diff --git a/autoload/nim.vim b/autoload/nim.vim
index 5d6c5b7..c401c96 100644
--- a/autoload/nim.vim
+++ b/autoload/nim.vim
@@ -19,6 +19,8 @@ fun! nim#init()
   let cmd = printf("nim --dump.format:json --verbosity:0 dump %s", s:CurrentNimFile())
   let raw_dumpdata = system(cmd)
   if !v:shell_error && expand("%:e") == "nim"
+    let false = 0 " Needed for eval of json
+    let true = 1 " Needed for eval of json
     let dumpdata = eval(substitute(raw_dumpdata, "\n", "", "g"))
     
     let b:nim_project_root = dumpdata['project_path']