diff --git a/pkgs/by-name/we/wezterm/package.nix b/pkgs/by-name/we/wezterm/package.nix
index a8b8f756a1a4..e6e8d2697873 100644
--- a/pkgs/by-name/we/wezterm/package.nix
+++ b/pkgs/by-name/we/wezterm/package.nix
@@ -16,7 +16,6 @@
   python3,
   runCommand,
   rustPlatform,
-  unstableGitUpdater,
   vulkan-loader,
   wayland,
   wezterm,
@@ -152,10 +151,7 @@ rustPlatform.buildRustPackage rec {
       #terminal-emulators = nixosTests.terminal-emulators.wezterm;
     };
 
-    # upstream tags are composed with timestamp+commit, e.g.:
-    # 20240203-110809-5046fc22
-    # doesn't make much sense if we are following unstable
-    updateScript = unstableGitUpdater { hardcodeZeroVersion = true; };
+    updateScript = ./update.sh;
   };
 
   meta = with lib; {
diff --git a/pkgs/by-name/we/wezterm/update.sh b/pkgs/by-name/we/wezterm/update.sh
new file mode 100755
index 000000000000..d04296c9bab3
--- /dev/null
+++ b/pkgs/by-name/we/wezterm/update.sh
@@ -0,0 +1,30 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p curl jq git nix-prefetch-git common-updater-scripts gnused nix-update
+
+set -euo pipefail
+
+OWNER="wez"
+REPO="wezterm"
+
+NIXPKGS_ROOT=$(git rev-parse --show-toplevel)
+PACKAGE_NIX_ATTR_PATH="wezterm"
+
+# For wezterm, the version is 0-unstable-YYYY-MM-DD, so we need to get the commit date
+# from the latest commit, not the release tag.
+# We also need the latest commit SHA for the rev.
+
+LATEST_COMMIT_INFO=$(curl ${GITHUB_TOKEN:+--user ":$GITHUB_TOKEN"} --location --silent "https://api.github.com/repos/$OWNER/$REPO/commits/HEAD")
+LATEST_REV=$(echo "$LATEST_COMMIT_INFO" | jq --raw-output '.sha')
+COMMIT_DATE=$(echo "$LATEST_COMMIT_INFO" | jq --raw-output '.commit.author.date' | cut -d 'T' -f 1)
+
+NEW_VERSION="0-unstable-$COMMIT_DATE"
+
+FETCH_JSON=$(nix-prefetch-git --url "https://github.com/$OWNER/$REPO" --rev "$LATEST_REV" --fetch-submodules)
+FETCH_HASH=$(echo "$FETCH_JSON" | jq --raw-output .hash)
+
+(cd "$NIXPKGS_ROOT" && nix-update wezterm)
+(cd "$NIXPKGS_ROOT" && update-source-version "$PACKAGE_NIX_ATTR_PATH" "$NEW_VERSION" "$FETCH_HASH" --rev="$LATEST_REV")
+
+sed -i -e "s#version = \".*\"#version = \"$NEW_VERSION\"#" "$NIXPKGS_ROOT/pkgs/by-name/we/wezterm/package.nix"
+
+echo "Wezterm update script finished."