diff --git a/stacks/fish-s2/compose.yaml b/stacks/fish-s2/compose.yaml
index 7098701..450104f 100644
--- a/stacks/fish-s2/compose.yaml
+++ b/stacks/fish-s2/compose.yaml
@@ -26,9 +26,16 @@ services:
     image: local/fish-s2:${FISH_S2_TAG}
     build:
       context: https://github.com/fishaudio/fish-speech.git#${FISH_S2_SHA}
-      dockerfile: dockerfile
+      # Upstream ships `dockerfile.dev` (lowercase, dev/test image)
+      # rather than a plain Dockerfile — there is no production
+      # Dockerfile. Their intended path is `docker compose --profile
+      # server up` against their own compose.yml; we use the same
+      # underlying dockerfile.dev image but layer our own compose on
+      # top so it slots into our fleet conventions (restart, labels,
+      # bind mounts, healthcheck).
+      dockerfile: dockerfile.dev
       args:
-        # Upstream's Dockerfile reads BACKEND to choose CUDA vs CPU
+        # Upstream's dockerfile.dev reads BACKEND to choose CUDA vs CPU
         # paths during pip install. We always want CUDA on irv-ml1.
         BACKEND: cuda
     container_name: fish-s2