Deploying docker compose appears to be broken

[elliots]

I have tried both with my project, and with your example project from the forum thread (https://github.com/fly-apps/rate-limiter-demo.git).

If there is a Dockerfile it will build using that even if i have [build.compose]
If I rename the dockerfile, it complains there are no buildpacks or Dockerfile

• Operating system
  macos 26.5.1

• fly version
  fly v0.4.64 darwin/arm64 Commit: 7131b81 BuildDate: 2026-06-30T22:50:58Z

** Paste your fly.toml

app = 'testabc123'
primary_region = 'syd'

[build.compose]
  file = "compose.yml"

[http_service]
  internal_port = 3000
  force_https = true
  auto_stop_machines = 'stop'
  auto_start_machines = true
  min_machines_running = 0
  processes = ['app']

[[vm]]
  memory = '1gb'
  cpu_kind = 'shared'
  cpus = 1
  memory_mb = 1024

** Command output: **

✓ Configuration is valid
--> Verified app config
==> Building image
==> Building image
Error: failed to fetch an image or build from source: app does not have a Dockerfile or buildpacks configured. See https://fly.io/docs/reference/configuration/#the-build-section