Building a business around open-source software

The code stayed free.A business grew around it.

I build Dawarich, an open-source location history app anyone can run for free. FOSS to SaaS is a finite letter about the decisions, mistakes, and numbers behind the business that grew around it.

Fifteen issues · roughly weekly · then it stops

The ledger

Stars on GitHub: 10,000steady growth, no overnight success
People registered: over 10,000all time
Self-hosted instances: over 5,000for the past year
Location points stored: over 150 millionone Postgres, two servers
Contributors: 65and counting
Years running: 2since 2024
Still free and self-hostable: Yesthe entire point

I don’t publish revenue figures. The rest of it I can show you: conversion, churn, traffic, how many people ever import their data.

Who is writing this

I’m Evgenii Burmakin. Eugene to almost everyone. I live in Berlin and I have a day job writing Ruby, so Dawarich has been an evenings-and-weekends thing since 2023.

It started because Google Timeline lost several years of my location history. I wanted the data back and I wanted it on a machine I owned. That turns out to be a common complaint. The repository has over ten thousand stars now and more than sixty people have contributed code to it. In 2025 my co-founder and I registered a UG in Germany. He runs the mobile side.

The project is still free, and I’m not planning to change that. You can clone it today and run it on a box in a cupboard without ever sending me anything. The paid side has to work with that still true. I answer most of the support mail myself.

None of it is finished, which is most of the reason I’m writing it down now instead of in five years, once I’ve had time to tidy up the parts that went badly.

Built: Dawarich, an open-source location history app. AGPL, self-hostable
Based in: Berlin, since 2022
Day job: Senior Rails engineer, at a company that is not this one
Spoke at: Geomob. The talk won a prize
Featured on: Linux Unplugged, a few times

dawarich.app github.com/Freika/dawarich

Why I am writing this

The question I get is never how the thing is built. It’s how you get anyone to pay for software they can legally download and run on their own hardware without paying you. I’ve been asked it after every talk I have given, and twice at the same conference dinner.

For a long time my answer was bad. Three years of decisions did exist, but they lived in my head and in Telegram messages to my co-founder, which is not a form anybody else can use.

There is a lot written about running an open-source project, and more than enough about running a subscription business. The join between them is thinner. How do you price something that is also free? I kept one component closed and had to explain that to an audience with every right to be annoyed about it. I registered a company in a country whose tax code I did not grow up with. I answer support mail on Sundays, because the person who sent it is the reason there is a business at all.

I took notes the whole way through. About fifteen of them seem worth sending.

What this is, and what it is not

It is

Fifteen issues, roughly weekly. Then it stops.
One project followed the whole way through. It’s free to self-host and it still has to pay for itself.
Decisions with the outcome attached, including the ones that went nowhere.
Written while it is still going on, so I will be wrong about some of it in public.

It is not

Free, with no paid tier at the end. Nothing is being set up for issue fifteen.
Not neutral. It is my own company and I have every reason to make it look better than it was.
Not a universal recipe. A location-history app for developers is one shape of business; yours is likely another.
Not a full open book. I don’t publish revenue figures and that isn’t going to change.

The fifteen letters

Written in order, sent about a week apart. Each one is a decision I had to make anyway, and what came of it.

The two-product splitWhat stays free forever, and what people actually pay for.
Pricing a thing that is also freeHow I set the number, and what happened the day I put it up.
Getting paid across bordersWhat registering a company abroad involved, and who handles the VAT.
Where the first thousand users came fromReddit first, then a podcast picked it up, then a talk.
Rewriting the page that sells itWhat happened when I applied an offer framework to a free product.
The activation cliffFour out of five people who sign up never load any data in.
Free trial, reverse trial, no trialThe day we stopped having free users at all.
Reading churn without flattering yourselfWhat I found after emailing the people who left.
Support at ten thousand starsWhich questions to answer once and which to document properly.
Saying no in publicOne component stayed closed, and how I explained that.
One person, one production databaseMore than 150 million location points in one Postgres, with no ops team.
Contributors, sponsors, and the lineHow much goodwill a project has, and what spends it.
Sponsorships, affiliates, donationsThree revenue experiments, and how far each one got.
The dashboard I built to stop guessingMeasuring the funnel when nobody hands you one.
What I would do differentlyThe things I would skip if I started again this week.

Who this is for

Write to me if

You maintain something people actually use and it makes no money.
Raising money is not the plan.
You want to see the numbers behind a decision.
You are not in a hurry. This has taken three years so far.

Do not bother if

You want a launch trick that works this month.
You think open source is a business model on its own.
You are looking for a licence that solves it.
You have not shipped anything to a stranger yet.

Before you decide

How often will you write?

Roughly weekly, though a release week will push it. Fifteen issues and then it is finished. I don’t want to run a newsletter indefinitely; there is a specific subject here and it runs out.

Is it free?

Yes. There is no paid tier and no course at the end of it.

Do I need to use Dawarich, or even care about it?

No. It is the example I happen to have. Whether any of it transfers to your project is something you will have to judge as you read.

Will you show real numbers?

Most of them. Conversion, churn, traffic, how many signups ever import anything, what a given channel returned. Not revenue.

What happens to my email address?

It goes to a mail server I run. I don’t rent the list out and there is no tracking in the emails. Every issue carries an unsubscribe link.

When does the first issue arrive?

I don’t have a date. I would rather not fix one now and then miss it in the first week.

Fifteen letters, and then it stops

No date for the first one yet. Join the waitlist and I’ll send it when it is written.