Hi Pawel, we have a TypeScript type provider that we use internally to generate a few of the extensions (~5 out of 50) and this is part of the Insider Pro subscription already. It uses an older TypeScript syntax (v0.9 I believe), but works for most libraries that have their TypeScript declarations published.

For the record, our largest extensions are generated via other means, mostly from documentation, and the majority of the rest are WIG-based.

Have a look at our Support page for plans that we have for start-ups and other orgs. The Start-up and Enterprise plans come with training, mentoring, and architectural or project review, to get you started on the right track the fastest way possible. You can use this support time any way you want, including help with custom extensions, etc.

We might consider a "mini Start-up" plan for teams of 1-3 developers that includes training, etc., or one that includes Insider Basic or Pro subscriptions. Drop us a line from the Consulting or Training pages if this might be of interest.

As for plans, we just rolled out WebSharper 3.3 with uniform client-server JSON serialization today, making it much easier to develop robust service-based backends and consuming clients. Next up is a unified, reactive HTML syntax that provides better code sharing between client and server, compatibility with the current sitelet HTML languages (Html.Client and Html.Server), and much more flexible templating capabilities, among others. This is targeted in WebSharper 3.4 due in August with a set of other enhancements, such as proxies for the new upcoming F# 4.0 standard library APIs, etc.

Further plans include a faster compiler and C# support, and we will be blogging about these in the coming months extensively.