Typical comp shape
ML infrastructure engineers usually earn ppus, rsu, or pre-ipo options. Common employers include OpenAI, Anthropic, Meta, Nvidia. ML infra hires at frontier labs hold PPUs whose valuation jumps at each funding round trigger tax questions without liquidity.
What Arkansas changes
In Arkansas, every RSU vest, NSO exercise, and ESPP purchase carries 3.9% state tax on top of federal. For a senior ml infrastructure engineer with $300k+ of equity income, the state layer routinely adds $25-45k to the annual bill.
Planning cadence
For a ml infrastructure engineer in Arkansas, the three planning windows are: after each RSU vest (withholding check and sell-vs-hold), before any ISO exercise (AMT model at federal only), and in Q4 (estimated tax top-up to clear the safe harbor).