Fullstack Engineer & Founder
Timo Kilpilehto
16 years building software end-to-end — from architecture to deployment, frontend down to the infrastructure underneath. Hire me as a one-person team to take an early product from zero to one, or as a senior fullstack developer who joins your team and hits the ground running.
Along the way: Java Card applets, wearables, smart TVs, phones and tablets, large-scale ad systems, and the modern web and AI stacks I build with today.
About me
Senior engineer with 16 years across the full stack — and most of the layers above and below it. I've worked on just about everything: Java Card applets, wearables, smart TVs, phones and tablets, large ad systems, and the web and AI tooling I use day to day.
I've co-founded startups, won a few hackathons, and spent years as a senior developer on a small, tight team behind revenue-critical infrastructure. Since March 2025 I've run Shieldgrove, taking on engineering work I can see through from design to deployment — as a one-person team for founders, or embedded in an existing team.
I'm based in Helsinki, where most of my free time goes to my family. What's left tends to get spent on committees: I chair my housing company's board, sit on another, and serve on a local school board.
Find me online:
How to work with me
1 —
A one-person engineering team
For founders and early-stage teams.
Take a product from nothing to shipped: architecture, build, and the pipeline to deploy it — by someone who's done exactly that before, solo and from scratch. A fractional CTO or founding engineer, without the headcount commitment.
2 —
An embedded senior developer
For scale-ups and established teams.
An experienced fullstack developer who slots into almost any team and hits the ground running — no long ramp, no hand-holding. Happy to take responsibility for a hard, critical system, and at home across TypeScript/Node, Vue, Flutter, and the backend and infrastructure behind them.
3 —
Hardware, embedded & cryptography
For the problems most developers won't touch.
When it isn't a standard web stack — secure elements, NFC, smartcard applets, offline-first systems with cryptographic integrity, tight embedded memory budgets. Niche work, done properly.
Work experience
Founder
Shieldgrove, Helsinki
Mar 2025 – present
Running my own consultancy, taking on projects from design to deployment. Built the Tehoäly AI-assisted grading MVP from scratch for Teho-opisto; took elton.coach to a commercial milestone with a focused Flutter sprint; built a custom Learnworlds checkout with Zapier-orchestrated invoicing.
Founder & CIO
Digizen
Aug 2018 – 2025
Co-founded a distributed digital identity system for populations without prior ID — NFC-based, field-deployed in Papua New Guinea with the Bank of PNG and microfinance institutions. Sole architect across the full stack: Java Card applet, two offline-first Flutter apps, Java backend, JavaScript admin dashboard, AWS infrastructure. Manufactured and shipped 20,000 cards.
Senior Software Engineer — Feeds
Smartly.io, Helsinki
Apr 2018 – Feb 2023
Senior IC on the Feeds team powering Dynamic Ads — then the company's top revenue line. Owned systems processing customer product catalogs in the hundreds of millions, syncing to Facebook, TikTok, Pinterest. Built automatic feed-field mapping in TypeScript, redesigned the scheduling UX, contributed to the Kotlin + Elasticsearch catalog service.
Co-founder
Geasy — Hackathon Collective
Jan 2015 – present
Recurring hackathon team with a strong track record: Hibbo (children's connected piggybank, €50k prize), Geasy speedreading watch (Samsung challenge, €5k), Seutuseikkailu (AR transit app, winner), eid.asia (ADB/AIM Manila winner — became Digizen). Slush Smackdown educational coding game deployed on JCDecaux panels across Helsinki.
Senior Developer
AppGyver, Helsinki
Sep 2016 – Mar 2018
Worked on a Node-RED-based visual programming and execution engine. Owned containerisation and infrastructure migration from Heroku to GCP using Terraform and Kontena. Ruby backend, custom JavaScript node blocks for enterprise customers.
Senior Developer
Iwa Labs (now OIVAn), Helsinki
Oct 2010 – Aug 2016
First professional role — six years of client-project work across webapps, APIs, Android mobile apps, Android TV customisation, and Ruby on Rails backends. The breadth and depth that made everything after possible.
Education
BSc, Computer Science
University of Helsinki
2005 – 2010
Skills
Selected work
Digizen
Digital identity for the unbanked
Problem:
Millions in Papua New Guinea have no formal ID, shutting them out of banking and microfinance. Connectivity is unreliable, so the system had to work fully offline and reconcile later.
What we built:
I co-founded Digizen and was its architect, working across the whole stack alongside my colleagues — a Java Card applet running under hard memory limits with no garbage collector, two offline-first Flutter apps (enrolment and verification), a Java backend, a JavaScript admin dashboard, and the AWS infrastructure. Offline-first state model with a signed-payload chain and conflict-aware sync.
Result:
Field-deployed with the Bank of PNG and several microfinance institutions. 20,000 NFC cards manufactured, programmed, and shipped.
Smartly.io — Feeds
Ad-platform product feeds at scale
Problem:
Dynamic Ads was Smartly's top revenue line, built on customer catalogs in the hundreds of millions — feed files up to ~30 GB — that had to sync reliably to Facebook, TikTok, Pinterest and others, each with its own quirks.
What I did:
As one of the most senior developers on the Feeds team, I knew the codebase inside out and took responsibility to ensure synchronization worked reliably and efficiently. Additionally, to name a few contributions of mine: automatic feed-field mapping, a scheduling UX redesign (drifting sleep intervals → a user-shaped pick-time-and-cadence model), Liquid template support for multi-field expressions, and the Kotlin + Elasticsearch catalog service.
Result:
Reliable syndication across the major ad platforms, underpinning the company's leading revenue line.
Let's work together
Have a product to build, or a hard system that needs a steady pair of hands? I take on contract engagements and longer-term roles — as a one-person team or embedded in yours. I'm available flexibly now, with room for bigger commitments opening up later in the summer.