Yeah, I don’t like that the article itself treats building the DB seed data, etc, into the Firecracker VM image like this is impossible to do in Docker. The techniques are good things to do — but it’s very tenuous how the techniques are connected to Firecracker.
I’ve do all of the above using multi-layered Docker files and a cron CI job to rebuild the base integration test image every 6 hours. Sure if you need the isolation, Firecracker is the way to go. But if you invest primarily in container shenanigans to speed up CI with Docker, it’s not too much extra work to wrap it in a Firecracker VM, plain QEMU, or whatever once you start wanting more isolation.
Also, maybe I’m holding it wrong but Docker in Docker had not bitten us yet on our GitHub action runners.
I’ve do all of the above using multi-layered Docker files and a cron CI job to rebuild the base integration test image every 6 hours. Sure if you need the isolation, Firecracker is the way to go. But if you invest primarily in container shenanigans to speed up CI with Docker, it’s not too much extra work to wrap it in a Firecracker VM, plain QEMU, or whatever once you start wanting more isolation.
Also, maybe I’m holding it wrong but Docker in Docker had not bitten us yet on our GitHub action runners.