The old 32-bit K2 (K language) had a superfast ACID DB, GUI, GC, no dependencies (but also no compilter) and was 250K, so 4 independent platforms would still fit in under 1MB; Arthur is now working on KPARC, which has no compiler but does boot on metal and includes GUI, editor, db, filesystem, network, and a lot more, e.g. this http://kparc.com/edit.k is the implementation of native nano-style GUI editor. ; Last I heard, it was still <500KB.
The old 32-bit K2 (K language) had a superfast ACID DB, GUI, GC, no dependencies (but also no compilter) and was 250K, so 4 independent platforms would still fit in under 1MB; Arthur is now working on KPARC, which has no compiler but does boot on metal and includes GUI, editor, db, filesystem, network, and a lot more, e.g. this http://kparc.com/edit.k is the implementation of native nano-style GUI editor. ; Last I heard, it was still <500KB.