One frozen snapshot of federal budget data through three modern stacks: a diffable Power BI model in TMDL, a dbt + DuckDB warehouse with 82 tests — and the five things the tests caught in real data.
A natural-language-to-SQL copilot with no LLM in it: a deterministic router, 40 pre-approved SELECTs, results frozen at build time, and a refusal taxonomy — out-of-scope, untracked-agency, injection, and more, each with a named reason.
A budget workbench in Excel: four template workbooks, six VBA macros for reconciliation, variance, and the close checklist — plus Python twins of the two computational macros so every number reproduces headlessly.