diff --git a/pkgs/by-name/si/signal-desktop-bin/signal-desktop-aarch64.nix b/pkgs/by-name/si/signal-desktop-bin/signal-desktop-aarch64.nix
index d2e989160658..40c707422afe 100644
--- a/pkgs/by-name/si/signal-desktop-bin/signal-desktop-aarch64.nix
+++ b/pkgs/by-name/si/signal-desktop-bin/signal-desktop-aarch64.nix
@@ -1,7 +1,7 @@
 { callPackage }:
 callPackage ./generic.nix { } {
   pname = "signal-desktop-bin";
-  version = "7.52.0";
+  version = "7.55.0";
 
   libdir = "usr/lib64/signal-desktop";
   bindir = "usr/bin";
@@ -10,6 +10,6 @@ callPackage ./generic.nix { } {
     bsdtar -xf $downloadedFile -C "$out"
   '';
 
-  url = "https://download.copr.fedorainfracloud.org/results/useidel/signal-desktop/fedora-42-aarch64/08956500-signal-desktop/signal-desktop-7.52.0-1.fc42.aarch64.rpm";
-  hash = "sha256-kQbCkswCNRnz/K6KpZKJ55bCaM2YFL9wW+erVA+3Nok=";
+  url = "https://download.copr.fedorainfracloud.org/results/useidel/signal-desktop/fedora-42-aarch64/09073923-signal-desktop/signal-desktop-7.55.0-1.fc42.aarch64.rpm";
+  hash = "sha256-rRt2hYyj6kyN0RCupy+hpRJuzq0aaUzP2tsVr2Qd5V4=";
 }
diff --git a/pkgs/by-name/si/signal-desktop-bin/signal-desktop-darwin.nix b/pkgs/by-name/si/signal-desktop-bin/signal-desktop-darwin.nix
index 9b7cc31921be..29140ecf699d 100644
--- a/pkgs/by-name/si/signal-desktop-bin/signal-desktop-darwin.nix
+++ b/pkgs/by-name/si/signal-desktop-bin/signal-desktop-darwin.nix
@@ -6,11 +6,11 @@
 }:
 stdenv.mkDerivation (finalAttrs: {
   pname = "signal-desktop-bin";
-  version = "7.52.0";
+  version = "7.55.0";
 
   src = fetchurl {
     url = "https://updates.signal.org/desktop/signal-desktop-mac-universal-${finalAttrs.version}.dmg";
-    hash = "sha256-GamsV4tWLEWbegUIrmZ4ZpAuRbfZzlxjnEy7FOo4q/E=";
+    hash = "sha256-9PD4SDTACjKSBqIdv3CFtKhRKA5ugbQe2AcWA4hFoqs=";
   };
   sourceRoot = ".";
 
diff --git a/pkgs/by-name/si/signal-desktop-bin/signal-desktop.nix b/pkgs/by-name/si/signal-desktop-bin/signal-desktop.nix
index af5d27764c0d..31e3b0c7dc08 100644
--- a/pkgs/by-name/si/signal-desktop-bin/signal-desktop.nix
+++ b/pkgs/by-name/si/signal-desktop-bin/signal-desktop.nix
@@ -1,12 +1,12 @@
 { callPackage }:
 callPackage ./generic.nix { } rec {
   pname = "signal-desktop-bin";
-  version = "7.52.0";
+  version = "7.55.0";
 
   libdir = "opt/Signal";
   bindir = libdir;
   extractPkg = "dpkg-deb -x $downloadedFile $out";
 
   url = "https://updates.signal.org/desktop/apt/pool/s/signal-desktop/signal-desktop_${version}_amd64.deb";
-  hash = "sha256-SOe0BAEE5ljBb/OM3F7ejQQk8/KROFf7kfs/Gtp+bSY=";
+  hash = "sha256-uc623M/GiIfED1mTFnXUggnFdvDBmngrsdTIlq6QxqM=";
 }
diff --git a/pkgs/by-name/si/signal-desktop-bin/update.sh b/pkgs/by-name/si/signal-desktop-bin/update.sh
index cca3e29ae12c..10b73d331c91 100755
--- a/pkgs/by-name/si/signal-desktop-bin/update.sh
+++ b/pkgs/by-name/si/signal-desktop-bin/update.sh
@@ -15,6 +15,9 @@ latestBuildInfoAarch64=$(curl \
   | jq '.builds.latest_succeeded')
 latestBuildAarch64=$(jq '.id' <<< $latestBuildInfoAarch64)
 latestVersionAarch64=$(jq -r '.source_package.version' <<< $latestBuildInfoAarch64)
+latestPrettyVersionAarch64="${latestVersionAarch64%-*}"
+
+darwinHash="$(nix hash convert --hash-algo sha256 --to sri "$(nix-prefetch-url "https://updates.signal.org/desktop/signal-desktop-mac-universal-${latestVersion}.dmg")")"
 
 echo "Updating signal-desktop for x86_64-linux"
 update-source-version signal-desktop-bin "$latestVersion" \
@@ -22,12 +25,11 @@ update-source-version signal-desktop-bin "$latestVersion" \
   --file="$SCRIPT_DIR/signal-desktop.nix"
 
 echo "Updating signal-desktop for aarch64-linux"
-update-source-version signal-desktop-bin "$latestVersionAarch64" "" \
+update-source-version signal-desktop-bin "$latestPrettyVersionAarch64" "" \
   "https://download.copr.fedorainfracloud.org/results/useidel/signal-desktop/fedora-42-aarch64/$(printf "%08d" $latestBuildAarch64)-signal-desktop/signal-desktop-$latestVersionAarch64.fc42.aarch64.rpm" \
   --system=aarch64-linux \
   --file="$SCRIPT_DIR/signal-desktop-aarch64.nix"
 
 echo "Updating signal-desktop for darwin"
-update-source-version signal-desktop-bin "$latestVersion" \
-  --system=aarch64-darwin \
-  --file="$SCRIPT_DIR/signal-desktop-darwin.nix"
+sed -i "s|version = \".*\";|version = \"${latestVersion}\";|" "$SCRIPT_DIR/signal-desktop-darwin.nix"
+sed -i "s|hash = \"sha256-[^\"]*\";|hash = \"${darwinHash}\";|" "$SCRIPT_DIR/signal-desktop-darwin.nix"