Isso

Isso – Ich schrei sonst – is a lightweight commenting server written in Python and JavaScript. It aims to be a drop-in replacement for Disqus.

Features

• Comments written in Markdown
  Users can edit or delete own comments (within 15 minutes by default). Comments in moderation queue are not publicly visible before activation.
• SQLite backend
  Because comments are not Big Data.
• Disqus & WordPress Import
  You can migrate your Disqus/WordPress comments without any hassle.
• Configurable JS client
  Embed a single JS file, 65kB (20kB gzipped) and you are done.