Im launching a new phoenix app with fly launch
The dockerfile that is generated has the following:
ARG BUILDER_IMAGE="docker.io/hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="docker.io/debian:${DEBIAN_VERSION}"
But fly launch will have the following error:
✓ Configuration is valid
==> Building image
==> Building image with Depot
--> build: ()
[+] Building 1.1s (3/3) FINISHED
=> [internal] load build definition from Dockerfile 0.1s
=> => transferring dockerfile: 2.82kB 0.1s
=> CANCELED [internal] load metadata for docker.io/library/debian:bookworm-202506 0.9s
=> ERROR [internal] load metadata for docker.io/hexpm/elixir:1.18.4-erlang-27.3.4 0.9s
------
> [internal] load metadata for docker.io/hexpm/elixir:1.18.4-erlang-27.3.4-debian-bookworm-20250610-slim:
------
==> Building image
==> Building image with Depot
--> build: ()
[+] Building 0.5s (3/3) FINISHED
=> [internal] load build definition from Dockerfile 0.1s
=> => transferring dockerfile: 2.82kB 0.1s
=> [internal] load metadata for docker.io/library/debian:bookworm-20250610-slim 0.3s
=> ERROR [internal] load metadata for docker.io/hexpm/elixir:1.18.4-erlang-27.3.4 0.4s
------
> [internal] load metadata for docker.io/hexpm/elixir:1.18.4-erlang-27.3.4-debian-bookworm-20250610-slim:
------
Error: failed to fetch an image or build from source: error building: failed to solve: docker.io/hexpm/elixir:1.18.4-erlang-27.3.4-debian-bookworm-20250610-slim: failed to resolve source metadata for docker.io/hexpm/elixir:1.18.4-erlang-27.3.4-debian-bookworm-20250610-slim: no match for platform in manifest: not found
Looking at a previous, working, dockerfile fly generated for me last year for a different project, the BUILDER_IMAGE
and RUNNER_IMAGE
are the following:
ARG BUILDER_IMAGE="hexpm/elixir:${ELIXIR_VERSION}-erlang-${OTP_VERSION}-debian-${DEBIAN_VERSION}"
ARG RUNNER_IMAGE="debian:${DEBIAN_VERSION}"
The newly generated dockerfile has pre-pended docker.io/
to the variables. Removing them makes the dockerfile work.
Wondering if anyone knows why the generated dockerfile is wrong?