Hello, it looks like the docker image crystallang/crystal:0.36.0 was updated recently. It seems to contain Crystal version 1.0.0 instead of 0.36.0.
Command to reproduce:
docker run crystallang/crystal:0.36.0 /bin/sh -c “crystal --version”
Crystal 1.0.0 [dd40a2442] (2021-03-22)
LLVM: 10.0.0
Default target: x86_64-unknown-linux-gnu