<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFrameworks>netstandard1.6;net462</TargetFrameworks>
    <VersionPrefix>1.0.2</VersionPrefix>
    <VersionSuffix>alpha</VersionSuffix>
    <GeneratePackageOnBuild>True</GeneratePackageOnBuild>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Newtonsoft.Json" Version="10.0.2" />
    <PackageReference Include="protobuf-net" Version="2.1.0" />
  </ItemGroup>

</Project>

myassembly.1.0.2.alpha.nupkg

dotnet build myassembly.csproj

myassembly.1.0.0.nupkg