This works if the github urls are always in the same form

i.e. without the ".git" suffix

NuKeeper.GitHub/GitHubRepository.cs

@@ -3,21 +3,36 @@
 
 namespace NuKeeper.GitHub
 {
-    public class GitHubRepository : Abstractions.CollaborationModels.Repository
+    public class GitHubRepository : Repository
     {
         public GitHubRepository(Octokit.Repository repository)
         : base(
             repository.Name,
             repository.Archived,
             repository.Permissions != null ?
                 new UserPermissions(repository.Permissions.Admin, repository.Permissions.Push, repository.Permissions.Pull) : null,
-            new Uri(repository.CloneUrl),
+            GithubUri(repository.CloneUrl),
             new User(repository.Owner.Login, repository.Owner.Name, repository.Owner.Email),
             repository.Fork,
             repository.Parent != null ?
                 new GitHubRepository(repository.Parent) : null
             )
         {
         }
+
+        private static Uri GithubUri(string value)
+        {
+            if (string.IsNullOrWhiteSpace(value))
+            {
+                return null;
+            }
+
+            if (value.EndsWith(".git", StringComparison.OrdinalIgnoreCase))
+            {
+                value = value.Substring(0, value.Length - 4);
+            }
+
+            return new Uri(value, UriKind.Absolute);
+        }
     }
 }