Senior full-stack software engineer
Database, API, infrastructure and interface — one pair of hands. So a feature ships as one thing, not as four handovers.
Self-employed 2020–21 · Incora 2021–25 · Geniusee 2025-2026
Lviv, Ukraine (UTC+2/+3) · Independent contractor — direct or via employer of record · Full overlap with EU & UK hours, US East Coast mornings to 1pm ET · Remote, or hybrid in Lviv · Notice 2–6 weeks · 9:00–20:00 Kyiv
01 · Cost
Route each request to the cheapest engine that can answer it, cache what has already been crawled, and make every model call traceable — so spend is visible per feature rather than as one line on a monthly invoice.
Where: AI search-visibility platform · 2025–26
02 · Revenue
Reporting and dashboards that the people paying for the product actually open: clinical PDF reports built in D3, and a real-time hardware state dashboard in Three.js for a security platform.
Where: Disease analytics · Hardware security platform
03 · Process
Integrations that reconcile on their own instead of ending in a spreadsheet someone maintains by hand: a CRM connected to storefronts, and event-driven statistics over Kafka on a building management platform.
Where: E-commerce infrastructure · Building management
04 · Delivery
Database, API, infrastructure and UI, so a feature does not queue behind three teams. Node.js and Nest.js on PostgreSQL, React and Next.js on the front, Terraform and AWS or GCP underneath.
Where: All of it
The core of the optimization engine on a platform that tracks how brands surface in AI search answers: routing each request to the cheapest engine that can answer it, caching what has been crawled, and tracing every model call.
Read →Back-end microservices for a security product watching a fleet of servers: ingest kept dumb and always available, bursty analysis split off behind it, live state pushed to the operator view.
Read →One D3 charting layer serving the interactive clinical views and the printed PDF reports from the same code, so a chart cannot say two different things.
Read →Write to me
penxerscky@gmail.comTell me which layers you need covered and the timeline. Use the form, or write straight to the address above.
Hours
9:00 — 20:00 Kyiv (UTC+2/+3), weekdays
Response
Within one working day
Engagement
Contract — direct or via employer of record
Send a message