.NET 4.0 CTP and EF CTP - is it good enough for production code?

Question

I'm very interested in using 4.0 framework and also the Entity Framework 4.0. Currently .net 4.0 is in CTP and I'm EF 4.0 is in CTP Preview. I will not be coding for a few more months, but i'm not so sure that either .net 4.0 or EF 4.0 will be RTM by then.

My questions:

1) Regarding Microsoft Products, is CTP usually stable enough for production?

2) If I use CTP initially and then want to upgrade to RTM when it's available should i expect a lot of pain in the upgrade? or is RTM usually "backwards compatible" with the CTP?

Answer 1

For .NET 4.0 neither the CTP nor the currently available Beta 1 of .NET 4.0 is licensed for production use.

Microsoft's previous behavior has that Beta 2 is normally under their Go Live licensing which allows for some production use. There is a comment from Somasegar on this blog post that says that they will release a Go Live version "at a later date."

I can only speak for .NET 4.0 and not EF, but we have been writing production code with it for a while and while there were some breaking changes between CTP and Beta 1 there do not look to be as many breaking changes between Beta 1 and Beta 2.

Answer 2

Often beta and CTP products aren't even licensed for production use, regardless of stability. You should check what the licence says before anything else - assuming you care about legality, of course.

There will often be a fair amount of change between CTP and release, but less between beta and release, and even less between RC and release.

Btw, .NET 4.0 is in beta 1, not CTP.

Answer 3

As others noted, both the beta and CTP licenses do not allow deployment on a prod server.

On the other hand, as MS will delay the release of both VS 2010 and the .net fx 4.0, the release candidate versions will have their licensing changed to allow for use in production.

More info here.