution of a high-traffic e-commerce platform.
- Led a large-scale CMS migration, designing API contracts, data transformation workflows, and progressive production rollouts across seven European storefronts with zero downtime.
- Designed backend services and integration workflows supporting CMS modernization, balancing real-time data consistency with API performance through Redis caching and feature flags.
- Authored Architecture Decision Records (ADRs) and collaborated closely with Staff Engineers, Platform Engineering, Frontend, and Operations teams on architectural decisions and production migrations.
- Owned production observability by creating Grafana dashboards, defining alert thresholds, investigating incidents with Grafana and Kibana, and improving service reliability.
- Optimized Kubernetes autoscaling and backend performance to support peak traffic events, including Black Friday, while maintaining reliable production operations.
- Apr 2023–Nov 202404
RECUP
Senior Full Stack Engineer
Berlin, Germany
Built and evolved a greenfield cloud-native platform for Germany's largest reusable deposit system, supporting partner onboarding, customer management, and business-critical integrations. Owned significant parts of the backend architecture while collaborating closely with engineering, product, sales, and operations teams.
- Selected and designed the backend architecture using NestJS, Prisma, PostgreSQL, Google Cloud Pub/Sub, and Cloud Functions, including API design, database modelling, and event-driven communication.
- Led the implementation of integrations with Stripe, HubSpot, Weclapp, and BigCommerce, combining REST APIs, webhooks, scheduled jobs, and asynchronous messaging to support subscriptions, CRM, ERP, and e-commerce workflows.
- Redesigned the customer onboarding flow by introducing asynchronous payment verification, reducing perceived registration time from ~20 seconds to under 5 seconds while maintaining business rules.
- Authored Architecture Decision Records (ADRs) and regularly drove technical discussions around architecture, integrations, and backend design.
- Improved engineering quality by introducing automated testing (Jest & Playwright), API documentation (OpenAPI/Swagger), security scanning (Snyk), code quality analysis (SonarCloud), and CI/CD pipelines with GitHub Actions and Google Cloud Build.
- Jun 2021–Mar 202303
Lendis
Full Stack Engineer
Berlin, Germany
Built and evolved backend systems supporting the logistics platform of a rapidly growing Device-as-a-Service (DaaS) company, contributing to one of the company's largest engineering initiatives: modernizing a Laravel monolith into an event-driven microservice architecture on AWS.
- Led significant parts of the migration from a Laravel monolith to an event-driven microservice architecture, designing service interactions, defining migration tasks, and implementing backend services using AWS EventBridge, Lambda, SNS, and DynamoDB.
- Designed a production validation environment that processed live production events, allowing internal logistics teams to validate the new platform before cutover and significantly reducing migration risk.
- Designed and implemented backend services supporting logistics, inventory, order fulfilment, and delivery workflows while introducing event-driven communication between services.
- Solved complex data migration and reconciliation challenges by developing migration scripts, integrating data from multiple external platforms, and resolving inconsistencies across legacy systems.
- Collaborated closely with engineering, logistics, and operations teams to modernize a business-critical platform, gaining deep expertise in distributed systems, event-driven architecture, eventual consistency, and service decomposition.
- Jan 2019–May 202102
Fast Fwd Multimedia Ltd.
Full Stack Engineer
West Midlands, England, United Kingdom
Built cloud-native applications across multiple customer projects for a digital agency and tech consultancy, developing a strong foundation in software engineering, API design, cloud technologies, and modern software delivery.
- Developed backend services and REST APIs using Laravel, contributing to customer-facing applications deployed on AWS.
- Built frontend features using React and TypeScript while collaborating closely with Product Owners and engineering teams to deliver new functionality and resolve production issues.
- Introduced automated end-to-end testing with Cypress, improving release confidence and reducing manual testing effort.
- Contributed to CI/CD pipelines, Docker-based development workflows, and cloud deployments while gaining hands-on experience with modern software delivery practices.
- Worked closely with Product Owners to translate business requirements into reliable technical solutions, continuously improving code quality and engineering practices.
- Apr 2018–Nov 201801
Lombard Risk
Java developer
Birmingham, United Kingdom
Started my professional software engineering career at a global fintech company developing software for the financial services industry. Contributed to the development and maintenance of regulatory reporting and collateral management solutions while building a strong foundation in backend development, software design, and agile engineering practices.
- Developed and maintained application features while resolving production issues and improving existing functionality.
- Collaborated closely with Product Owners and senior engineers to translate business requirements into reliable software solutions.
- Participated in code reviews, agile development processes, and iterative software delivery, continuously improving software quality and maintainability.
- Built a solid foundation in software engineering, debugging, testing, and collaborative development practices that shaped my approach to designing reliable production systems.
Applied AI · portfolio work
Exploring AI systems with production discipline.
I’m deepening my expertise in software engineering and distributed systems through structured study and a portfolio project that turns theory into working software. At the same time, I’m integrating Codex and GitHub Copilot into my daily development practice, exploring how thoughtful prompting and AI-assisted workflows can sharpen problem-solving, accelerate iteration, and improve the way software is designed and built.
Ioannis AI
Ioannis’ AI digital twin
Ioannis’ AI digital twin turns curated professional context into clear, grounded answers, helping visitors explore his experience.
- 01
LLM applications
Hosted and local models, RAG design, evaluation, structured outputs, function calling, and fine-tuning foundations.
- 02
Agentic systems
Tool use, orchestration patterns, shared state, guardrails, human approval, and MCP architecture.
- 03
AI-assisted delivery
Scoped planning, repository instructions, testing, review, sandboxing, subagents, and human accountability.
The next system
Let’s build something
that lasts.
For thoughtful conversations about platform modernization, distributed systems, production engineering, and applied AI.