diff --git a/src/emacs/lean-mode.el b/src/emacs/lean-mode.el
index 62b82ef4a6..1ffa260b84 100644
--- a/src/emacs/lean-mode.el
+++ b/src/emacs/lean-mode.el
@@ -153,6 +153,7 @@ will be flushed everytime it's executed."
               `("--cache" ,cache-file-name)
             '()))
          (lean-mode-option "--lean")
+         (default-directory (or (lean-project-find-root) default-directory))
          (process-args (append `(,process-name
                                  ,process-buffer-name
                                  ,(lean-get-executable lean-executable-name)
diff --git a/src/emacs/lean-project.el b/src/emacs/lean-project.el
index 5550fe9095..63f6687aba 100644
--- a/src/emacs/lean-project.el
+++ b/src/emacs/lean-project.el
@@ -11,7 +11,10 @@
   "Project file name")
 
 (defun lean-project-find-root ()
-  (lean-find-file-upward lean-project-file-name))
+  (let ((p (f--traverse-upwards (f-exists? (f-expand lean-project-file-name it))
+                                (f-dirname (buffer-file-name)))))
+    (if p (file-name-as-directory p)
+          nil)))
 
 (defun lean-project-inside-p ()
   (if (lean-project-find-root) t nil))