Pass your own Docker image for cloud builds

[tophtucker]

It’d be nice if here you could pass a URL to a Docker image to be used for your cloud build, so you could install whatever languages and software you want. Like an option here:

[PawelStadnicki]

I would like to have the option to use .NET along with its related features, so this functionality is very much appreciated.
I believe the Docker image should not be limited to the Enterprise tier, as it also already supports on-premises deployments

[mythmon]

@PawelStadnicki Thanks for the interest! It's nice to see what people are using Framework with.

Until we add this feature, you might consider making a pull request to https://github.com/observablehq/framework-runtime to add the runtime that you are interested in. I don't have a lot of experience with .NET, so I'm not sure if it would be compatible, but if it is then we'd welcome the addition.

[PawelStadnicki]

Thanks, @mythmon!
I’m currently evaluating the Observable Framework both on Observable Cloud and by deploying it to various Azure hosting environments.
I will share my final findings with you shortly (no later than this month).

In general, .NET Core is cross-platform, and I expect all I need is:

FROM mcr.microsoft.com/dotnet/sdk:8.0 (or soon 9.0)
ENV PATH "$PATH:/root/.dotnet/tools"

This setup takes approximately 230 MB (not counting any Nuget package that may be used by data loaders).
It would be ideal to have this as part of the standard Docker image for the Framework.

What I’m particularly exploring further with the Observable Framework is the .NET → JS transpilation. I noticed that the "tags" feature might be opening soon (#967), potentially enabling other languages (like C# and F#) to be transpiled to JS and used in notebook cells.

That might require one or a few more lines in the Dockerfile and I believe it should not be part of the general docker image but rather sth that can be added on the "Build settings" as suggested by the ticked author. I will provide an update soon.