Fullstack developer

Father · Builder · Ultrarunner

Fullstack GIS developer at Sitowise — PostgreSQL/PostGIS, Java/Angular, React, .NET / C#, React Native. Master's thesis (2026) on privacy-first local LLMs - a few degree points still open. Based in Turku.

Kalle Tolonen mugshot

CONTACT & REFS

Recent Articles

Kids these days - where do you take them?

2026-10-01

My son is about to turn into a toddler. One of the questions I have pain answering is "what to do this weekend or today to keep him entertained?". The information exists and you could just ask AI like a sane person. So naturally I built a serverless side project.

It has a selected list of playgrounds nationally and LLM-curated events in the 15 biggest cities, on a map with travel times shown as an isochrone map per mode of transport. So, we're basicly answering the question "What current or future fun thing can I reach with my kid in 5/15/30 minutes by walking/biking/driving".

I do realize that there's serious overlap with Leikkipuistot.com, but we throw isochrones and events on top, and we're not using cookies.

This week in Turku within 15 minutes of driving

Try it out at: Muksukartta (iPhone location perms hss been buggy, and hard to fix without an actual iPhone, so sorry if it still has problems!)

Taste is not the err in human input

2026-09-22

Agents and swarms of agents are quite nifty nowdays. My current setup is simple. It runs a coordinator that I communicate with, and that delegates work to a others. The flow is generally: "Hey, I need this feature from roadmap. Ask questions if needed, if I don't answer in due time, make the best call with our north star." -> Coordinator makes a plan for dev/qa -> dev devs -> pushes to branch when tests are green -> qa verifies results on dev server -> loopy-loop until obvious bugs are fixed. Review bot makes review for PR. Later on I test the feat to see if it's anything like I wanted and correct, then merge when good and pool to releases that are gated. Currently working on trying to get the agents to know what is good in my opinion.

I think the current killer combo is the ability to be creative and have some propriatory data, as that's something that can't be accessed by competition. The cost of iteration is low. So low that I see no point in using a wireframe demo for the ui, as simple paper sketches can be read by AI to close enough for live iteration for actually working software. And most rigid general UI's are going away too in favor of agents generating a personalized UX on the fly, so this is just temporary. Omarchy is the beacon for this, a machine that is ever evolving to your needs.

The stuff that stays valuable is hard to automate - having taste, accountability, human relationships and even defining what is good. No one knows what the future will be, but it will be awesome.

Futurama

Building an MCP bridge

2026-09-16

MCP was not clicking for me, so the best way to learn was to build a thing with it. I have a plethora of notes everywhere and now I have a machine that drops rough ideas into my publishing backlog.

MCP is basicly an api for AI that tells agents how it's supposed to be used.

I didn't know what to build, so I made scaffolding

2026-09-15

Building an app factory, that utilizes Cloudflare's free tier resources to have quick and dirty apps to demo.

Agentic hangover

2026-09-11

When you can do whatever you want to do, what do you want to do? I'm personally not so sure, since most of the problems in my world have been solved. On the other hand, you don't know what you don't know.

Public Refs

Muksukartta phone map: Helsinki playgrounds and event pins inside a walking isochrone

Muksukartta

Muksukartta (2026). Travel-time map for kids.

  • Finnish kids POI PWA with isochrone/travel-time maps
  • React + Leaflet
  • ETL for open-data / event feeds
  • Applied LLM for event parsing
kalletolonen.com reference photo

Maritime

Architected an automated spatial analytics pipeline for live AIS vessel tracking over MQTT - ported key ingestion paths to Rust, cutting processing time by an order of magnitude. (2026)

  • Live AIS vessel tracking for the Baltic Sea and coastal Finland
  • Tap a ship for metadata, speed/heading, and its recent track on the map
  • Forms automated GIS-based analysis of vessel data
Superlatiivit.com reference photo

Superlatiivit.com

Data mining & processing (2024)

  • Mines Finnish Wikipedia for superlatives and handles suffix exceptions
  • Publishes three randomized adjectives each day
paiste.fi reference photo

Paiste.fi

Front-End with Bootstrap (2021)

deftle reference photo

Deftle

Python Wordle clone with word definitions (2022)

  • Wordle-style guessing with hand-built word data and logic
  • Shows the definition right after a successful guess