diff --git a/build/FileWatcher.shade b/build/FileWatcher.shade
new file mode 100644
index 0000000000..f2d93fa010
--- /dev/null
+++ b/build/FileWatcher.shade
@@ -0,0 +1,122 @@
+use namespace="System.Collections.Concurrent"
+
+functions
+    @{
+        public class FileWatcher
+        {
+            private readonly HashSet<string> _files = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+            private readonly ConcurrentDictionary<string, HashSet<string>> _directories = new ConcurrentDictionary<string, HashSet<string>>(StringComparer.OrdinalIgnoreCase);
+
+            private readonly FileSystemWatcher _watcher;
+
+            public FileWatcher(string path)
+            {
+                _watcher = new FileSystemWatcher(path);
+                _watcher.IncludeSubdirectories = true;
+                _watcher.EnableRaisingEvents = true;
+
+                _watcher.Changed += OnWatcherChanged;
+                _watcher.Renamed += OnRenamed;
+                _watcher.Deleted += OnWatcherChanged;
+                _watcher.Created += OnWatcherChanged;
+            }
+
+            public event Action<string> OnChanged;
+
+            public void WatchDirectory(string path, string extension)
+            {
+                var extensions = _directories.GetOrAdd(path, _ => new HashSet<string>(StringComparer.OrdinalIgnoreCase));
+
+                extensions.Add(extension);
+            }
+
+            public bool WatchFile(string path)
+            {
+                return _files.Add(path);
+            }
+            public void Dispose()
+            {
+                _watcher.Dispose();
+            }
+
+            public bool ReportChange(string newPath, WatcherChangeTypes changeType)
+            {
+                return ReportChange(oldPath: null, newPath: newPath, changeType: changeType);
+            }
+
+            public bool ReportChange(string oldPath, string newPath, WatcherChangeTypes changeType)
+            {
+                if (HasChanged(oldPath, newPath, changeType))
+                {
+                    if (oldPath != null)
+                    {
+                        Trace.TraceInformation("{0} -> {1}", oldPath, newPath);
+                    }
+                    else
+                    {
+                        Trace.TraceInformation("{0} -> {1}", changeType, newPath);
+                    }
+
+                    if (OnChanged != null)
+                    {
+                        OnChanged(newPath);
+                    }
+
+                    return true;
+                }
+
+                return false;
+            }
+
+            private void OnRenamed(object sender, RenamedEventArgs e)
+            {
+                ReportChange(e.OldFullPath, e.FullPath, e.ChangeType);
+            }
+
+            private void OnWatcherChanged(object sender, FileSystemEventArgs e)
+            {
+                ReportChange(e.FullPath, e.ChangeType);
+            }
+
+            private bool HasChanged(string oldPath, string newPath, WatcherChangeTypes changeType)
+            {
+                // File changes
+                if (_files.Contains(newPath) || 
+                    (oldPath != null && _files.Contains(oldPath)))
+                {
+                    return true;
+                }
+
+                HashSet<string> extensions;
+                if (_directories.TryGetValue(newPath, out extensions) ||
+                    _directories.TryGetValue(Path.GetDirectoryName(newPath), out extensions))
+                {
+                    string extension = Path.GetExtension(newPath);
+
+                    if (String.IsNullOrEmpty(extension))
+                    {
+                        // Assume it's a directory
+                        if (changeType == WatcherChangeTypes.Created || 
+                            changeType == WatcherChangeTypes.Renamed)
+                        {
+                            foreach (var e in extensions)
+                            {
+                                WatchDirectory(newPath, e);
+                            }
+                        }
+                        else if(changeType == WatcherChangeTypes.Deleted)
+                        {
+                            return true;
+                        }
+
+                        // Ignore anything else
+                        return false;
+                    }
+
+                    return extensions.Contains(extension);
+                }
+
+                return false;
+            }
+        }
+    }
\ No newline at end of file
diff --git a/build/_k-generate-projects.shade b/build/_k-generate-projects.shade
index 8a50d94abb..7dfa97f9d7 100644
--- a/build/_k-generate-projects.shade
+++ b/build/_k-generate-projects.shade
@@ -17,11 +17,16 @@ k-generate-projects
 solutionPath='' 
     Required. Path to the solution directory
 
+skipNet45='false'
+    Optional. Skip net45 project regeneration
+
 */}
 
 content var='net45' include href='net45.txt'
 content var='k10' include href='k10.txt'
 
+default skipNet45='${false}'
+
 @{
     ProjectGenerator.Logger = Log;
 
@@ -30,6 +35,11 @@ content var='k10' include href='k10.txt'
         { "k10", k10 }
     };
 
+    if(skipNet45)
+    {
+        templates.Remove("net45");
+    }
+
     ProjectGenerator.MakeProjects(solutionPath, templates);
 }
 
@@ -245,9 +255,17 @@ functions
 
                 foreach (var pair in configs)
                 {
+                    var targetFramework = pair.Key;
+                    
+                    string projectTemplate;
+                    if(!templates.TryGetValue(targetFramework, out projectTemplate))
+                    {
+                        Warn("Skipping project generation for " + projectName + " - " + targetFramework);
+                        continue;
+                    }
+
                     var allPackageReferences = new Dictionary<string, string>(packageReferences);
 
-                    var targetFramework = pair.Key;
                     var props = (IDictionary<string, object>)pair.Value;
 
                     var specificCompilationOptions = GetObject(props, "compilationOptions") ?? compilationOptions ?? new Dictionary<string, object>();
@@ -294,7 +312,7 @@ functions
                         }
                     }
 
-                    var template = templates[targetFramework]
+                    var template = projectTemplate
                                        .Replace("{ProjectGuid}", id)
                                        .Replace("{Name}", projectName)
                                        .Replace("{Defines}", String.Join(";", defines))
@@ -359,7 +377,7 @@ functions
                                                "Microsoft.Net.ApplicationHost.dll");
 
                 var klrSwitches = configType == "k10" ? "--core45" : "--net45";
-                var args = klrSwitches + " " + appHostPath + " " + projectRoot + " --nobin";
+                var args = klrSwitches + " " + appHostPath + " --nobin " + projectRoot;
                 
                 return String.Format(@"<StartAction>Program</StartAction>
                          <StartProgram>{0}</StartProgram>
diff --git a/build/_k-standard-goals.shade b/build/_k-standard-goals.shade
index af57415b1a..399d0535bd 100644
--- a/build/_k-standard-goals.shade
+++ b/build/_k-standard-goals.shade
@@ -2,6 +2,7 @@ use namespace="System"
 use namespace="System.IO"
 use import="Files"
 use import="BuildEnv"
+use import="FileWatcher"
 
 default BASE_DIR='${Directory.GetCurrentDirectory()}'
 default TARGET_DIR='${Path.Combine(BASE_DIR, "artifacts")}'
@@ -34,7 +35,53 @@ default TEST_DIR='${Path.Combine(TARGET_DIR, "test")}'
 #nuget-install target='install' description='Copy NuGet packages to local repo'
   nuget-local-publish sourcePackagesDir='${BUILD_DIR}'
 
+
+#watch
+  @{
+    var watcher = new FileWatcher(BASE_DIR);
+
+    foreach (var file in Directory.EnumerateFiles(BASE_DIR, "*.json", SearchOption.AllDirectories))
+    {
+        watcher.WatchFile(file);
+    }
+
+    foreach (var file in Directory.EnumerateFiles(BASE_DIR, "*.cs", SearchOption.AllDirectories))
+    {
+        watcher.WatchFile(file);
+    }
+
+    foreach (var dir in Directory.EnumerateDirectories(BASE_DIR, "*.*", SearchOption.AllDirectories))
+    {
+        watcher.WatchDirectory(dir, ".cs");
+        watcher.WatchDirectory(dir, ".json");
+    }
+
+    watcher.OnChanged += path => 
+    {
+      Log.Info("Change detected in " + path);
+      bool restore = path.EndsWith("project.json");
+
+      try
+      {
+        UpdateProjects(BASE_DIR, restore);
+      }
+      catch (Exception ex)
+      {
+        Log.Warn(ex.Message);
+      }
+
+      Log.Info("Waiting for changes...");
+    };
+
+    Log.Info("Waiting for changes...");
+    Console.ReadLine();
+  }
+
 functions @{
     string E(string key) { return Environment.GetEnvironmentVariable(key); }
     void E(string key, string value) { Environment.SetEnvironmentVariable(key, value); }
 }
+
+macro name='UpdateProjects' basePath='string' restore='bool'
+    k command='restore' prefetch='${false}' if='restore'
+    k-generate-projects solutionPath='${basePath}' skipNet45='${!restore}'
\ No newline at end of file
diff --git a/build/_k.shade b/build/_k.shade
index 292f0bc9a1..94e0c75f30 100644
--- a/build/_k.shade
+++ b/build/_k.shade
@@ -11,9 +11,14 @@ kProgram='...'
 
 command=''
 
+prefetch='true'
+    May be passed if fetching k from nuget is required before running
+
 */}
 
-nuget-install package='ProjectK' outputDir='packages' extra='-pre' once='ProjectK-NuGet'
+default prefetch='${true}'
+
+nuget-install package='ProjectK' outputDir='packages' extra='-pre' once='ProjectK-NuGet' if='prefetch'
 
 @{
     Func<string, long> getVersion = version => {