US Immigration Data: open historical datasets on US immigration procedure and enforcement

Machine-readable historical time series and reference datasets on US immigration procedure and enforcement. The underlying government sources publish the current value of most of this information and overwrite it without notice or archive; these datasets re-check those sources on a schedule and bank each observed change, so the history - what changed, when, and whom it affected - stays available in a form the official pages do not provide. Nine datasets: TPS designation, extension and termination history traced to Federal Register documents (1994-2026); USCIS filing-fee history across 40 forms with each change traced to its rule; month-over-month Visa Bulletin movement across all four tables; active 287(g) agreements with per-agency model and signing date; banked ICE detention statistics releases with computed change between releases; DOJ-recognized free legal-aid provision per immigration court; per-country TPS work-permit (EAD) status and current Form I-9 dates; and a verified dated change log. Every value cites its official government source inside the file. The underlying facts originate with the cited US agencies and carry no copyright; this project's contribution is the curation, normalization, verification and banked history. JSON is canonical and carries per-file metadata with source URLs and as-of dates; CSV flattenings are provided for convenience. Collection is automated and refreshed daily. Canonical page: https://migrantusa.com/datasets/ - Methodology: https://migrantusa.com/methodology/