gistfile1.cs

public void Execute(string code, IEnumerable<string> references, IEnumerable<string> namespaces, ScriptPackSession scriptPackSession)
{
    var host = _scriptHostFactory.CreateScriptHost(new ScriptPackManager(scriptPackSession.Contexts));

    foreach (var context in scriptPackSession.Contexts) _scriptEngine.AddReference(context.GetType().Assembly);

    var session = _scriptEngine.CreateSession(host);

    foreach (var reference in references.Union(scriptPackSession.References).Distinct())
        session.AddReference(reference);

    foreach (var @namespace in namespaces.Union(scriptPackSession.Namespaces).Distinct())
        session.ImportNamespace(@namespace);

    Execute(code, session);
}