diff --git a/packages/overlays/matrix-synapse/patches/0004-nix-Update-flake.patch b/packages/overlays/matrix-synapse/patches/0004-nix-Update-flake.patch
new file mode 100644
index 0000000..36f1e19
--- /dev/null
+++ b/packages/overlays/matrix-synapse/patches/0004-nix-Update-flake.patch
@@ -0,0 +1,61 @@
+From 33cb357d30e5817bf679fc161a3a333a37579188 Mon Sep 17 00:00:00 2001
+From: Rory& <root@rory.gay>
+Date: Thu, 13 Nov 2025 13:57:10 +0100
+Subject: [PATCH 04/19] nix: Update flake
+
+Signed-off-by: Rory& <root@rory.gay>
+---
+ flake.lock | 12 ++++++------
+ flake.nix | 2 +-
+ 2 files changed, 7 insertions(+), 7 deletions(-)
+
+diff --git a/flake.lock b/flake.lock
+index 4e2f01153b..0f2de20b2b 100644
+--- a/flake.lock
++++ b/flake.lock
+@@ -165,11 +165,11 @@
+ },
+ "nixpkgs_2": {
+ "locked": {
+- "lastModified": 1748217807,
+- "narHash": "sha256-P3u2PXxMlo49PutQLnk2PhI/imC69hFl1yY4aT5Nax8=",
++ "lastModified": 1762943920,
++ "narHash": "sha256-ITeH8GBpQTw9457ICZBddQEBjlXMmilML067q0e6vqY=",
+ "owner": "NixOS",
+ "repo": "nixpkgs",
+- "rev": "3108eaa516ae22c2360928589731a4f1581526ef",
++ "rev": "91c9a64ce2a84e648d0cf9671274bb9c2fb9ba60",
+ "type": "github"
+ },
+ "original": {
+@@ -236,11 +236,11 @@
+ "nixpkgs": "nixpkgs_3"
+ },
+ "locked": {
+- "lastModified": 1748313401,
+- "narHash": "sha256-x5UuDKP2Ui/TresAngUo9U4Ss9xfOmN8dAXU8OrkZmA=",
++ "lastModified": 1763001554,
++ "narHash": "sha256-wsfhRTuxu6f06RMmP4JWcq3wWRlmYtQaJZ6b3f+EJ94=",
+ "owner": "oxalica",
+ "repo": "rust-overlay",
+- "rev": "9c8ea175cf9af29edbcff121512e44092a8f37e4",
++ "rev": "315d97eb753cee8e1aa039a5e622b84d32a454bb",
+ "type": "github"
+ },
+ "original": {
+diff --git a/flake.nix b/flake.nix
+index cc41490a41..50ae70e989 100644
+--- a/flake.nix
++++ b/flake.nix
+@@ -82,7 +82,7 @@
+ #
+ # NOTE: We currently need to set the Rust version unnecessarily high
+ # in order to work around https://github.com/matrix-org/synapse/issues/15939
+- (rust-bin.stable."1.87.0".default.override {
++ (rust-bin.stable."1.89.0".default.override {
+ # Additionally install the "rust-src" extension to allow diving into the
+ # Rust source code in an IDE (rust-analyzer will also make use of it).
+ extensions = [ "rust-src" ];
+--
+2.53.0
+
|
