diff --git a/meson.build b/meson.build
index 090924fc..bd195229 100644
--- a/meson.build
+++ b/meson.build
@@ -151,7 +151,9 @@ core = custom_target('core.zip',
     'cd ' + meson.project_source_root() +
     ' && echo "Rebuilding core.zip" && rm -f ' + meson.current_build_dir() + '/core.zip && ' +
     'zip -r ' + meson.current_build_dir() + '/core.zip scripts fonts icons shaders'
-  ]
+  ],
+  build_always: true,
+  build_by_default: true
 )
 
 prosperon_raw = executable('prosperon_raw', sources,
@@ -179,7 +181,8 @@ prosperon = custom_target('prosperon',
     '@INPUT1@',
     '@OUTPUT@'
   ],
-  build_always: true
+  build_always: true,
+  build_by_default: true
 )
 
 prosperon_dep = declare_dependency(
@@ -194,7 +197,8 @@ copy_tests = custom_target(
     join_paths(meson.source_root(), 'tests'),
     meson.build_root()
   ],
-  build_always: true
+  build_always: true,
+  build_by_default: true
 )
 
 tests = [
diff --git a/scripts/core/engine.js b/scripts/core/engine.js
index 75452249..c7d911de 100644
--- a/scripts/core/engine.js
+++ b/scripts/core/engine.js
@@ -1237,11 +1237,10 @@ var script_fn = function script_fn(path) {
       throw new Error(`Module ${module_name} must return a value`)
     parsed.module_fn = module_fn
   }
-
-  if (parsed.program) {
-    var prog_script = `(function use_${module_name}() { var self = this; var $ = this.__proto__; ${parsed.program}})`
-    parsed.prog_fn = js.eval(file, prog_script)
-  }
+  
+  parsed.program ??= ""
+  var prog_script = `(function use_${module_name}() { var self = this; var $ = this.__proto__; ${parsed.program}})`
+  parsed.prog_fn = js.eval(file, prog_script)
 
   return parsed
 }.hashify()
diff --git a/source/jsffi.c b/source/jsffi.c
index ae589786..88b3776e 100644
--- a/source/jsffi.c
+++ b/source/jsffi.c
@@ -5881,8 +5881,10 @@ static const JSCFunctionListEntry js_debug_funcs[] = {
 JSC_SCALL(io_rm,
   if (!PHYSFS_delete(str)) ret = JS_ThrowReferenceError(js,"could not remove %s. %s", str, PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
 )
+
 JSC_SCALL(io_mkdir,
-  if (!PHYSFS_mkdir(str)) ret = JS_ThrowReferenceError(js,"could not make directory %s. %s", str, PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));)
+  if (!PHYSFS_mkdir(str)) ret = JS_ThrowReferenceError(js,"could not make directory %s. %s", str, PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
+)
 
 JSC_SCALL(io_exists, ret = JS_NewBool(js,PHYSFS_exists(str)); )
 
diff --git a/tests/empty.js b/tests/empty.js
index 1788a682..e69de29b 100644
--- a/tests/empty.js
+++ b/tests/empty.js
@@ -1 +0,0 @@
-os.exit(1)