Directory
Discourse
Open-source forum platform
Free tier + paidRealtime, comments & collabdiscourse.org
What it is
Mature open-source discussion platform with categories, trust levels that grant moderation powers as members participate, a genuine moderation toolkit, full-text search, reply-by-email and a large plugin ecosystem. Ships a comment-embed mode that mirrors blog post comments into forum topics through a single script tag.
Why it earns a slot
The serious answer when comments should grow into a community rather than stay a per-article afterthought. Embed mode gives you article comments today and a full forum later without migrating any content.
Know before you commit
It is a Rails app needing Postgres, Redis and Sidekiq, so self-hosting is real sysadmin work and the official floor is a 2 GB VPS. Communities also need active human moderators — trust levels reduce that burden but never remove it.
Getting started
Run the official Docker discourse-setup script, or use hosted
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Ably
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Agora
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Chatwoot
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Circle
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