Component Buildpack

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A component buildpack is a buildpack containing /bin/detect and /bin/build executables and that implements the Buildpack Interface.

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Key Points

During the build phase, typical component buildpacks might perform one, or more, of the following actions:

• Read the Buildpack Plan in <plan> to determine what dependencies to provide
• Supply the application with dependencies for launch in <layers>/<layer>
• Reuse application dependencies from a previous image by appending [types] and launch = true to <layers>/<layer>.toml
• Contribute dependencies added in <layers>/<layer> to subsequent buildpacks
• Reuse cached build dependencies from a previous build by appending [types], build = true and cache = true to <layers>/<layer>.toml
• Compile the application source code into object code
• Remove application source code that is not necessary for launch
• Supply start command in <layers>/launch.toml
• Write a partial Software Bill of Materials to <layers>/<layer>.sbom.<ext> describing any dependencies provided in the layer
• Write a partial Software Bill of Materials to <layers>/launch.sbom.<ext> describing any provided application dependencies not associated with a layer
• Write a partial Software Bill of Materials to <layers>/build.sbom.<ext> describing any provided build dependencies not associated with a layer