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Comparison · Collab
Calibre-Web vs SiYuan
A side-by-side editorial comparison of Calibre-Web and SiYuan — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:self-hosted
Calibre-Web vs SiYuan: at a glance
What is Calibre-Web?
A yearly release cadence spent almost entirely on Kobo sync and self-hosting hardening.
Calibre-Web is a self-hosted web frontend for an existing Calibre ebook library. It ships roughly one consolidated release a year, each a large bundle in which a short new-feature list sits on top of a much longer set of bug and security fixes. The most recent releases added MOBI and audio metadata extraction on upload, reverse-proxy login via a shared secret header, multi-book editing, and Calibre 9 compatibility. Kobo e-reader sync absorbs a disproportionate share of every release.
What is SiYuan?
SiYuan stabilises 3.8.1 after a seven-build beta run, all of it widening the agent surface it opened in 3.8.0
SiYuan has just cut 3.8.1 stable, the endpoint of a beta chain that ran six builds in five days. The release groups into three areas: AI integration work - custom editor actions syncing across devices, an Agent panel shortcut, user-level skills read from a shared agents directory, nested rerank API formats and OpenAI Responses API support; editing and database throughput, including virtualised grouped-table rendering and faster document loading; and cross-platform reliability covering HEIF/HEIC previews, PDF export and mobile behaviour. A batch of MCP and publishing-service fixes rounds it out.
Calibre-Web vs SiYuan: editorial side-by-side
Calibre-Web
2.5COLLAB
A yearly release cadence spent almost entirely on Kobo sync and self-hosting hardening.
◆ Current state
Calibre-Web is a self-hosted web frontend for an existing Calibre ebook library. It ships roughly one consolidated release a year, each a large bundle in which a short new-feature list sits on top of a much longer set of bug and security fixes. The most recent releases added MOBI and audio metadata extraction on upload, reverse-proxy login via a shared secret header, multi-book editing, and Calibre 9 compatibility. Kobo e-reader sync absorbs a disproportionate share of every release.
◆ Where it's heading
Development here is maintenance-shaped rather than expansion-shaped, and the shape is getting more pronounced: 0.6.27 lists two new features against roughly thirty fixes, where 0.6.25 a year earlier listed close to twenty additions. The sustained investment sits in two places — keeping Kobo sync working against a vendor API that keeps moving underneath it, and making the app behave correctly behind reverse proxies and in container deployments. Compatibility work with current Calibre and current Python versions is treated as release-blocking, which is the right read for a project whose value depends entirely on staying installable.
◆ Prediction
Given the cadence, expect the next release six to twelve months out as another consolidated bundle led by Kobo sync repairs and Python or Calibre compatibility work rather than new capability. Reverse-proxy authentication is the one area with visible recent momentum, so further authentication-integration options are the most plausible genuinely new addition.
SiYuan
6.3COLLAB
SiYuan stabilises 3.8.1 after a seven-build beta run, all of it widening the agent surface it opened in 3.8.0
◆ Current state
SiYuan has just cut 3.8.1 stable, the endpoint of a beta chain that ran six builds in five days. The release groups into three areas: AI integration work - custom editor actions syncing across devices, an Agent panel shortcut, user-level skills read from a shared agents directory, nested rerank API formats and OpenAI Responses API support; editing and database throughput, including virtualised grouped-table rendering and faster document loading; and cross-platform reliability covering HEIF/HEIC previews, PDF export and mobile behaviour. A batch of MCP and publishing-service fixes rounds it out.
◆ Where it's heading
This is consolidation of the surface 3.8.0 opened, not an extension of it. The agent, semantic search and MCP endpoint arrived in the 3.8.0 line; 3.8.1 makes them portable and pluggable - skills come from a directory the user controls, editor actions follow the user between devices, and the provider layer now speaks the OpenAI Responses API rather than one bespoke shape. The high beta count against a modest final diff shows a project stabilising a young subsystem rather than building a new one.
◆ Prediction
The next line most likely pushes on the skills directory - discovery, sharing or marketplace distribution of user-level skills - since that is the piece 3.8.1 made user-editable without giving it a distribution path.
Alternatives to Calibre-Web and SiYuan
Other Collab products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Calibre-Web or SiYuan.
Read the Docs
Read the Docs is rebuilding its build farm around uv and isolated builders, one week at a time.
CommaFeed
CommaFeed is patching its way through the attack surface a self-hosted reader inherits
Hive
Hive ships in batches, and this one is all planning accuracy and admin control.
Teable
Teable ships daily, and the work has moved from grid features to platform governance.
Simpplr
Simpplr publishes the research that names the gap, then ships the product that closes it.
See all Calibre-Web alternatives → · See all SiYuan alternatives →
Recent activity from Calibre-Web and SiYuan
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1d agoSiYuanSiYuan 3.8.1 stabilises the agent, skills and Responses API work
- 2d agoSiYuanSlash menu items become configurable; table column widths distribute evenly
- 2d agoSiYuanTable headers left-align by default; double-click closes tabs
- 3d agoSiYuanUser-level agent skills and virtualized grouped-table rendering
- 3d agoSiYuanAI features move to the OpenAI Responses API
- 4d agoSiYuanAgent panel gains a shortcut; blockquote input fixed
- 10d agoCalibre-WebMOBI metadata on upload, reverse-proxy shared-secret login
- 6mo agoCalibre-WebMulti-book editing, Calibre 9 compatibility, API-key leak fixed
- 0y agoCalibre-WebKepub reading, bulk book actions, official Python 3.12 support
- 1y agoCalibre-WebAudio-file metadata extraction and multi-format uploads
- 1y agoCalibre-WebEPUB reader themes and font sizing, multi-address Kindle sending
- 1y agoCalibre-WebSplit library locations, metadata backup, upload mimetype checks
Frequently asked questions
What is the difference between Calibre-Web and SiYuan?
Both compete on the same themes — self-hosted — within Collab. SiYuan is currently shipping more aggressively (velocity 6.3 vs 2.5), with 0 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Calibre-Web better than SiYuan?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. SiYuan is currently shipping more aggressively (velocity 6.3 vs 2.5), with 0 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Collab products to evaluate alongside.
What are the best alternatives to Calibre-Web?
Top Calibre-Web alternatives in Collab are ranked by recent ship velocity. Browse the "Calibre-Web alternatives" section above for the current picks, or visit /alternatives/calibre-web for the full list with editorial commentary on each.
What are the best alternatives to SiYuan?
Top SiYuan alternatives in Collab are ranked by recent ship velocity. Browse the "SiYuan alternatives" section above for the current picks, or visit /alternatives/siyuan for the full list with editorial commentary on each.