Martin Olsansky
About me
I have 10+ years of experience as a full-stack software engineer, across cybersecurity, banking, fintech, video platforms, marketplaces and healthtech.
Co-founded a company (seasy.com) that raised 7-digit funding. We worked with ESA (European Space Agency), joined their innovation incubator and went through YC Startup School. We got to hire and work with some great people. We made money, put food on the table, and made our customers' lives easier.
Gave lightning talks about TS, JS and React, and co-organised events on biotech and biohacking. Did a bunch of Startup Weekends, and was a core member of a local hackerspace. Wrote some tech articles and contributed to open source.
Mentored aspiring software engineers (nodeschool.io) and entrepreneurs (growni.sk).
Contact
Motivation
It matters to me that everyone's ideas get heard, and that the work is actually useful to someone. A clear goal helps. It gives me something to work towards. So does having time to get better, and to help others get better. I like working with people who keep their promises, have skin in the game, and keep things out in the open, so nobody's left guessing.
Time zones
Working remotely from the EU.
8AM EST is 2PM CET for me.
That's 6 hours of overlap.
8AM PST is 5PM CET for me.
That's 4 hours of overlap.
See more at worldtimebuddy.com.
Experience
NordVPN
The most popular VPN service. It encrypts your internet traffic. A unicorn with a $3B+ valuation and tens of millions of users.
Staff Software Engineer
- Developed browser extensions for Chrome, Firefox and Edge, used by tens of millions of users
- Built the extensions following the SSDLC (Secure Software Development Lifecycle) framework
- Kept improving the product, which raised our ratings in the extension stores. This directly increased subscriptions and revenue
- Ran A/B/n tests and used remote config to try out changes and roll out features to tens of millions of users
- Mentored junior team members and helped them grow
- Conducted hiring interviews
- Improved DX (developer experience) and made our development workflow faster and simpler
- Took part in design and UX discussions and gave feedback that improved the product
- Worked on cross-team projects, shared knowledge and helped align goals between teams
- Collaborated closely with the legal and AppSec teams
- Implemented VPN/proxy detection
- Debugged many low-level issues (e.g. proxy authentication, where I had to dig into the Chromium and Firefox source code)
- Helped set up our automated QA
- Prototyped internal test and lab projects, working closely with the R&D team
Seasy
A marina booking platform with 1,500+ sailing destinations around the world. Sailors can book marinas right from their yacht.
Tech Co-Founder
- Raised 7-digit funding and generated revenue
- Worked with ESA (European Space Agency), joined their innovation incubator and went through YC Startup School
- Hired and worked with some great people
- Made our customers' lives easier and safer
- Designed and implemented the architecture for services such as User, Search and Discovery, Booking, Messaging, Reviews, Notifications, Managing, Support, Backoffice, Payments and Refunds
- React Native (Expo) apps, a React SSR frontend and a federated Apollo GraphQL server with Postgres
- Acted as a forward-deployed engineer, visiting marinas to help them integrate their systems with Seasy
- Sometimes did customer support myself, to better understand our customers' journey and experience
Erste Bank
George is a white-label banking frontend for all banks acquired by Erste Bank. It is used by tens of millions of people in more than 6 countries in Europe.
Senior Frontend Engineer
- Incrementally refactored the legacy codebase from Marionette/Backbone.js to React, Redux and TypeScript
- Built and maintained key features such as plugins, transactions, chat, import and export
- Worked under strict banking security regulations
- Took part in grooming new features
- Did regular code reviews for other developers
- Pushed for TDD, knowledge sharing and a better bus factor
SaferPass
A password manager browser extension that securely stores and autofills passwords, passkeys, credit cards, notes and more. SaferPass was acquired by F-Secure.
Full-stack Software Engineer
- Developed the browser extension for 4 different browsers, and a build system to automate it
- Implemented and maintained sync of encrypted data across multiple devices
- Worked on automatic conflict resolution and upserting (not CRDT/Automerge, but PouchDB)
- Handled edge cases such as merging encrypted data from devices that were offline for a long time, and versioning encrypted data
- Developed the Android and iOS apps
HomeCredit
Internal tools for insurance and loan projects.
Senior/Lead Frontend Engineer
- Designed and implemented a micro-frontend architecture with single-spa
- Deployed to k8s via Helm
- Worked closely with Java backend developers
- Collaborated across multiple countries and time zones with many stakeholders
- Mentored junior developers
Treeti
Treeti is a streaming provider that offers a wide range of movies and TV shows in various genres and languages.
Full-stack Software Engineer
- Will add later...
Tech stack
Apps
browser extensions•electron•tauri•react-native•expo•
Languages
typescript•javascript•SQL•python•Cpp•Go•
Frontend
react•vite•tailwind•relay-gql•next.js•redux•vue•zustand•jquery•
Backend
node.js•express•graphql•TRPC•ORPC•OpenAPI•websocket•mqtt•
Database
postgresql•mongodb•supabase•firebase•redis•sqlite•cloudflare d1•
DevOps
docker•kubernetes/helm•netlify•aws•gcp•firebase•cloudflare•
QA / Testing
human code reviews•playwright•puppeteer•jest•fuck around -> find out (scientific method)•fuzzing•defensive programming•
Tools
llms•ai agents•rag•
Articles
Certifications
