Isso review 2026: an in-depth look at this self-hosted, open-source Disqus alternative for blog comments, its features, setup and top alternatives.
Isso fills a specific niche: giving blog and static site owners a way to accept reader comments without routing visitor data through a third-party advertising and analytics company like Disqus. It runs as a small, self-hosted Python server paired with a lightweight JavaScript widget that any site can embed, regardless of what the rest of the site is built with.
The project was created by developer Martin Zimmermann, known online as 'posativ,' originally to serve his own blog's needs, and has since been carried forward by the open-source community, with the codebase now maintained under the isso-comments GitHub organization. It has no corporate backer and no paid tier; it is simply a free, open-source tool maintained by contributors.
Isso is particularly popular among users of static site generators such as Jekyll, Hugo and Pelican, which have no native way to accept dynamic comments and would otherwise need to rely on a hosted third-party widget.
At its core, Isso is a Python server backed by SQLite, meaning every comment, reply and moderation decision is stored in a single local database file the site owner fully controls, with no data ever leaving their own server. The accompanying JavaScript client is intentionally minimal, at roughly 65KB uncompressed, keeping page weight low compared to most hosted comment widgets.
Isso supports Markdown formatting in comments, lets commenters edit or delete their own submissions within a configurable time window (15 minutes by default), and gives site administrators a moderation queue to approve, reject or remove comments before or after they go live, helping control spam and abuse without an external moderation service.
To ease migration away from hosted platforms, Isso includes built-in importers for Disqus and WordPress comment exports, so site owners switching away from a third-party service can bring their existing comment history along rather than starting from zero.
Isso itself is entirely free and open source under the MIT license; there is no license fee, subscription, or paid tier of any kind, since the project has no company or commercial arm behind it. Anyone can download the source from GitHub or install it via PyPI at no cost.
The only ongoing cost is whatever server infrastructure an operator chooses to run it on, since Isso must be self-hosted rather than used as a managed cloud service. In practice this typically means a small virtual private server or Docker container costing a few dollars a month, a fraction of what a hosted comment platform with a paid tier would charge, especially for sites with any meaningful comment volume.
Isso is a lightweight, self-hosted commenting server written in Python that serves as an open-source, privacy-friendly alternative to Disqus.
Yes, Isso is completely free and open source under the MIT license. The only cost is the server infrastructure needed to self-host it.
Isso was created by developer Martin Zimmermann (GitHub handle posativ) and is now maintained by the open-source community under the isso-comments GitHub organization.
Yes, Isso includes built-in import tools for migrating existing comment threads from Disqus and WordPress.
Yes, Isso is commonly used with static site generators like Jekyll, Hugo and Pelican, which have no native commenting system of their own.
Isso stores all comments locally in a SQLite database, keeping all data on the operator's own server.