Create preview versions of NuGet packages is a very useful thing when multiple projects depends on it. If your are using FAKE to script your builds, you can increment automatically your NuGets versions. see

I recently modified a build script to automate alpha or beta NuGet versionning with a small module:

open Fake
open System
open System.Text.RegularExpressions

module Mercurial =
  type BranchInfo =
    | Default
    | Pre of name:string

  let getBranch () =
    let (|PrevName|_|) (s:string) =
      let regex = new Regex("^(alpha|beta)\d*$")
      if regex.IsMatch s
      then Some s
      else None
    let (|Branch|_|) = function
      | [{IsError=_;Message="default";Timestamp=_}] -> Some Default
      | [{IsError=_;Message=(PrevName name);Timestamp=_}] -> Some (Pre name)
      | _ -> None

    let success,result =
        (fun info ->
          info.FileName <- "hg"
          info.Arguments <- "branch"
          info.WorkingDirectory <- __SOURCE_DIRECTORY__)
          (TimeSpan.FromSeconds 2.)
    match success, (List.ofSeq result) with
    | true, Branch branch -> branch
    | _ -> Default


So, when the branch name is like “alpha”, “beta”, “alpha1”, “beta10”, etc … I can concat it with the next NuGet version number.

let nugetsVersions name =
    let v =
      NuGetVersion.nextVersion <|
        fun arg ->
            { arg
                    Server=(nugetPublishUrl + "api/v2")
    match Mercurial.getBranch() with
    | Mercurial.BranchInfo.Default -> v
    | Mercurial.BranchInfo.Pre name -> sprintf "%s-%s" v name

nugetsVersions "scrapysharp"
// val version : string = "1.0.1-alpha"