Constant NODE_MAJOR_FLOOR 

pub const NODE_MAJOR_FLOOR: u32 = 18; // 18u32

Minimum supported Node.js major version for the node platform binding and for running Bynk’s emitted TypeScript.

Single source of truth for the Node floor: the emitted code targets it, the bynk driver’s doctor command compares a detected node against it, and bynkc’s CLI re-exports it rather than restating the number. Lives in bynk-emit (which emits the TS that runs on Node) so both binaries share one definition (slice 7; was a bynkc const before the driver dropped that dep).