diff --git a/lua/lazy/core/loader.lua b/lua/lazy/core/loader.lua
index 9e899fa..af36abc 100644
--- a/lua/lazy/core/loader.lua
+++ b/lua/lazy/core/loader.lua
@@ -121,11 +121,11 @@ function M.packadd(plugin)
   -- vim.cmd.packadd(plugin.name)
   -- M.source_runtime(plugin, "/after/plugin")
   if M.init_done then
-    M.source_runtime(plugin.dir, "/plugin")
+    M.source_runtime(plugin.dir, "plugin")
     if vim.g.did_load_filetypes == 1 then
-      M.source_runtime(plugin.dir, "/ftdetect")
+      M.source_runtime(plugin.dir, "ftdetect")
     end
-    M.source_runtime(plugin.dir, "/after/plugin")
+    M.source_runtime(plugin.dir, "after/plugin")
   end
 end
 
diff --git a/lua/lazy/manage/task/plugin.lua b/lua/lazy/manage/task/plugin.lua
index 7fcf815..c1703c4 100644
--- a/lua/lazy/manage/task/plugin.lua
+++ b/lua/lazy/manage/task/plugin.lua
@@ -10,9 +10,10 @@ M.build = {
   end,
   run = function(self)
     Loader.load(self.plugin, { task = "build" })
-    -- when installing during startup, add the package
-    -- to make sure all runtime files are loaded
-    Loader.packadd(self.plugin, true)
+
+    -- we need to source its plugin files before startup,
+    -- to make sure the build command has everything available
+    Loader.source_runtime(self.plugin.dir, "plugin")
 
     local build = self.plugin.build
     if build then