I share your high regard for C# and the .NET libraries but not your disdain for Java. Java the programming language is pretty ugly but the JVM is robust and there are other languages which compile down to Java bytecode. In your "scrappy startup" scenario I would pick Scala or Clojure long before Python, mainly because I'm skeptical of the idea of using a dynamically typed programming language for large-scale backend development - for human scalability reasons, not performance ones. Personally I'd also have to pass on Windows even in the AAA bigcorp scenario, because I prefer the tooling and open ecosystem around Linux and epoll isn't that much worse than IOCP.

Python supports gradual typing now, and it's made the experience for me much more manageable. Lots of good IDE integration too. It's not a replacement for Java's or Go's (etc...) type system, but it really increases the amount of Python you can support given the human scalability constraints.

I was an exclusive Microsoft developer for a little over 20 years. It wasn’t until I started doing cloud deployments - like the original poster implied - that I started avoiding Windows as often as I could. Once you add Windows to the mix, everything gets worse - startup time, resource requirements, automation, snd costs.

Luckily, you can do C# without having to use Windows with .Net Core.

Ooh, you may be the perfect person to ask a question that I've been wondering about. Is .NET Core on Linux viable yet for serious use? I've done some tinkering with it and gotten a project working on MacOS but I did the development in Visual Studio on Windows. Is it realistic to do your development in Rider, with the open source version of msbuild for CI, and have it perform reasonably on Linux in production, without ever paying Microsoft anything?

The kind of development we do probably wouldn't count as "serious" here on HN, but since the other comment didn't really answer your question, I'll pitch in. We've been developing using .NET Core/Linux/Rider for the past two years. It's been pretty great. Once you get to know the IDE really well, I'd say Rider beats VS in terms of functionality and usability.

.NET Core was developed with CLI usage in mind and common operations (like migrations/boilerplate generation) can be driven from CLI or Rider, you don't need VS for that.

You may have some problems with 3rd-party libraries. Not all of them have been ported to .NET Standard. I'd recommend checking your project's dependencies in advance. (We did have some problems with legacy COM-based cryptographic libraries and had to build a separate "microservice" hosted under Windows to offload this stuff to. COM stuff works fine under .NET Core, but only under Windows (obviously).)

If you are just running a few static Windows servers the slight cost benefit of running Linux for .Net Core is really not that great. If you are doing anything more dynamic where you are rapidly bringing “servers” up and down is where you see the real cost and performance benefits. Of course you can’t run Windows instances with either Fargate or lambda but even with regular ECS (Docker) or autoscaling EC2 instances where you can, Windows costs more, takes more resources, and is slower to launch.

My “Linux deployments” with C# have been Docker and Nginx with Fargate (AWS Serverless Docker) [1] and Lambda. I haven’t had to worry about performance, stability, or scalability. With either technology, you get scalability for free and with Fargate you don’t have to worry about cold starts.

I develop on Windows with Visual Studio and deploy to “Linux”. We use CodeBuild to compile and create the zip file (lambda) or Docker Container (Fargate).

CodeBuild basically is “Serverless builds”. It launches s prebuilt or custom Docker Container and you just run .net core “publish” command line and it gets all of your Nuget packages and then you run your standard packaging commands.

But Rider should be good. I’m a huge fan of R# and you can cross target Linux, Mac and Windows from either host using msbuild.

Curious, how've your cross platform .Net Core experiences been? I've not done much with Linux, but when I was benchmarking writing to MS SQL with the same binary on Linux & Win10, .Net Core had about half the throughput to a remote SQL server instance than Win10. Not sure if others have seen this, but .Net Core seems to run significantly slower on linux vs Windows, in my experience.

Most benchmarks show either similar or better performance overall.

https://stackoverflow.com/questions/44334125/net-core-on-win...

https://robertoprevato.github.io/More-about-Linux-vs-Windows...

But there are reported issues with sql:

https://github.com/dotnet/corefx/issues/24480

Is C# more performant than Java? It was my understanding that HotSpot's JIT performs significantly more optimizations, almost bordering on esoteric magic, compared to the CLR.

I can understand how value types would help a lot, but it is possible to optimize Java to avoid object headers on the heap at great pain, i.e. avoiding classes and doing index arithmetic on flat arrays of values. Value types coming to the JVM will obviously help here.

Curious to hear about other advantages the CLR has.