diff --git a/pkgs/build-support/dlang/builddubpackage/import-dub-lock.nix b/pkgs/build-support/dlang/builddubpackage/import-dub-lock.nix
index 121d21df9d99..3c7c2279a0e3 100644
--- a/pkgs/build-support/dlang/builddubpackage/import-dub-lock.nix
+++ b/pkgs/build-support/dlang/builddubpackage/import-dub-lock.nix
@@ -41,6 +41,7 @@ let
       src = fetchgit {
         url = repository;
         rev = version;
+        fetchSubmodules = true; # this is the default, but let's be explicit
         inherit sha256;
       };
     };
diff --git a/pkgs/build-support/dlang/dub-to-nix/dub-to-nix.py b/pkgs/build-support/dlang/dub-to-nix/dub-to-nix.py
index 879acc5f4acb..78073aff504c 100755
--- a/pkgs/build-support/dlang/dub-to-nix/dub-to-nix.py
+++ b/pkgs/build-support/dlang/dub-to-nix/dub-to-nix.py
@@ -57,7 +57,7 @@ for pname in depsDict:
         repository = depDict["repository"]
         strippedRepo = repository[4:]
         eprint(f"Fetching {pname}@{version} ({strippedRepo})")
-        command = ["nix-prefetch-git", strippedRepo, version]
+        command = ["nix-prefetch-git", "--fetch-submodules", strippedRepo, version]
         rawRes = subprocess.run(command, check=True, text=True, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL).stdout
         sha256 = json.loads(rawRes)["sha256"]
         lockedDepsDict[pname] = {"version": version, "repository": strippedRepo, "sha256": sha256}