Bundle Definition

An LV2 Bundle is a directory containing the file manifest.ttl at the top level, which is written in Turtle. See the Simple Amplifier manifest for an example.

Note that host developers should use a library, such as Lilv which automatically discovers and loads bundles correctly. This page describes the format of an LV2 bundle, but host authors typically do not need to be concerned with the details.

• All information necessary for a host to discover (but not necessarily use) the contents of a bundle MUST be present in manifest.ttl.
• The host can discover which plugins are present by scanning manifest.ttl for statements like <plugin-uri> a lv2:Plugin.
• The data files for each plugin are listed with the rdfs:seeAlso property, for example <plugin-uri> rdfs:seeAlso <datafile.ttl>.
• Descriptions may be split across several files, and several bundles. File boundaries are not significant.
• If a statement like <extension-uri> a lv2:Specification is found, then <extension-uri> is specification which may contain information like additional plugin categories, properties, and human-readable labels for things. The host SHOULD load the corresponding data files.
• If a statement like <preset-uri> a pset:Preset is found, then <preset-uri> is a preset. The lv2:appliesTo property indices which plugin the preset applies to. See the presets extension for details.

Installation

• The name of a bundle itself MUST NOT be given any long-term significance (for example, in saved files).
  • Hosts may include special plugin bundles as part of their installation and depend on the existence of those bundles in their search path, but otherwise the discovery process should be identical.
  • Users MUST be able to rename installed bundle directories without any save files breaking.

Discovery

• If a host encounters a bundle it does not "understand" or care about, it may simply ignore it.
• Hosts MUST consider all data files associated with a plugin/spec/preset/etc (including manifest.ttl) whenever looking for information about a plugin.

Examples

Note that manifest.ttl may contain information about any number of things. A single bundle may contain several plugins, specifications, and presets.

However, it is discouraged to group too many things into a single bundle, since this makes it difficult for the user to manage what they have installed. Instead, put individual plugins, presets, etc., in their own bundle. It is a good idea to give related bundles common name prefix (not suffix) to make their organization clear.

Plugin

• manifest.ttl contains the triple <pluginuri> a lv2:Plugin.
• manifest.ttl MAY contain triples of the form <pluginuri> rdfs:seeAlso <datafile.ttl> which indicates that more information can be found in datafile.ttl.

Specification

• manifest.ttl contains the triple <specuri> a lv2:Specification.
• manifest.ttl MAY contain triples of the form <specuri> rdfs:seeAlso <datafile.ttl> which indicates that more information can be found in datafile.ttl.
• Hosts SHOULD consider this information part of their LV2 specification. Hosts SHOULD NOT hard-code static assumptions about the specification, such as plugin categories or port types (though of course, they may not support unknown types).

UI

• manifest.ttl contains the triple <ui> a foo:MegaWidget where foo:MegaWidget is a "widget" type the host understands (likely one defined in the UI specification).
• manifest.ttl MAY contain triples of the form <ui> rdfs:seeAlso <datafile.ttl> which indicates that more information can be found in datafile.ttl.
• manifest.ttl contains a triple of the form <ui> ui:binary <ui.so> where ui.so is the module to be dynamically loaded by the host.