Join us for our weekly series of short talks: nf-core/bytesize.

Just 15 minutes + questions, we focus on topics about using and developing nf-core pipelines. These are recorded and made available at , helping to build an archive of training material. Got an idea for a talk? Let us know on the #bytesize Slack channel!

With the advent of DSL2, nf-core pipelines began to use separate containers for every process. Now, many nf-core pipelines can have upwards of 50 different software containers in a single run. Traditionally, finding the URIs for each of these containers was a difficult task, with several people developing tooling based around regular expressions.

In Nextflow 23.09.0-edge a new subcommand was added called nextflow inspect. This command retrieves all of the containers that will be used by a pipeline run and returns them in Nextflow config syntax.

In this talk, Phil Ewels (@ewels) will guides us through the process of fetching container URIs using nextflow inspect and show how this can be used to customise containers in a pipeline. This may be of particular use to people working in environments that cannot access our public container registries or who may need additional steps in their container verification steps.