All projects related to GBOL (ontology and API's) are located in the GBOL Group at GitLab
The ontology is written in a combination of OWL and ShEx and is located here in the root-ontology.ttl file.
Additional ontology files in the ShEx and OWL format are present in the generated folder in the GBOLOntology project.
We have generated an R and JAVA api and are located in the corresponding repositories (RGBOLapi, GBOLapi, GBOLjar. The JAVA api is written using the Gradle build system and can either be used directly as a project or as a dependency.