Andrejs Eisaks

Andrejs Eisaks

Staff Software Engineer | Backend & Distributed Systems

Building reliable, scalable systems that solve real problems

About

I'm currently a Staff Software Engineer at AtoB, working on backend systems for fuel card products and financial infrastructure. Over the past 10+ years, I've built distributed systems, led engineering teams, and shipped products across multiple startups—from peer-to-peer carsharing to PropTech to visual testing platforms.

My journey with technology started early—at age 6, thanks to parents who both studied computer science. By 16, I was running an MMORPG server with 700 concurrent players, learning about databases, uptime, and what happens when systems fail. That early fascination with building things from nothing never went away.

I moved from Latvia to Switzerland in 2011 for love, and it turned out to be one of the best decisions of my life—both personally and professionally. Since then, I've worked across civic tech, mobility, real estate, and fintech, always gravitating toward the hard problems: scaling backend systems, improving async architectures, and making legacy codebases more reliable.

I believe in building non-toxic, collaborative engineering cultures where modern practices thrive. I've learned the hard way that technically elegant code only matters when it's aligned with real product needs. These days, I'm most interested in systems that are simple, observable, and genuinely useful—not just clever. Outside of code, you'll find me alpine skiing, hiking, or experimenting with photography.

Experience

Staff Software Engineer

AtoB

Oct 2024 - Jun 2025

Backend engineer for Customer Retention team working on fuel card products, pricing systems, and telematics integrations.

  • Designed flexible discount agreement system supporting multiple pricing strategies across partners
  • Improved telematics integration stability with bidirectional sync and IFTA reporting
  • Built geo-fenced fuel site access system and loyalty incentive engine under tight deadlines
  • Owned production-critical systems handling real-time fuel purchase data

Senior Software Engineer

Rainforest QA

Oct 2023 - Sep 2024

Backend engineer on visual no-code testing platform, focusing on stability, AI features, and infrastructure migrations.

  • Led migration of async job processing from QueueClassic to GoodJob, reducing PagerDuty incidents
  • Implemented AI-driven test recovery and Playwright test generation features
  • Built internal tooling for reviewing and improving AI agent prompt quality
  • Optimized legacy distributed system for browser automation and test execution

Engineering Manager

Crowdhouse AG

Sep 2021 - Mar 2023

Led platform team (4-6 engineers) while managing 9 engineers across organization. Architected PropTech MVP and infrastructure.

  • Built AWS processing pipelines ingesting and distributing payout data to thousands of investors
  • Conceptualized and led PropTech product development in MVP phase
  • Reduced manual payout processing from hours to minutes through automation
  • Responsible for technical recruitment, onboarding, and engineering culture

Lead Software Engineer / Technical Lead

Crowdhouse AG

Oct 2018 - Sep 2021

Established and led platform team, driving migration from monolith to microservices architecture.

  • Led migration from monolithic application to microservices-based distributed system
  • Introduced DevOps practices (CI/CD, IaC, Monitoring) across engineering organization
  • Built Ruby on Rails SSO service for seamless user migration and cross-app sessions
  • Implemented React-based CMS for real estate deal and user management

Technical Lead

sharoo AG

Oct 2016 - Jul 2018

Led product team of 4 engineers on peer-to-peer carsharing platform with hardware integration.

  • Built scalable telemetry service consuming car hardware data via persistent connections
  • Replaced unstable legacy solution, dramatically improving stability and reducing on-call incidents
  • Developed notification service using AWS SNS, SQS, and Redis for high-volume user engagement
  • Mentored junior engineers while maintaining production reliability

Skills

Expert

Technologies I use daily and have deep production experience with

Ruby & Ruby on Rails
10+ years, built dozens of production systems
Backend Architecture
Designed microservices, async systems, and distributed infrastructure
PostgreSQL
Query optimization, schema design, and performance tuning
AWS
Lambda, S3, DynamoDB, EventBridge, SQS — production at scale

Proficient

Strong working knowledge, use regularly in production

TypeScript & Node.js
Built APIs, processing pipelines, and internal tools
React & Next.js
Full-stack development when needed
Docker & Kubernetes
Container orchestration and deployment
Redis & DynamoDB
Caching, session storage, and NoSQL data modeling
System Design
Distributed systems, async architectures, and scalability

Currently Exploring

Learning and experimenting with

Go & Rust
Performance-critical services and CLI tools
Python & Machine Learning
ML fundamentals, data analysis, and their applications in backend systems
AI/ML Integration
Prompt engineering, AI-assisted development
Event-Driven Architecture
Real-time data pipelines and streaming

Now

// Working On

Exploring new opportunities in backend engineering and distributed systems. Open to staff/senior roles where I can have technical impact.

// Learning

Deepening my understanding of Go and Rust for performance-critical services. Exploring machine learning fundamentals and their applications in backend systems. Learning German. Experimenting with AI-assisted development workflows and prompt engineering.

// Reading

Currently revisiting "Designing Data-Intensive Applications" by Martin Kleppmann and exploring papers on distributed consensus algorithms.

// Open To

  • Staff/Senior Backend Engineering roles with distributed systems focus
  • Technical mentorship and architecture discussions
  • Contributions to open-source infrastructure tools

// Last updated: November 2025