Show HN: DrawDB – open-source online database diagram editor (a retro)

What you have built can definitely become a product supporting you with a very nice income. Free version can stay free but you can sell solo licenses and team licenses as subscriptions. Paid license users will also have your support - and that matters to companies.

As others have said, commercial features can be built on top of the OSS product, like Electron desktop client, support for more databases, for views/procedures etc.

There is no downside to trying to commercialize this. Whoever wants to use what you have built so far can continue and I guarantee that many companies would be happy to give you $50/month for a more advanced version with support.

(edit for typo)

I know lots of people in the FOSS community who would stop using it as soon as you "sold out"... but those people probably don't represent the majority of potential users.

Monetization of a GPL or AGPL project generally involves a CLA so that the creator can offer closed-source and/or SaaS enhancements while still accepting third-party contributions. Without a CLA, the project creator would be violating the copyright license that was granted by the third-party code contributors. He/she doesn't own their code and cannot relicense it in a way that violates the AGPL.

Selling out is relative to having one's living costs somehow subsidized.

Not everyone has the same financial safety nets, and likely most have to create a safety net for themselves.

Maintaining a clear line between the free size and paid should be easier here compared to other tools should the developer decide to go that way.

People start something with good intentions, then the project grows to the point where it requires a lot of unpaid time, and there are expectations from the users. There are bills to pay and limited time in a day.

I would probably be irked if I contribute in my free time and then see my effort being used in a commercial product. Then again, in some products you may have one person doing 95% of the work and another 50 doing 5% of the work.

If OP is motivated, they can relinquish control over this project and start a completely new one from scratch with no code borrowed from the existing one but learnings can definitely be applied. The new commercial project would need to compete with the existing AGPL project - and that's a good thing. If 60 contributors are contributing significantly, FOSS project won't suffer and the OP will be able to live from something they are passionate about.

Selling services like support or consulting is fine, since that's generally independent from FOSS licensing/copyright concerns. Anyone can do that though, not just the creator or contributors. For example, there are lots of third party database consultancies that offer support for major databases, both FOSS and commercial.

Customization is also fine, but the purchaser of the customization must still abide by the AGPL: the end-users of the customized software need access to the customized codebase. If the customized product is only being used internally (e.g. for employees of the company that purchased the customization) then there's no problem. But if they're offering it in an externally-facing SaaS, or embedding it in externally-distributed software, the customized code must be made available to the end-users of the software.

With FOSS often it's simpler to do this as "sponsored development" where someone pays for a new feature to be made directly upstream, rather than having a customized fork.

That all said, services and customization are generally difficult to scale as a business. Even with a fairly large userbase, the percentage of companies who are willing to pay for support or customization tends to be disappointingly low.

Or here’s another route: sell “licenses” regardless of the actual license. I think https://cyberduck.io/ has this: you can donate and get a key that removes the donation nag. If you do this, you can’t go after the pirates, but would you really want to spend your time on that? (Of course, I would still reach out to the contributors first, explain the situation and see if they are okay with all that.)

Good luck to the OP!