Solution Architect / Senior Software Engineer (sports data pipeline, settlements, LLM API layer) at Freelancer

• Redesigned and implemented a high-volume sports data pipeline for live timelines and real-time statistics, reducing per-stat computation time (~17%) and increasing single-instance throughput (~12%) • Designed and developed market settlement logic to determine bet outcomes based on the generated statistics • Built and trained predictive models in Node.js (TensorFlow.js) to calculate the combined performance of two bets, reaching 97% agreement with competitor-quoted values for the same inputs • Created a Node.js API layer over self-hosted LLMs via Ollama with dynamic model selection • Partnered with product stakeholders to deliver robust, supportable architectures

Freelancer - Squad & Technical Leader (VAaaS cybersecurity platform) at Freelancer

• Owned architectural decision-making with ADRs and diagrams, aligned delivery priorities with the CTO, and ran code reviews • Translated partner requirements into focused task plans and improved onboarding with standards and a feature-based structure • Led a mixed-seniority squad of three engineers as Squad Leader and Scrum Master, delivering a VAaaS cybersecurity platform that automates network service discovery scans for infrastructure assessment • Increased delivery throughput by 15% through ahead-of-time task refinement and fast resolution of impediments • Shaped the delivery roadmap and moved the team from an ad hoc process to a hybrid Scrum - Kanban framework within the first two months, through hands-on coaching, mentoring and monthly one-to-ones on skills growth • Contributed to hiring through technical assignments and reviews

Senior Software Engineer (Azure platform governance, CI/CD, notifications, monitoring) at T-Digital by Deutsche Telekom

• Improved security, reliability, and compliance by addressing vulnerabilities and strengthening governance • Evaluated device management service architecture against security and operational standards • Orchestrated applications across Azure environments using CI/CD and AKS, streamlining pipelines and supporting migrations to reduce deployment risk • Used Azure Log Analytics to speed up incident resolution, optimized high-load notification delivery with batch processing and read/write isolation • Conducted Node.js technical interviews covering async patterns and database concepts.

Solution Architect / Senior Software Engineer (GraphQL gateway, CMS versioning, messaging, Vue/Fastify redesign) at Freelancer

• Optimized and governed a GraphQL gateway consolidating multiple APIs into a single endpoint, reducing latency by 20% and improving scalability • Redesigned an Express/jQuery monolith into independently deployable Vue.js and Fastify services, reduced database tables (18 to 10) using PostgreSQL JSON/intarray, and secured APIs for mobile clients • Built a RabbitMQ integration layer in Node.js with failover, connection status events, and reliable delivery across broker outages • Delivered CMS content-versioning architecture with OpenAPI-documented APIs, Grafana production dashboards, and architectural documentation/diagrams to guide platform evolution

Solution Architect / Senior Software Engineer (advertisement delivery platform) at Weborama

• Led architecture and hands-on development of a distributed, high-transaction advertisement delivery platform (Node.js, Fastify, PostgreSQL, Redis, RabbitMQ) • Owned stakeholder-aligned architectural decisions and mentored junior developers • Cut monthly infrastructure cost by 95% by right-sizing HAProxy and services, improved throughput by 15% using loader.io tests • Designed CQRS and event-driven services to separate high-volume reads from writes absorbing traffic spikes • Established API governance with OpenAPI Spec, giving teams consistent contracts and a managed API lifecycle • Implemented a Node.js service that monitored file changes, automated file upload to the CDN via SFTP, and purged outdated versions, cutting advertisement update time from a couple hours to less than a minute • Built a centralized email dispatch microservice, replacing per-application email handling across four applications • Automated provisioning and deployment with cloud-config scripts, Dockerfiles and a CLI for multi-server script rollout

Senior Software Engineer (integration automation, security, device integration) at ING

• Designed and implemented a JSON-configurable mock server in Node.js/Express to simulate in-development REST APIs, reducing integration wait time by at least two sprints (~4 weeks) • Built an oclif plugin that runs Mocha/Chai tests in deployment and release pipelines across 25+ teams • Conducted OWASP-based security assessments and remediated vulnerabilities • Replaced ActiveX with a vendor driver API for signature pads to enable cross-browser support • Developed reusable web components using lit-html to improve modularity and maintainability

Senior Software Engineering Consultant at WAES (consultancy company)

• Reviewed and provided feedback on technical assignments, ensuring alignment with architectural standards; supported hiring decisions through rigorous evaluation

Solution Architect / Senior Software Engineer (loyalty, notifications, offline-first app) at Enginius

• Owned solution design for a loyalty platform (earn/transfer/redeem across partners), a batch and personalized notification service, and an offline-first tourist app that syncs updated data on startup • Selected Heroku for cost-efficient deployment and PostgreSQL over MySQL/MariaDB for fit with managed cloud offerings, saving 75%+ in hosting costs • Owned REST/OpenAPI design and gated releases against agreed requirements • Drove stakeholder alignment on risks and priorities, and made key architectural decisions

Senior Software Engineer (Java/Clojure, Elasticsearch) at Kantar Media

• Built an Elasticsearch client in Clojure for indexing and search; improved text highlight accuracy; maintained the production media monitoring servers • Mentored junior team members and communicated with the project manager on issues, timelines and releases

Software Engineer (learning platform microservices, leaderboards) at CCS Digital Education

• Built event-driven microservices on Docker and Amazon ECS for a learning platform • Designed and implemented Redis-based leaderboards that improved and enhanced user engagement

Software Engineer (secure electronic voting optimizations) at Scytl Secure Electronic Voting

• Reduced memory usage by 80% and output size by ~60% on ballot-box exports using batched queries and gzip compression • Built validators to verify election configuration, digital signatures, certificates, and requests to the voting server • Onboarded and mentored two later team members to integrate successfully

Software Engineer (messaging integration, test coverage) at European Dynamics

• Delivered software on schedule, increased unit test coverage from 20% to 70%, refactored code to improve performance, and integrated asynchronous messaging across projects