Stack & Flex is a free NFL DFS workbench

Stack & Flex is a free hub for NFL daily fantasy. The first tool is a lineup optimizer that runs in your browser. You bring a salary file from DraftKings or FanDuel and your own projections. Nothing about the player pool is scraped.

Classic and single-game rules live in one config: salary caps, roster slots, the DraftKings two-game minimum, the FanDuel four-player team limit, and the captain multipliers. When a site changes a rule, the fix is that config, not a buried formula.

The site does not take entries, move money, or sell picks. Salary files stay on your device. A newsletter is planned; the signup form does not store addresses yet.