Don't know where to start?

activitypub.rocks/ is an excellent place.

They also have forums with massive amounts of helpful folks: socialhub.activitypub.rocks/

I'd also recommend Matrix! The Fediverse Developer's Network has some of the best folks actively working on AP software and they're all super friendly and coming.

matrix.to/#/#fediverse-devel...<span class="invisible"> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/ActivityPub">#ActivityPub</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/Fediverse">#Fediverse</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/Developers">#Developers</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/FFOSS">#FFOSS</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/FOSS">#FOSS</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/Matrix">#Matrix</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/Forums">#Forums</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/Discourse">#Discourse</a> <a class="hashtag" rel="tag ugc" href="https://btfree.social/hashtag/software">#software</a>
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