Updated project metadata. Pristionchus pacificus has emerged as a valuable model system for comparative and evolutionary-developmental biology (evo-devo) studies alongside the classic model nematode C. elegans. Previous studies have identified a lack of conservation of genetic networks underlying conserved traits, referred to as developmental systems drift. However, the conservation – or lack thereof – of epigenetic pathways which regulate development have not been investigated. In the manuscript associated with this study, we present an “epigenetic toolkit” for P. pacificus and C. elegans to compare and contrast epigenetic pathways. Assembly of this toolkit was done by identifying orthologous genes, including the “writers” and “erasers” of histone modifications. To complement this evolutionary approach, here we produce a data set of the suite of histone modifications present in P. pacificus.