A Kubernetes-optimized Synapse image, some old example manifests can be found in the kubernetes folder.
For a managed deployment, look at the charts available at;
https://gitlab.com/ananace/charts - supports workers, handles the signing key as a secret, built upon the K8s ingress resource.
https://github.com/dacruz21/matrix-chart/ - lacks workers, mounts a PVC for signing key, includes bridges and a mail relay, requires LoadBalancer support.
To run with workers, create worker configuration files and launch with - for instance;
$ docker run --rm -it \
-v config:/synapse/config:ro \
-v tls:/synapse/tls:ro \
-v keys:/synapse/keys:ro \
ananace/matrix-synapse:latest \
synapse.app.synchrotron \
-c /synapse/config/synchrotron.worker
More information about workers can be found at; https://github.com/matrix-org/synapse/blob/master/docs/workers.md