One of the challenges related to enrichment analysis tools such as Enrichr is provenance: the ability to repeat enrichment results, even after libraries and computational methods for computing enrichment have been updated. To address this issue, we created a ‘Legacy’ category in which we place older libraries so that these can be accessed by users who wish to repeat their own results, or repeat a published result conducted by others. The Legacy category has gene set libraries with a year label. We plan to update libraries once a year to balance consistency of results with timely content. Initially, the gene set libraries of Enrichr were not made available for download. Since 2015, we have made all libraries accessible for direct download. This enables other computational biologists to explore the deep relationships between genes in annotated gene sets, and to develop new tools using these libraries.
