I'm looking for a free container- or pod-based hosting service that allows inbound raw TCP connections. I don't want to manage a traditional virtual machine or VPS; something similar to a managed container service would be ideal.
I'm currently using a managed platform to run a small Minecraft server written in Go, but its free tier only supports HTTP and HTTPS. I worked around that by running a background bridge that converts the Minecraft Java client's TCP traffic into WebSockets, but I'd rather expose the server directly so players don't need to run an extra script.
The server uses very few resources, and I'm mainly experimenting to see how far I can get without spending anything. Are there providers with a genuinely free container tier that supports TCP ingress? Services that require a credit card even when the usage is free aren't ideal.
3 Answers
The container still has to run on someone's virtualized infrastructure, so avoiding a VM mostly means handing that management to the provider. Also, WebSockets are built on TCP; the distinction here is really between a WebSocket-over-HTTP connection and exposing the Minecraft server's raw TCP protocol directly. A completely free service with persistent networking, public ingress, and no meaningful limits is unlikely, since those resources cost the provider money.
A small cloud VM would probably be the most straightforward solution, even though it doesn't match your preference. Some introductory VM tiers can handle a lightweight server, but availability, billing requirements, and eligibility rules vary. You'd also need to account for latency and limited CPU, since a free instance may perform poorly for multiplayer gaming.
I was hoping to avoid managing a VM, but a small introductory instance may be worth considering if the container options are too restricted.
Azure Container Apps can support TCP ingress and includes a free usage allowance. It isn't as simple to configure as a basic managed app deployment, but it fits the container-based setup better than using a full virtual machine. Make sure to check the current limits and whether your traffic stays within the free quota.

A free allowance can work for testing, but it probably won't be reliable for a public server. Even if the CPU and memory are sufficient, bandwidth limits, sleeping, connection timeouts, or network latency could become the real bottlenecks.