DH Lab developer Sheean Spoel added extensions to an existing treebank query application (GrETEL). These extensions address user needs expressed by multiple linguistic researchers and include facilities for uploading one’s own data and metadata. Conversion and cleaning modules for uploading data in CHAT format were added. The extensions also offer new facilities for analysing the results of treebank queries in terms of data, metadata and combinations of those. This new version (4) of GrETEL builds on the work of Martijn van der Klis and is directed by the applicant prof. dr. Jan Odijk.