diff --git a/TestAssets/TestProjects/BuildTestPortableProject/Lib.cs b/TestAssets/TestProjects/BuildTestPortableProject/Lib.cs
new file mode 100644
index 000000000..2ac94ca9d
--- /dev/null
+++ b/TestAssets/TestProjects/BuildTestPortableProject/Lib.cs
@@ -0,0 +1,3 @@
+public static class Thingy
+{
+}
diff --git a/TestAssets/TestProjects/BuildTestPortableProject/project.json b/TestAssets/TestProjects/BuildTestPortableProject/project.json
new file mode 100644
index 000000000..43c20c90b
--- /dev/null
+++ b/TestAssets/TestProjects/BuildTestPortableProject/project.json
@@ -0,0 +1,16 @@
+{
+    "dependencies": {
+    },
+    "frameworks": {
+        "net45": {},
+        "netstandardapp1.5": {
+            "imports": [
+                "dnxcore50",
+                "portable-net45+win8"
+            ],
+            "dependencies": {
+                "NETStandard.Library": "1.0.0-rc2-23901"
+            }
+        }
+    }
+}
diff --git a/TestAssets/TestProjects/BuildTestStandaloneProject/Lib.cs b/TestAssets/TestProjects/BuildTestStandaloneProject/Lib.cs
new file mode 100644
index 000000000..2ac94ca9d
--- /dev/null
+++ b/TestAssets/TestProjects/BuildTestStandaloneProject/Lib.cs
@@ -0,0 +1,3 @@
+public static class Thingy
+{
+}
diff --git a/TestAssets/TestProjects/BuildTestStandaloneProject/project.json b/TestAssets/TestProjects/BuildTestStandaloneProject/project.json
new file mode 100644
index 000000000..d8b5d9d86
--- /dev/null
+++ b/TestAssets/TestProjects/BuildTestStandaloneProject/project.json
@@ -0,0 +1,20 @@
+{
+    "dependencies": { },
+    "frameworks": {
+        "netstandardapp1.5": {
+            "imports": [
+                "dnxcore50",
+                "portable-net45+win8"
+            ],
+            "dependencies": {
+                "NETStandard.Library": "1.0.0-rc2-23901"
+            }
+        }
+    },
+    "runtimes": {
+        "win7-x64": {},
+        "osx.10.10-x64": {},
+        "ubuntu.14.04-x64": {},
+        "centos.7-x64": {}
+    }
+}
diff --git a/scripts/dev-dotnet.ps1 b/scripts/dev-dotnet.ps1
index 8b5f1290f..4728a8b7c 100644
--- a/scripts/dev-dotnet.ps1
+++ b/scripts/dev-dotnet.ps1
@@ -6,11 +6,16 @@
 $oldPath = $env:PATH
 try {
     # Put the stage2 output on the front of the path
-    $stage2 = "$PSScriptRoot\..\artifacts\win7-x64\stage2\bin"
+    if(!(Get-Command dotnet -ErrorAction SilentlyContinue)) {
+        throw "You need to have a version of 'dotnet' on your path so we can determine the RID"
+    }
+
+    $rid = dotnet --version | where { $_ -match "^ Runtime Id:\s*(.*)$" } | foreach { $matches[1] } 
+    $stage2 = "$PSScriptRoot\..\artifacts\$rid\stage2\bin"
     if (Test-Path $stage2) {
         $env:PATH="$stage2;$env:PATH"
     } else {
-        Write-Host "You don't have a dev build in the 'artifacts\win7-x64\stage2' folder!"
+        Write-Host "You don't have a dev build in the 'artifacts\$rid\stage2' folder!"
     }
 
     dotnet @args
diff --git a/scripts/dotnet-cli-build/CompileTargets.cs b/scripts/dotnet-cli-build/CompileTargets.cs
index b84fa6452..bbf03cf4f 100644
--- a/scripts/dotnet-cli-build/CompileTargets.cs
+++ b/scripts/dotnet-cli-build/CompileTargets.cs
@@ -45,6 +45,13 @@ namespace Microsoft.DotNet.Cli.Build
             "Microsoft.Extensions.Testing.Abstractions"
         };
 
+        // Updates the stage 2 with recent changes.
+        [Target(nameof(PrepareTargets.Init), nameof(CompileStage2))]
+        public static BuildTargetResult UpdateBuild(BuildTargetContext c)
+        {
+            return c.Success();
+        }
+
         [Target(nameof(PrepareTargets.Init), nameof(CompileCoreHost), nameof(CompileStage1), nameof(CompileStage2))]
         public static BuildTargetResult Compile(BuildTargetContext c)
         {
diff --git a/src/Microsoft.DotNet.Cli.Utils/project.json b/src/Microsoft.DotNet.Cli.Utils/project.json
index 877df020f..625b48bf4 100644
--- a/src/Microsoft.DotNet.Cli.Utils/project.json
+++ b/src/Microsoft.DotNet.Cli.Utils/project.json
@@ -19,8 +19,9 @@
         "netstandard1.3": {
             "imports": "dnxcore50",
             "dependencies": {
-                "NETStandard.Library": "1.0.0-rc2-23901"
+                "NETStandard.Library": "1.0.0-rc2-23901",
+                "System.Diagnostics.Process": "4.1.0-rc2-23901"
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/Microsoft.DotNet.Compiler.Common/Executable.cs b/src/Microsoft.DotNet.Compiler.Common/Executable.cs
index 31f92825f..3aedeedc8 100644
--- a/src/Microsoft.DotNet.Compiler.Common/Executable.cs
+++ b/src/Microsoft.DotNet.Compiler.Common/Executable.cs
@@ -39,11 +39,6 @@ namespace Microsoft.Dotnet.Cli.Compiler.Common
 
         public void MakeCompilationOutputRunnable()
         {
-            if (string.IsNullOrEmpty(_context.RuntimeIdentifier))
-            {
-                throw new InvalidOperationException($"Can not make output runnable for framework {_context.TargetFramework}, because it doesn't have runtime target");
-            }
-
             CopyContentFiles();
             ExportRuntimeAssets();
         }
@@ -72,8 +67,11 @@ namespace Microsoft.Dotnet.Cli.Compiler.Common
         {
             WriteDepsFileAndCopyProjectDependencies(_exporter);
 
-            // TODO: Pick a host based on the RID
-            CoreHost.CopyTo(_runtimeOutputPath, _context.ProjectFile.Name + Constants.ExeSuffix);
+            if (!string.IsNullOrEmpty(_context.RuntimeIdentifier))
+            {
+                // TODO: Pick a host based on the RID
+                CoreHost.CopyTo(_runtimeOutputPath, _context.ProjectFile.Name + Constants.ExeSuffix);
+            }
         }
 
         private void CopyContentFiles()
diff --git a/src/Microsoft.DotNet.ProjectModel/OutputPathsCalculator.cs b/src/Microsoft.DotNet.ProjectModel/OutputPathsCalculator.cs
index aa9c9fb87..fdaa7c5e3 100644
--- a/src/Microsoft.DotNet.ProjectModel/OutputPathsCalculator.cs
+++ b/src/Microsoft.DotNet.ProjectModel/OutputPathsCalculator.cs
@@ -48,12 +48,18 @@ namespace Microsoft.DotNet.ProjectModel
             {
                 if (!string.IsNullOrEmpty(runtimeIdentifier))
                 {
-                    runtimeOutputPath= PathUtility.EnsureTrailingSlash(Path.Combine(compilationOutputPath, runtimeIdentifier));
+                    runtimeOutputPath = PathUtility.EnsureTrailingSlash(Path.Combine(compilationOutputPath, runtimeIdentifier));
+                }
+                else
+                {
+                    // "Runtime" assets (i.e. the deps file) will be dropped to the compilation output path, because
+                    // we are building a RID-less target.
+                    runtimeOutputPath = compilationOutputPath;
                 }
             }
             else
             {
-                runtimeOutputPath= PathUtility.EnsureTrailingSlash(Path.GetFullPath(outputPath));
+                runtimeOutputPath = PathUtility.EnsureTrailingSlash(Path.GetFullPath(outputPath));
             }
 
             var intermediateOutputPath = PathUtility.EnsureTrailingSlash(Path.Combine(
diff --git a/src/Microsoft.DotNet.ProjectModel/Project.cs b/src/Microsoft.DotNet.ProjectModel/Project.cs
index c4a8c4a41..5e187f55b 100644
--- a/src/Microsoft.DotNet.ProjectModel/Project.cs
+++ b/src/Microsoft.DotNet.ProjectModel/Project.cs
@@ -35,7 +35,7 @@ namespace Microsoft.DotNet.ProjectModel
                 return Path.GetDirectoryName(ProjectFilePath);
             }
         }
-        
+
         public AnalyzerOptions AnalyzerOptions { get; set; }
 
         public string Name { get; set; }
@@ -124,12 +124,12 @@ namespace Microsoft.DotNet.ProjectModel
 
         public bool HasRuntimeOutput(string configuration)
         {
-
             var compilationOptions = GetCompilerOptions(targetFramework: null, configurationName: configuration);
 
             // TODO: Make this opt in via another mechanism
             return compilationOptions.EmitEntryPoint.GetValueOrDefault() || IsTestProject;
         }
+
         private CommonCompilerOptions GetCompilerOptions()
         {
             return _defaultCompilerOptions;
diff --git a/src/Microsoft.DotNet.ProjectModel/ProjectContext.cs b/src/Microsoft.DotNet.ProjectModel/ProjectContext.cs
index 9e237ff11..99f869f36 100644
--- a/src/Microsoft.DotNet.ProjectModel/ProjectContext.cs
+++ b/src/Microsoft.DotNet.ProjectModel/ProjectContext.cs
@@ -83,7 +83,7 @@ namespace Microsoft.DotNet.ProjectModel
                         .WithRuntimeIdentifiers(runtimeIdentifiers)
                         .Build();
         }
-        
+
         public static ProjectContextBuilder CreateBuilder(string projectPath, NuGetFramework framework)
         {
             if (projectPath.EndsWith(Project.FileName))
@@ -120,15 +120,12 @@ namespace Microsoft.DotNet.ProjectModel
         /// <summary>
         /// Creates a project context for each target located in the project at <paramref name="projectPath"/>
         /// </summary>
-        public static IEnumerable<ProjectContext> CreateContextForEachTarget(string projectPath)
+        public static IEnumerable<ProjectContext> CreateContextForEachTarget(string projectPath, ProjectReaderSettings settings = null)
         {
-            if (!projectPath.EndsWith(Project.FileName))
-            {
-                projectPath = Path.Combine(projectPath, Project.FileName);
-            }
             var project = ProjectReader.GetProject(projectPath);
 
             return new ProjectContextBuilder()
+                        .WithReaderSettings(settings)
                         .WithProject(project)
                         .BuildAllTargets();
         }
@@ -143,15 +140,20 @@ namespace Microsoft.DotNet.ProjectModel
 
         public ProjectContext CreateRuntimeContext(IEnumerable<string> runtimeIdentifiers)
         {
-            var context = Create(ProjectFile.ProjectFilePath, TargetFramework, runtimeIdentifiers);
-            if (context.RuntimeIdentifier == null)
+            // Check if there are any runtime targets (i.e. are we portable)
+            var standalone = LockFile.Targets
+                .Where(t => t.TargetFramework.Equals(TargetFramework))
+                .Any(t => !string.IsNullOrEmpty(t.RuntimeIdentifier));
+
+            var context = Create(ProjectFile.ProjectFilePath, TargetFramework, standalone ? runtimeIdentifiers : Enumerable.Empty<string>());
+            if (standalone && context.RuntimeIdentifier == null)
             {
+                // We are standalone, but don't support this runtime
                 var rids = string.Join(", ", runtimeIdentifiers);
-                throw new InvalidOperationException($"Can not find runtime target for framework '{TargetFramework}' and RID's '{rids}'. " +
+                throw new InvalidOperationException($"Can not find runtime target for framework '{TargetFramework}' compatible with one of the target runtimes: '{rids}'. " +
                                                     "Possible causes:" + Environment.NewLine +
-                                                    "1. Project is not restored or restore failed - run `dotnet restore`" + Environment.NewLine +
-                                                    "2. Project is not targeting `runable` framework (`netstandardapp*` or `net*`)"
-                                                    );
+                                                    "1. The project has not been restored or restore failed - run `dotnet restore`" + Environment.NewLine +
+                                                    $"2. The project does not list one of '{rids}' in the 'runtimes' section.");
             }
             return context;
         }
diff --git a/src/Microsoft.DotNet.ProjectModel/ProjectReader.cs b/src/Microsoft.DotNet.ProjectModel/ProjectReader.cs
index 2a58b3bd5..39f28ba12 100644
--- a/src/Microsoft.DotNet.ProjectModel/ProjectReader.cs
+++ b/src/Microsoft.DotNet.ProjectModel/ProjectReader.cs
@@ -61,18 +61,20 @@ namespace Microsoft.DotNet.ProjectModel
             return true;
         }
 
-        public static Project GetProject(string projectFile, ProjectReaderSettings settings = null)
-        {
-            return GetProject(projectFile, new List<DiagnosticMessage>(), settings);
-        }
+        public static Project GetProject(string projectPath, ProjectReaderSettings settings = null) => GetProject(projectPath, new List<DiagnosticMessage>(), settings);
 
-        public static Project GetProject(string projectFile, ICollection<DiagnosticMessage> diagnostics, ProjectReaderSettings settings = null)
+        public static Project GetProject(string projectPath, ICollection<DiagnosticMessage> diagnostics, ProjectReaderSettings settings = null)
         {
-            var name = Path.GetFileName(Path.GetDirectoryName(projectFile));
-
-            using (var stream = new FileStream(projectFile, FileMode.Open, FileAccess.Read, FileShare.Read))
+            if (!projectPath.EndsWith(Project.FileName))
             {
-                return new ProjectReader().ReadProject(stream, name, projectFile, diagnostics, settings);
+                projectPath = Path.Combine(projectPath, Project.FileName);
+            }
+
+            var name = Path.GetFileName(Path.GetDirectoryName(projectPath));
+
+            using (var stream = new FileStream(projectPath, FileMode.Open, FileAccess.Read, FileShare.Read))
+            {
+                return new ProjectReader().ReadProject(stream, name, projectPath, diagnostics, settings);
             }
         }
 
@@ -546,7 +548,8 @@ namespace Microsoft.DotNet.ProjectModel
                             analyzerOptions.LanguageId = languageId;
                             break;
 
-                        default:;
+                        default:
+                            ;
                             throw FileFormatException.Create(
                                $"Unrecognized analyzerOption key: {key}",
                                project.ProjectFilePath);
diff --git a/src/dotnet/commands/dotnet-build/CompileContext.cs b/src/dotnet/commands/dotnet-build/CompileContext.cs
index 7e0e43957..de2b43475 100644
--- a/src/dotnet/commands/dotnet-build/CompileContext.cs
+++ b/src/dotnet/commands/dotnet-build/CompileContext.cs
@@ -48,7 +48,7 @@ namespace Microsoft.DotNet.Tools.Build
         {
             CreateOutputDirectories();
 
-            return CompileDendencies(incremental) && CompileRootProject(incremental);
+            return CompileDependencies(incremental) && CompileRootProject(incremental);
         }
 
         private bool CompileRootProject(bool incremental)
@@ -66,7 +66,7 @@ namespace Microsoft.DotNet.Tools.Build
             return success;
         }
 
-        private bool CompileDendencies(bool incremental)
+        private bool CompileDependencies(bool incremental)
         {
             if (_args.ShouldSkipDependencies)
             {
@@ -395,15 +395,7 @@ namespace Microsoft.DotNet.Tools.Build
 
             if (succeeded)
             {
-                if (_rootProject.ProjectFile.HasRuntimeOutput(_args.ConfigValue))
-                {
-                    MakeRunnable();
-                }
-                else if (!string.IsNullOrEmpty(_args.OutputValue))
-                {
-                    var outputPaths = _rootProject.GetOutputPaths(_args.ConfigValue, _args.BuildBasePathValue, _args.OutputValue);
-                    CopyCompilationOutput(outputPaths);
-                }
+                MakeRunnable();
             }
 
             return succeeded;
@@ -428,9 +420,22 @@ namespace Microsoft.DotNet.Tools.Build
         private void MakeRunnable()
         {
             var runtimeContext = _rootProject.CreateRuntimeContext(_args.GetRuntimes());
+            if(_args.PortableMode)
+            {
+                // HACK: Force the use of the portable target
+                runtimeContext = _rootProject;
+            }
+
             var outputPaths = runtimeContext.GetOutputPaths(_args.ConfigValue, _args.BuildBasePathValue, _args.OutputValue);
             var libraryExporter = runtimeContext.CreateExporter(_args.ConfigValue, _args.BuildBasePathValue);
-            CopyCompilationOutput(outputPaths);
+
+            // If we're building for a specific RID, we need to copy the RID-less compilation output into
+            // the RID-specific output dir
+            if (!string.IsNullOrEmpty(runtimeContext.RuntimeIdentifier))
+            {
+                CopyCompilationOutput(outputPaths);
+            }
+
             var executable = new Executable(runtimeContext, outputPaths, libraryExporter);
             executable.MakeCompilationOutputRunnable();
 
diff --git a/src/dotnet/commands/dotnet-compile/CompilerCommandApp.cs b/src/dotnet/commands/dotnet-compile/CompilerCommandApp.cs
index 2c7fa2a0f..9a66f1777 100644
--- a/src/dotnet/commands/dotnet-compile/CompilerCommandApp.cs
+++ b/src/dotnet/commands/dotnet-compile/CompilerCommandApp.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using Microsoft.Dnx.Runtime.Common.CommandLine;
@@ -28,6 +29,7 @@ namespace Microsoft.DotNet.Tools.Compiler
         private CommandOption _runtimeOption;
         private CommandOption _versionSuffixOption;
         private CommandOption _configurationOption;
+        private CommandOption _portableOption;
         private CommandArgument _projectArgument;
         private CommandOption _nativeOption;
         private CommandOption _archOption;
@@ -41,8 +43,8 @@ namespace Microsoft.DotNet.Tools.Compiler
         // resolved values for the options and arguments
         public string ProjectPathValue { get; set; }
         public string BuildBasePathValue { get; set; }
-        public string OutputValue { get; set; }
         public string RuntimeValue { get; set; }
+        public string OutputValue { get; set; }
         public string VersionSuffixValue { get; set; }
         public string ConfigValue { get; set; }
         public bool IsNativeValue { get; set; }
@@ -53,6 +55,7 @@ namespace Microsoft.DotNet.Tools.Compiler
         public bool IsCppModeValue { get; set; }
         public string AppDepSdkPathValue { get; set; }
         public string CppCompilerFlagsValue { get; set; }
+        public bool PortableMode { get; set; }
 
         // workaround: CommandLineApplication is internal therefore I cannot make _app protected so baseclasses can add their own params
         private readonly Dictionary<string, CommandOption> baseClassOptions;
@@ -77,12 +80,15 @@ namespace Microsoft.DotNet.Tools.Compiler
 
             _outputOption = _app.Option("-o|--output <OUTPUT_DIR>", "Directory in which to place outputs", CommandOptionType.SingleValue);
             _buildBasePath = _app.Option("-b|--build-base-path <OUTPUT_DIR>", "Directory in which to place temporary outputs", CommandOptionType.SingleValue);
-            _frameworkOption = _app.Option("-f|--framework <FRAMEWORK>", "Compile a specific framework", CommandOptionType.MultipleValue);
+            _frameworkOption = _app.Option("-f|--framework <FRAMEWORK>", "Compile a specific framework", CommandOptionType.SingleValue);
+            _runtimeOption = _app.Option("-r|--runtime <RUNTIME_IDENTIFIER>", "Produce runtime-specific assets for the specified runtime", CommandOptionType.SingleValue);
             _configurationOption = _app.Option("-c|--configuration <CONFIGURATION>", "Configuration under which to build", CommandOptionType.SingleValue);
-            _runtimeOption = _app.Option("-r|--runtime <RUNTIME_IDENTIFIER>", "Target runtime to publish for", CommandOptionType.SingleValue);
             _versionSuffixOption = _app.Option("--version-suffix <VERSION_SUFFIX>", "Defines what `*` should be replaced with in version field in project.json", CommandOptionType.SingleValue);
             _projectArgument = _app.Argument("<PROJECT>", "The project to compile, defaults to the current directory. Can be a path to a project.json or a project directory");
 
+            // HACK: Allow us to treat a project as though it was portable by ignoring the runtime-specific targets. This is temporary until RID inference is removed from NuGet
+            _portableOption = _app.Option("--portable", "TEMPORARY: Enforces portable build/publish mode", CommandOptionType.NoValue);
+
             // Native Args
             _nativeOption = _app.Option("-n|--native", "Compiles source to native machine code.", CommandOptionType.NoValue);
             _archOption = _app.Option("-a|--arch <ARCH>", "The architecture for which to compile. x64 only currently supported.", CommandOptionType.SingleValue);
@@ -98,6 +104,12 @@ namespace Microsoft.DotNet.Tools.Compiler
         {
             _app.OnExecute(() =>
             {
+                if (_outputOption.HasValue() && !_frameworkOption.HasValue())
+                {
+                    Reporter.Error.WriteLine("When the '--output' option is provided, the '--framework' option must also be provided.");
+                    return 1;
+                }
+
                 // Locate the project and get the name and full path
                 ProjectPathValue = _projectArgument.Value;
                 if (string.IsNullOrEmpty(ProjectPathValue))
@@ -110,6 +122,7 @@ namespace Microsoft.DotNet.Tools.Compiler
                 ConfigValue = _configurationOption.Value() ?? Constants.DefaultConfiguration;
                 RuntimeValue = _runtimeOption.Value();
                 VersionSuffixValue = _versionSuffixOption.Value();
+                PortableMode = _portableOption.HasValue();
 
                 IsNativeValue = _nativeOption.HasValue();
                 ArchValue = _archOption.Value();
@@ -120,8 +133,6 @@ namespace Microsoft.DotNet.Tools.Compiler
                 IsCppModeValue = _cppModeOption.HasValue();
                 CppCompilerFlagsValue = _cppCompilerFlagsOption.Value();
 
-                IEnumerable<ProjectContext> contexts;
-                
                 // Set defaults based on the environment
                 var settings = ProjectReaderSettings.ReadFromEnvironment();
 
@@ -130,29 +141,35 @@ namespace Microsoft.DotNet.Tools.Compiler
                     settings.VersionSuffix = VersionSuffixValue;
                 }
 
-                if (_frameworkOption.HasValue())
+                // Load the project file and construct all the targets
+                var targets = ProjectContext.CreateContextForEachFramework(ProjectPathValue, settings).ToList();
+
+                if (targets.Count == 0)
                 {
-                    contexts = _frameworkOption.Values
-                        .Select(f =>
-                        {
-                            return ProjectContext.CreateBuilder(ProjectPathValue, NuGetFramework.Parse(f))
-                                                 .WithReaderSettings(settings)
-                                                 .Build();
-                        });
-                }
-                else
-                {
-                    if (!string.IsNullOrEmpty(OutputValue))
-                    {
-                        throw new InvalidOperationException($"'{_frameworkOption.LongName}' is required when '{_outputOption.LongName}' is specified");
-                    }
-                    else
-                    {
-                        contexts = ProjectContext.CreateContextForEachFramework(ProjectPathValue, settings);
-                    }
+                    // Project is missing 'frameworks' section
+                    Reporter.Error.WriteLine("Project does not have any frameworks listed in the 'frameworks' section.");
+                    return 1;
                 }
 
-                var success = execute(contexts.ToList(), this);
+                // Filter the targets down based on the inputs
+                if (_frameworkOption.HasValue())
+                {
+                    var fx = NuGetFramework.Parse(_frameworkOption.Value());
+                    targets = targets.Where(t => fx.Equals(t.TargetFramework)).ToList();
+
+                    if (targets.Count == 0)
+                    {
+                        // We filtered everything out
+                        Reporter.Error.WriteLine($"Project does not support framework: {fx.DotNetFrameworkName}.");
+                        return 1;
+                    }
+
+                    Debug.Assert(targets.Count == 1);
+                }
+
+                Debug.Assert(targets.All(t => string.IsNullOrEmpty(t.RuntimeIdentifier)));
+
+                var success = execute(targets, this);
 
                 return success ? 0 : 1;
             });
diff --git a/src/dotnet/commands/dotnet-compile/ManagedCompiler.cs b/src/dotnet/commands/dotnet-compile/ManagedCompiler.cs
index aeb692979..d2b149b31 100644
--- a/src/dotnet/commands/dotnet-compile/ManagedCompiler.cs
+++ b/src/dotnet/commands/dotnet-compile/ManagedCompiler.cs
@@ -9,7 +9,6 @@ using Microsoft.DotNet.Cli.Compiler.Common;
 using Microsoft.DotNet.Cli.Utils;
 using Microsoft.DotNet.ProjectModel;
 using Microsoft.DotNet.ProjectModel.Compilation;
-using Microsoft.DotNet.ProjectModel.Utilities;
 using Microsoft.Extensions.DependencyModel;
 
 namespace Microsoft.DotNet.Tools.Compiler
@@ -161,6 +160,10 @@ namespace Microsoft.DotNet.Tools.Compiler
                 contextVariables.Add(
                     "compile:RuntimeOutputDir",
                     runtimeOutputPath.RuntimeOutputPath.TrimEnd('\\', '/'));
+
+                contextVariables.Add(
+                    "compile:RuntimeIdentifier",
+                    runtimeContext.RuntimeIdentifier);
             }
 
             _scriptRunner.RunScripts(context, ScriptNames.PreCompile, contextVariables);
diff --git a/test/ArgumentForwardingTests/project.json b/test/ArgumentForwardingTests/project.json
index 7175750b5..8b99a663f 100644
--- a/test/ArgumentForwardingTests/project.json
+++ b/test/ArgumentForwardingTests/project.json
@@ -27,5 +27,5 @@
 
     "testRunner": "xunit",
 
-    "scripts": { "precompile": "dotnet build ../ArgumentsReflector/project.json --framework netstandardapp1.5 --output %compile:RuntimeOutputDir%" }
+    "scripts": { "precompile": "dotnet build ../ArgumentsReflector/project.json --framework netstandardapp1.5 --runtime %compile:RuntimeIdentifier% --output %compile:RuntimeOutputDir%" }
 }
diff --git a/test/Microsoft.DotNet.Tools.Tests.Utilities/Assertions/CommandResultAssertions.cs b/test/Microsoft.DotNet.Tools.Tests.Utilities/Assertions/CommandResultAssertions.cs
index 00516044b..3fab175b5 100644
--- a/test/Microsoft.DotNet.Tools.Tests.Utilities/Assertions/CommandResultAssertions.cs
+++ b/test/Microsoft.DotNet.Tools.Tests.Utilities/Assertions/CommandResultAssertions.cs
@@ -60,7 +60,14 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             return new AndConstraint<CommandResultAssertions>(this);
         }
 
-        public AndConstraint<CommandResultAssertions> StdOutMatchPattern(string pattern, RegexOptions options = RegexOptions.None)
+        public AndConstraint<CommandResultAssertions> HaveStdOutContaining(string pattern)
+        {
+            Execute.Assertion.ForCondition(_commandResult.StdOut.Contains(pattern))
+                .FailWith(AppendDiagnosticsTo($"The command output did not contain expected result: {pattern}{Environment.NewLine}"));
+            return new AndConstraint<CommandResultAssertions>(this);
+        }
+
+        public AndConstraint<CommandResultAssertions> HaveStdOutMatching(string pattern, RegexOptions options = RegexOptions.None)
         {
             Execute.Assertion.ForCondition(Regex.Match(_commandResult.StdOut, pattern, options).Success)
                 .FailWith(AppendDiagnosticsTo($"Matching the command output failed. Pattern: {pattern}{Environment.NewLine}"));
@@ -74,6 +81,20 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             return new AndConstraint<CommandResultAssertions>(this);
         }
 
+        public AndConstraint<CommandResultAssertions> HaveStdErrContaining(string pattern)
+        {
+            Execute.Assertion.ForCondition(_commandResult.StdErr.Contains(pattern))
+                .FailWith(AppendDiagnosticsTo($"The command error output did not contain expected result: {pattern}{Environment.NewLine}"));
+            return new AndConstraint<CommandResultAssertions>(this);
+        }
+
+        public AndConstraint<CommandResultAssertions> HaveStdErrMatching(string pattern, RegexOptions options = RegexOptions.None)
+        {
+            Execute.Assertion.ForCondition(Regex.Match(_commandResult.StdErr, pattern, options).Success)
+                .FailWith(AppendDiagnosticsTo($"Matching the command error output failed. Pattern: {pattern}{Environment.NewLine}"));
+            return new AndConstraint<CommandResultAssertions>(this);
+        }
+
         public AndConstraint<CommandResultAssertions> NotHaveStdOut()
         {
             Execute.Assertion.ForCondition(string.IsNullOrEmpty(_commandResult.StdOut))
diff --git a/test/Microsoft.DotNet.Tools.Tests.Utilities/Commands/BuildCommand.cs b/test/Microsoft.DotNet.Tools.Tests.Utilities/Commands/BuildCommand.cs
index 93102cf12..da059a1fe 100644
--- a/test/Microsoft.DotNet.Tools.Tests.Utilities/Commands/BuildCommand.cs
+++ b/test/Microsoft.DotNet.Tools.Tests.Utilities/Commands/BuildCommand.cs
@@ -11,23 +11,25 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
     public sealed class BuildCommand : TestCommand
     {
         private Project _project;
-        private string _projectPath;
-        private string _outputDirectory;
-        private string _buidBasePathDirectory;
-        private string _configuration;
-        private string _framework;
-        private string _versionSuffix;
-        private bool _noHost;
-        private bool _native;
-        private string _architecture;
-        private string _ilcArgs;
-        private string _ilcPath;
-        private string _appDepSDKPath;
-        private bool _nativeCppMode;
-        private string _cppCompilerFlags;
-        private bool _buildProfile;
-        private bool _noIncremental;
-        private bool _noDependencies;
+        private readonly string _projectPath;
+        private readonly string _outputDirectory;
+        private readonly string _buidBasePathDirectory;
+        private readonly string _configuration;
+        private readonly string _framework;
+        private readonly string _versionSuffix;
+        private readonly bool _noHost;
+        private readonly bool _native;
+        private readonly string _architecture;
+        private readonly string _ilcArgs;
+        private readonly string _ilcPath;
+        private readonly string _appDepSDKPath;
+        private readonly bool _nativeCppMode;
+        private readonly string _cppCompilerFlags;
+        private readonly bool _buildProfile;
+        private readonly bool _noIncremental;
+        private readonly bool _noDependencies;
+        private readonly string _runtime;
+        private readonly bool _forcePortable;
 
         private string OutputOption
         {
@@ -39,6 +41,16 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             }
         }
 
+        private string ForcePortableOption
+        {
+            get
+            {
+                return _forcePortable ?
+                    "--portable" :
+                    string.Empty;
+            }
+        }
+
         private string BuildBasePathOption
         {
             get
@@ -67,7 +79,7 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
                                            $"--framework {_framework}";
             }
         }
-        
+
         private string VersionSuffixOption
         {
             get
@@ -98,6 +110,16 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             }
         }
 
+        private string RuntimeOption
+        {
+            get
+            {
+                return _runtime == string.Empty ?
+                    "" :
+                    $"--runtime {_runtime}";
+            }
+        }
+
         private string ArchitectureOption
         {
             get
@@ -194,6 +216,7 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             string buidBasePath="",
             string configuration="",
             string framework="",
+            string runtime="",
             string versionSuffix="",
             bool noHost=false,
             bool native=false,
@@ -205,7 +228,8 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             string cppCompilerFlags="",
             bool buildProfile=true,
             bool noIncremental=false,
-            bool noDependencies=false
+            bool noDependencies=false,
+            bool forcePortable=false
             )
             : base("dotnet")
         {
@@ -217,6 +241,7 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             _configuration = configuration;
             _versionSuffix = versionSuffix;
             _framework = framework;
+            _runtime = runtime;
             _noHost = noHost;
             _native = native;
             _architecture = architecture;
@@ -228,6 +253,7 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
             _buildProfile = buildProfile;
             _noIncremental = noIncremental;
             _noDependencies = noDependencies;
+            _forcePortable = forcePortable;
         }
 
         public override CommandResult Execute(string args = "")
@@ -251,7 +277,7 @@ namespace Microsoft.DotNet.Tools.Test.Utilities
 
         private string BuildArgs()
         {
-            return $"{BuildProfile} {NoDependencies} {NoIncremental} \"{_projectPath}\" {OutputOption} {BuildBasePathOption} {ConfigurationOption} {FrameworkOption} {VersionSuffixOption} {NoHostOption} {NativeOption} {ArchitectureOption} {IlcArgsOption} {IlcPathOption} {AppDepSDKPathOption} {NativeCppModeOption} {CppCompilerFlagsOption}";
+            return $"{BuildProfile} {ForcePortableOption} {NoDependencies} {NoIncremental} \"{_projectPath}\" {OutputOption} {BuildBasePathOption} {ConfigurationOption} {FrameworkOption} {RuntimeOption} {VersionSuffixOption} {NoHostOption} {NativeOption} {ArchitectureOption} {IlcArgsOption} {IlcPathOption} {AppDepSDKPathOption} {NativeCppModeOption} {CppCompilerFlagsOption}";
         }
     }
 }
diff --git a/test/dotnet-build.Tests/BuildInvalidArgumentsTests.cs b/test/dotnet-build.Tests/BuildInvalidArgumentsTests.cs
new file mode 100644
index 000000000..15a38b24b
--- /dev/null
+++ b/test/dotnet-build.Tests/BuildInvalidArgumentsTests.cs
@@ -0,0 +1,55 @@
+using System.IO;
+using Microsoft.DotNet.Tools.Test.Utilities;
+using Xunit;
+
+namespace Microsoft.DotNet.Tools.Builder.Tests
+{
+    public class BuildInvalidArgumentsTests : TestBase
+    {
+        [Fact]
+        public void ErrorOccursWhenBuildingPortableProjectToSpecificOutputPathWithoutSpecifyingFramework()
+        {
+            var testInstance = TestAssetsManager.CreateTestInstance("BuildTestPortableProject")
+                .WithLockFiles();
+
+            var result = new BuildCommand(
+                    projectPath: testInstance.TestRoot,
+                    output: Path.Combine(testInstance.TestRoot, "out"))
+                .ExecuteWithCapturedOutput();
+
+            result.Should().Fail();
+            result.Should().HaveStdErrContaining("When the '--output' option is provided, the '--framework' option must also be provided.");
+        }
+
+        [Fact]
+        public void ErrorOccursWhenBuildingPortableProjectAndSpecifyingFrameworkThatProjectDoesNotSupport()
+        {
+            var testInstance = TestAssetsManager.CreateTestInstance("BuildTestPortableProject")
+                .WithLockFiles();
+
+            var result = new BuildCommand(
+                    projectPath: testInstance.TestRoot,
+                    output: Path.Combine(testInstance.TestRoot, "out"),
+                    framework: "sl40")
+                .ExecuteWithCapturedOutput();
+
+            result.Should().Fail();
+            result.Should().HaveStdErrContaining("Project does not support framework: Silverlight,Version=v4.0.");
+        }
+
+        [Fact]
+        public void ErrorOccursWhenBuildingStandaloneProjectToSpecificOutputPathWithoutSpecifyingFramework()
+        {
+            var testInstance = TestAssetsManager.CreateTestInstance("BuildTestStandaloneProject")
+                .WithLockFiles();
+
+            var result = new BuildCommand(
+                    projectPath: testInstance.TestRoot,
+                    output: Path.Combine(testInstance.TestRoot, "out"))
+                .ExecuteWithCapturedOutput();
+
+            result.Should().Fail();
+            result.Should().HaveStdErrContaining("When the '--output' option is provided, the '--framework' option must also be provided.");
+        }
+    }
+}
diff --git a/test/dotnet-build.Tests/BuildPortableTests.cs b/test/dotnet-build.Tests/BuildPortableTests.cs
new file mode 100644
index 000000000..6ecfad1f1
--- /dev/null
+++ b/test/dotnet-build.Tests/BuildPortableTests.cs
@@ -0,0 +1,44 @@
+using System.IO;
+using Microsoft.DotNet.Tools.Test.Utilities;
+using Xunit;
+
+namespace Microsoft.DotNet.Tools.Builder.Tests
+{
+    public class BuildPortableTests : TestBase
+    {
+        [Fact]
+        public void BuildingAPortableProjectProducesDepsFile()
+        {
+            var testInstance = TestAssetsManager.CreateTestInstance("BuildTestPortableProject")
+                .WithLockFiles();
+
+            var result = new BuildCommand(
+                projectPath: testInstance.TestRoot,
+                forcePortable: true)
+                .ExecuteWithCapturedOutput();
+
+            result.Should().Pass();
+
+            var outputBase = new DirectoryInfo(Path.Combine(testInstance.TestRoot, "bin", "Debug"));
+
+            var netstandardappOutput = outputBase.Sub("netstandardapp1.5");
+            var fxSubdirs = new[] {
+                netstandardappOutput,
+                outputBase.Sub("net45")
+            };
+
+            foreach(var fxSubdir in fxSubdirs)
+            {
+                fxSubdir.Should()
+                    .Exist().And
+                    .HaveFiles(new[]
+                    {
+                        "BuildTestPortableProject.dll",
+                        "BuildTestPortableProject.pdb"
+                    });
+            }
+
+            netstandardappOutput.Should().HaveFile("BuildTestPortableProject.deps");
+        }
+    }
+}
diff --git a/test/dotnet-build.Tests/BuildProjectToProjectTests.cs b/test/dotnet-build.Tests/BuildProjectToProjectTests.cs
index c3b55a740..8735a84a6 100644
--- a/test/dotnet-build.Tests/BuildProjectToProjectTests.cs
+++ b/test/dotnet-build.Tests/BuildProjectToProjectTests.cs
@@ -75,7 +75,7 @@ namespace Microsoft.DotNet.Tools.Builder.Tests
 
             // second build with no dependencies and no incremental; only the root rebuilds
             var result2 = BuildProject(noDependencies: true, noIncremental: true);
-            result2.Should().StdOutMatchPattern("Compiling.*L0.*");
+            result2.Should().HaveStdOutMatching("Compiling.*L0.*");
 
             AssertResultDoesNotContainStrings(result2, dependencies);
 
diff --git a/test/dotnet-publish.Tests/Microsoft.DotNet.Tools.Publish.Tests.cs b/test/dotnet-publish.Tests/Microsoft.DotNet.Tools.Publish.Tests.cs
index c1dcfeda3..22562e818 100644
--- a/test/dotnet-publish.Tests/Microsoft.DotNet.Tools.Publish.Tests.cs
+++ b/test/dotnet-publish.Tests/Microsoft.DotNet.Tools.Publish.Tests.cs
@@ -188,7 +188,7 @@ namespace Microsoft.DotNet.Tools.Publish.Tests
             var publishCommand = new PublishCommand(testProject);
             var result = publishCommand.ExecuteWithCapturedOutput();
 
-            result.Should().StdOutMatchPattern("\nprepublish_output( \\?[^%]+\\?){5}.+\npostpublish_output( \\?[^%]+\\?){5}", RegexOptions.Singleline);
+            result.Should().HaveStdOutMatching("\nprepublish_output( \\?[^%]+\\?){5}.+\npostpublish_output( \\?[^%]+\\?){5}", RegexOptions.Singleline);
             result.Should().Pass();
         }
     }