Provisioning and deployment of applications to IoT devices

Question

I have a small growing fleet of IoT devices (upboards). They are all connected via ethernet to a server. Each device runs the same set of applications (java, python, nginx, ffmpeg) with their respective configuration. These devices are the "production" devices.

I have a single development device on which I prototype new applications, change configurations or modify application code.

The IoT devices and server both run CentOS 8.

What would be recommended ways of managing the fleet and deploying the most up to date code to all of the devices, preferably with some form of version control. My first idea would be containerise everything and orchestrate it with something like swarm or kubernetes but I feel that is just too much overkill.