docker run -it elixir:1.11.2-alpine /bin/bash
For example, if you do the above, you will get angry without bash.
docker: Error response from daemon: OCI runtime create failed: container_linux.go:370: starting container process caused: exec: "/bin/bash": stat /bin/bash: no such file or directory: unknown.
docker run -it elixir:1.11.2-alpine /bin/ash
ash is used for the shell of alpine.