diff --git a/.github/workflows/build-caddy-l4-image.yml b/.github/workflows/build-caddy-l4-image.yml
index cafa9f8e47..e4cfdf8112 100644
--- a/.github/workflows/build-caddy-l4-image.yml
+++ b/.github/workflows/build-caddy-l4-image.yml
@@ -5,6 +5,12 @@ env:
 name: Build caddy-l4
 on:
   workflow_dispatch:
+  push:
+    branches:
+      - main
+    paths:
+      - docker/DockerfileCaddyL4
+      - .github/workflows/build-caddy-l4-image.yml
 
 permissions: write-all
 
diff --git a/Caddyfile b/Caddyfile
index 96c29626f0..b5e5036414 100644
--- a/Caddyfile
+++ b/Caddyfile
@@ -1,8 +1,10 @@
 {
 	layer4 {
 		:25 {
-			proxy {
-				to windmill_server:2525
+			route {
+				proxy {
+					upstream windmill_server:2525
+				}
 			}
 		}
 	}
diff --git a/docker/DockerfileCaddyL4 b/docker/DockerfileCaddyL4
index eb612cdd46..d2d7bb418f 100644
--- a/docker/DockerfileCaddyL4
+++ b/docker/DockerfileCaddyL4
@@ -1,10 +1,12 @@
-FROM caddy:2.8.4-builder-alpine AS builder
+FROM caddy:2.11.4-builder-alpine AS builder
 
+# caddy-l4 natively registers the `layer4` global option used by the Caddyfile.
+# Do NOT also add RussellLuo/caddy-ext/layer4: it registers the same global
+# option, and building both panics with "global option 'layer4' already registered".
 RUN xcaddy build \
-  --with github.com/mholt/caddy-l4@145ec36251a44286f05a10d231d8bfb3a8192e09 \
-  --with github.com/RussellLuo/caddy-ext/layer4@ab1e18cfe426012af351a68463937ae2e934a2a1
+  --with github.com/mholt/caddy-l4@bd96009ea7373869bb07d61055554f966b1f5088
 
 
-FROM caddy:2.8.4-alpine
+FROM caddy:2.11.4-alpine
 
-COPY --from=builder /usr/bin/caddy /usr/bin/caddy
\ No newline at end of file
+COPY --from=builder /usr/bin/caddy /usr/bin/caddy
diff --git a/flake.nix b/flake.nix
index 3872ee636f..9062fdb4fd 100644
--- a/flake.nix
+++ b/flake.nix
@@ -354,8 +354,7 @@
           (pkgs.writeScriptBin "wm-caddy" ''
             cd ./frontend
             xcaddy build "$@" \
-              --with github.com/mholt/caddy-l4@145ec36251a44286f05a10d231d8bfb3a8192e09 \
-              --with github.com/RussellLuo/caddy-ext/layer4@ab1e18cfe426012af351a68463937ae2e934a2a1
+              --with github.com/mholt/caddy-l4@bd96009ea7373869bb07d61055554f966b1f5088
           '')
           (pkgs.writeScriptBin "wm-setup" ''
             sqlx database create