ecs-init is a RPM package shipped with Amazon Linux by default, and I think could be easily ported to other RPM-powered Linux distributions, such as RedHat Linux, CentOS, Fedora, and etc. To run Amazon ECS container agent on non-RPM-powered systems, you can instead run a docker container of amazon/amazon-ecs-agent. Refer to the section To install the Amazon ECS container agent on a non-Amazon Linux EC2 instance from the lower part of Installing the Amazon ECS Container Agent for more details
Below is an example, copy-and-paste from Installing the Amazon ECS Container Agent, of how to run a amazon-ecs-agent instance
ubuntu:~$ sudo docker run --name ecs-agent \
--detach=true \
--restart=on-failure:10 \
--volume=/var/run/docker.sock:/var/run/docker.sock \
--volume=/var/log/ecs/:/log \
--volume=/var/lib/ecs/data:/data \
--volume=/sys/fs/cgroup:/sys/fs/cgroup:ro \
--volume=/var/run/docker/execdriver/native:/var/lib/docker/execdriver/native:ro \
--publish=127.0.0.1:51678:51678 \
--env=ECS_LOGFILE=/log/ecs-agent.log \
--env=ECS_LOGLEVEL=info \
--env=ECS_DATADIR=/data \
--env=ECS_CLUSTER=cluster_name \
amazon/amazon-ecs-agent:latest