diff --git a/pkgs/development/tools/parsing/tree-sitter/grammars/grammar-sources.nix b/pkgs/development/tools/parsing/tree-sitter/grammars/grammar-sources.nix
index 8d1e6f580439..d1aa6763f38f 100644
--- a/pkgs/development/tools/parsing/tree-sitter/grammars/grammar-sources.nix
+++ b/pkgs/development/tools/parsing/tree-sitter/grammars/grammar-sources.nix
@@ -1679,10 +1679,10 @@
   };
 
   nim = {
-    version = "0.6.2-unstable-2026-01-11";
+    version = "0.6.2-unstable-2026-03-21";
     url = "github:alaviss/tree-sitter-nim";
-    rev = "9b4ede21a6ca866d29263f6b66c070961bc622b4";
-    hash = "sha256-3BHcQrLNcXe1RMkV7ECCMzzEukgTlARH3+DDo2M5b0w=";
+    rev = "3878440d9398515ae053c6f6024986e69868bb74";
+    hash = "sha256-mdAT1jTFeVP8TYi4H36sjd826KmxHQ1EZ+8gd37NGfY=";
     meta = {
       license = lib.licenses.mpl20;
       maintainers = with lib.maintainers; [