The NHGIS Metadata and Data Extract APIs are now at version 1.0 and are generally available to all NHGIS users! With the new version, any IPUMS user registered with NHGIS can explore NHGIS metadata and create NHGIS data extracts programmatically via the API. See the API developer documentation for all the details!
Our invite-only API Beta Program continues for those users who would like to remain on the leading edge.