So we want to make the software open source, but restrict a few modules that would be necessary for enterprise customers, such as security and auditing features.
We have quite a few companies lined up that want to do proof of concept trials with us. So far they are mostly big fintech companies that use it for anti-fraud, also AML/KYC companies that need to match and search lots of data from different sources in real time. Also very large companies that need to solve their "data silo" problem.
Adoption - hopefully they start with the OSS version, play with then want to upgrade to the enterprise version.
One area we have less experience is with which type of OSS licence to use.
I see a lot of similarities between Kafka and Confluent. You're looking to spin out a tool that worked well for you, and offer it commercially.
I'd suggest planning more around operating TiloDB as a managed service. You happen to just need lambda, s3, and dynamo today, but the "capturable" value for many customers will be if you also manage it all for them (especially upgrades). You can still offer the open core and let folks run their own, but it sounds like a lot of the goodness comes from the way you run it.
Having said that, licensing is currently fraught in this space. Each major "database" vendor (Elastic, Redis Labs, Confluent) is basically trying to find a way to figure out how to avoid AWS (and other clouds) from just taking their code and operating it as a service.
People have very strong opinions on this topic, ranging from "open-source isn't a business plan" to "AWS is violating the spirit of the OSS community" and many more. My personal advice would be to assess more clearly why you want to be open source (you mentioned community and applications you couldn't imagine) and whether you think open source better achieves those goals than say a free tier or distributing a core binary / container image for free.
What, more specifically, do you want to get out of being open source? Contributions to the core? Contributions to the operational part? More users and feedback?
re OSS strategy - it's more users and feedback that I firstly think of. For instance, people keep telling us that there could be a really great use case in crypto compliance/auditing - tracking related wallet addresses etc. We don't really know enough about blockchain to validate that, but I think an OSS community could.
It seems to me that all the knowledge / experience of your staff is your real asset here, not necessarily the code. While that, in theory, should mean open-sourcing the code won't matter for your business, in practice it means you will be seeding competitors unnecessarily.
Turning your staff into highly chargeable consultants could be a more sustainable business model than trying to herd the cats of the internet into trying to improve your product offering, when most of those guys won't have the experience of your existing team. By offering the code out as open source you are giving a bunch of people a leg up and cutting short your time as the only game in town, which puts extra pressure on sales and might not work out.
Setting up a business based on a new DB tech that has one user, though, is tricky.
Playing devil's advocate, how do you plan to make money? Who are the users, why do they turn to TiloDB, how do they learn about it, how do they adopt it, how do they be convinced to pay you something for it? Etc