Typical comp shape
API engineers usually earn double-trigger rsu or isos. Common employers include Stripe, Twilio, Plaid. API-platform hires at Stripe-style pre-IPOs hold double-trigger RSUs whose tax event only lands at liquidity.
What Tennessee changes
Tennessee has no wage income tax, which is structurally favorable for api engineers with meaningful RSU comp. The savings vs a CA-resident colleague can be $30-60k per year at senior IC levels. That math is why Austin and Seattle are the two top relocation destinations for Bay Area tech workers.
Planning cadence
For a api engineer in Tennessee, 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). A move-out question — if you're considering leaving Tennessee for a high-tax state, time it around vesting.