diff --git a/src/model/project/project.lua b/src/model/project/project.lua
index 9d4a0777..13114d85 100644
--- a/src/model/project/project.lua
+++ b/src/model/project/project.lua
@@ -382,7 +382,11 @@ function ProjectService:run(name, env)
     p_path, err = self.is_project(ProjectService.path, name)
   end
   if p_path then
-    local _, code = self.current:readfile(ProjectService.MAIN)
+    local ok, code = self.current:readfile(ProjectService.MAIN)
+    if not ok then return nil, code, p_path end
+    if type(code) ~= 'string' then
+      return nil, FS.messages.unreadable(ProjectService.MAIN), p_path
+    end
     local content, c_err = codeload(code, env)
     return content, c_err, p_path
   end
diff --git a/src/util/lua.lua b/src/util/lua.lua
index 299ff7a4..beca8068 100644
--- a/src/util/lua.lua
+++ b/src/util/lua.lua
@@ -14,6 +14,9 @@ end
 --- @return function? chunk
 --- @return string? err
 local codeload = function(code, env)
+  if type(code) ~= 'string' then
+    return nil, ('code must be a string (got %s)'):format(type(code))
+  end
   local f, err = loadstring(code)
 
   if not f then return nil, err end