Thoreau BASIC: a GW-BASIC interpreter that boots straight off UEFI, no OS needed
Thoreau BASIC is a GW-BASIC-compatible interpreter that boots directly from UEFI firmware, with no operating system underneath. It sizes the data segment to the largest block of conventional memory the firmware reports, which on a modern machine is gigabytes, and paints PSET, LINE and CIRCLE onto the native framebuffer. Disk I/O runs straight on the UEFI Simple File System, so programs SAVE and LOAD like 1985 but without the 64KB ceiling.