Getting "not found" errors on snuba-consumer and snuba-replacer

I’m working on getting onpremise up and running in AWS ECS. I’ve worked around some of the networking issues and written ECS task and service definitions. However, I can’t get the snuba consumer and replacer containers to run. They exit with

./docker_entrypoint.sh: line 16: exec: consumer --dataset events --auto-offset-reset=latest --max-batch-time-ms 750: not found