How Do Tachiyomi Extensions Update And Manage Source Lists?

In technical shorthand, Tachiyomi treats each extension as a self-contained module that registers one or more sources. The app periodically fetches a remote JSON manifest that enumerates extension packages, version codes, and download URLs; updates happen when the manifest reports a newer version than what’s installed. Installing an update downloads the new APK and the system installs it over the old package, updating whatever source classes are bundled inside.

Each source inside an extension exposes metadata (ID, language, name) which Tachiyomi uses to populate the source list and to map library entries back to their origin. Because the mapping relies on package name plus source ID, removing or renaming sources in an update can orphan entries or require manual migration. Users can manage visibility via the Sources manager—disabling, sorting or filtering so searches only hit the set they want.

I appreciate the modularity: it makes adding obscure languages and niche sites straightforward, even if occasionally a source disappears and I need to fiddle with migrations. It’s a neat balance of flexibility and occasional maintenance, which keeps me engaged.

I've tinkered with Tachiyomi extensions a lot, so here's the gist in plain terms: the app treats each extension as an installable APK that knows how to talk to one or more manga sources. There's a manifest (a JSON index the app fetches from an official or forked server) that lists available extension packages, their package names, version codes, languages, and download URLs. When Tachiyomi checks for updates it compares the installed extension version against that manifest; if a newer version exists the app will show an update and let you download the new APK and install it.

Inside each extension are the actual source implementations. Each source has an internal ID, a name, and language metadata; the app reads those from the installed extension and builds the 'Sources' list you scroll through. Updating an extension can add, change, or remove sources because the code inside the APK changed — that’s why sometimes your library throws errors after an update if a source was renamed or dropped. The app uses the package name + source ID to map your manga entries to their originating source, so extension updates that preserve those identifiers generally keep your library intact.

For Everyday Use: you can enable or disable sources from the Sources manager, update extensions manually or let the app auto-update, and install local APKs if you prefer builds from other forks. If a source dies, migration tools or searching other extensions can move your series. I like that system — it’s modular and powerful, just a little finicky when sources get shuffled, but that’s part of the hobby for me.

I get excited about the user side of it: Tachiyomi shows updates in the Extensions tab and gives simple install buttons, which makes keeping sources fresh painless. Under the hood, though, the app is just comparing versions from a remote manifest and fetching APKs; the manifest is what tells the app which extension packages exist and where to download them. When an update is available you’ll usually see a version bump and change log from the extension maintainer, then tap to download and install.

From the perspective of managing source visibility, the Sources screen is your playground. It lists every source exposed by installed extensions, grouped by language and sometimes by extension. You can disable sources you never use to declutter searches, and searches only query enabled sources. Some extensions have settings of their own (like preferred image quality or page selectors), so updating might add new toggles under that extension’s settings.

A quick tip I follow: if a chapter or series breaks after an update, try disabling/re-enabling the source, clearing the extension cache, or reinstalling the previous build if you kept it. It keeps the reading experience smooth for me, and I enjoy seeing new features pop up after a fresh update.