diff --git a/nico/backends/sdl2.nim b/nico/backends/sdl2.nim
index 62c4985..3eaa328 100644
--- a/nico/backends/sdl2.nim
+++ b/nico/backends/sdl2.nim
@@ -1829,9 +1829,10 @@ proc getRecordSeconds*(): int =
     return 0
 
 when defined(emscripten):
+  type cbool* {.importc: "bool", nodecl.} = uint8
   type em_callback_func* = proc() {.cdecl.}
   {.push importc.}
-  proc emscripten_set_main_loop*(f: em_callback_func, fps, simulate_infinite_loop: cint)
+  proc emscripten_set_main_loop*(f: em_callback_func, fps: cint, simulate_infinite_loop: cbool)
   proc emscripten_cancel_main_loop*()
   {.pop.}