This image intends to provide a glic compatible execution environment for binaries that expect glibc style dynamic linking.
# ldd your-binary
/lib64/ld-linux-x86-64.so.2 (0x7fe725e2b000)
libpthread.so.0 => /lib64/ld-linux-x86-64.so.2 (0x7fe725e2b000)
libm.so.6 => /lib64/ld-linux-x86-64.so.2 (0x7fe725e2b000)
libc.so.6 => /lib64/ld-linux-x86-64.so.2 (0x7fe725e2b000)
The compatibility is provided by libc6-compat alpine package https://pkgs.alpinelinux.org/package/edge/main/x86/libc6-compat.