Dijkstra's timeless advice. Also recommend: "On the Design of Programming Languages" N. Wirth CS-TR-73-403 "Hints on programming language design" C.A.R. Hoar

Dijkstra's timeless advice. Also recommend: "On the Design of Programming Languages" N. Wirth CS-TR-73-403 "Hints on programming language design" C.A.R. Hoare "The Essence of Programming Languages" Niklaus Wirth