Dev tooling SAAS startup here, who should I target first?

I have created a passwordless/biometric authentication startup OnzAuth https://tryonzauth.com targeted predominantly at developers. I want to solve the problem of the repetitive, complex, time consuming task of adding a login to a new project every time and let them focus on other more important stuff. Of coz in my pipeline, I want to do the same to Payments, Memberships, Chats etc... ultimately creating a Twilio-like service for the user-centric kind of features mentioned above. My business subscription model atm is based on no. of active users logging in, with a free tier, flat rate per month + overages charges should the number of users be exceeded.

I have some dev users from my forums/connections using it atm, but now I am trying to get some traction and revenue if possible, a Beta launch, ProductHunt launch, trying to learn some marketing, and having conflicting thoughts on the strategy so far.

One thing I realized after targeting developers is that they are usually not paying customers, the worst kind of target persona in a sense. That got me thinking, how should I position my marketing strategy?

I think my product is most suitable for these personas atm

• Indie hackers (Independent creators, publishers, educators, podcasters, and gig economy)
• Developers
• Startup Founders, ideally more B2C centric kinda solution
• e-Commerce creators (Shopify Users)
• Dev Houses / Agencies

Long term, I want it to be an enterprise product in a way if I grow big enough.

My Current Marketing ideas

• I am thinking of partnering with Dev houses to push out my product to their clients as a potential strategy, so would need to market to them.
• Also, am looking at targeting startup forums and accelerators (offers, discounts) for new startups founders wanting to POC/MVP and product.
• ProductHunt, AppSumo launches
• Hackathons ???

Any advice on where I should really begin to target?