What actually works for getting first customers for a B2B developer tool? Sharing what we're trying

We're 3 months into building a SaaS for iOS developers and just switched from building mode to selling mode. Zero paying customers so far, actively trying to fix that.

Posting here because I want to learn from people who've done this, not because I have answers.

What we're trying right now

Cold DMs on X to iOS developers who've tweeted about App Store review frustrations. Personalised, referencing their specific situation. Low volume, high effort.

Reddit posts in developer and founder subreddits. Leading with the problem, mentioning the product at the end. Better engagement than expected.

Commenting on relevant threads where developers are complaining about the exact problem we solve. Being genuinely helpful first.

Concierge outreach, emailing small iOS teams directly and offering to set up their first onboarding experiment for free in exchange for a testimonial. Haven't sent enough to know if it works yet.

What we haven't figured out

How to get a developer audience to trust a new tool enough to integrate an SDK. The evaluation cycle is longer than a typical SaaS, they have to actually add the SDK to their app before they can see any value.

Whether indie developers are even the right ICP or whether we should be targeting slightly larger teams from the start.

The honest situation

We built more than we should have before talking to customers. Classic mistake. Now we're trying to sell something that works but that nobody knows exists.

What's actually worked for getting first customers for a developer tool with no existing audience? Especially when the product requires SDK integration before the value is visible.

(Building at flwkit.com if context helps)