With k6, can we use Prometheus instead of Influxdb?
Hi, unfortunately currently no 
There is an PR that is now quite old https://github.com/loadimpact/k6/pull/478. I intend on picking it up at some point but unfortunately, it probably won’t be very soon
At the moment it’s Influxdb, Kafka, Load Impact Insights and json … if you can make the json into something and the generation of json is not too slow for your use case you can put that into anything. Next week (hopefully) we will release a version with statsd and datadog support as well. They are already merged into master so you can use the docker image with tag master or compile k6 from source to get it earlier 
Apparently there is a statsd/datadogd to Prometheus exporter https://github.com/prometheus/statsd_exporter which can probably be used with the current master to get metrics from k6 to Prometheus