Docs / BuckleScript / ComparisonToJsoo

Comparison to Js_of_ocaml

Js_of_ocaml is a popular compiler which compiles OCaml’s bytecode into JavaScript. It is the inspiration for this project, and has already been under development for several years and is ready for production. BuckleScript’s motivation, like js_of_ocaml, is to unify the ubiquity of the JavaScript platform and the truly sophisticated type system of OCaml.

However, there are a few areas that BuckleScript approaches differently:

  • Js_of_ocaml takes low-level bytecode from OCaml compiler, BuckleScript takes the high-level rawlambda representation from OCaml compiler.

  • Js_of_ocaml focuses more on existing OCaml ecosystem (OPAM) while BuckleScript’s major goal is to target NPM/Yarn and existing JS workflows.

  • Js_of_ocaml and BuckleScript have slightly different runtime encoding in several places. For example, BuckleScript encodes OCaml Array as JS Array while js_of_ocaml requires its index 0 to be of value 0.

See also the Introduction page for more info on BuckleScript's emphasis.