diff --git a/cmd/coordinator/builders.go b/cmd/coordinator/builders.go
index 1344414..68fd3cc 100644
--- a/cmd/coordinator/builders.go
+++ b/cmd/coordinator/builders.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/coordinator.go b/cmd/coordinator/coordinator.go
index 26eacdd..94da768 100644
--- a/cmd/coordinator/coordinator.go
+++ b/cmd/coordinator/coordinator.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 // The coordinator runs the majority of the Go build system.
 //
 // It is responsible for finding build work and executing it,
diff --git a/cmd/coordinator/coordinator_test.go b/cmd/coordinator/coordinator_test.go
index dd78e2c..bd14218 100644
--- a/cmd/coordinator/coordinator_test.go
+++ b/cmd/coordinator/coordinator_test.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/dash.go b/cmd/coordinator/dash.go
index 752cb15..b93fee8 100644
--- a/cmd/coordinator/dash.go
+++ b/cmd/coordinator/dash.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 // Code interacting with build.golang.org ("the dashboard").
 
 package main
diff --git a/cmd/coordinator/debug.go b/cmd/coordinator/debug.go
index 212372e..a980741 100644
--- a/cmd/coordinator/debug.go
+++ b/cmd/coordinator/debug.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/gce.go b/cmd/coordinator/gce.go
index 09fbae0..5901cae 100644
--- a/cmd/coordinator/gce.go
+++ b/cmd/coordinator/gce.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 // Code interacting with Google Compute Engine (GCE) and
 // a GCE implementation of the BuildletPool interface.
 
diff --git a/cmd/coordinator/kube.go b/cmd/coordinator/kube.go
index 82fa2a3..795bf88 100644
--- a/cmd/coordinator/kube.go
+++ b/cmd/coordinator/kube.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/log.go b/cmd/coordinator/log.go
index 153dc0d..9482f0c 100644
--- a/cmd/coordinator/log.go
+++ b/cmd/coordinator/log.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/metrics.go b/cmd/coordinator/metrics.go
index 3da7238..f9d89b0 100644
--- a/cmd/coordinator/metrics.go
+++ b/cmd/coordinator/metrics.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/remote.go b/cmd/coordinator/remote.go
index d216b61..86732fa 100644
--- a/cmd/coordinator/remote.go
+++ b/cmd/coordinator/remote.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 // Code related to remote buildlets. See x/build/remote-buildlet.txt
 
 package main // import "golang.org/x/build/cmd/coordinator"
diff --git a/cmd/coordinator/remote_test.go b/cmd/coordinator/remote_test.go
index 38f3d3c..4f010a8 100644
--- a/cmd/coordinator/remote_test.go
+++ b/cmd/coordinator/remote_test.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/reverse.go b/cmd/coordinator/reverse.go
index 306c0b3..413db18 100644
--- a/cmd/coordinator/reverse.go
+++ b/cmd/coordinator/reverse.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 /*
diff --git a/cmd/coordinator/sched.go b/cmd/coordinator/sched.go
index 095e024..2393370 100644
--- a/cmd/coordinator/sched.go
+++ b/cmd/coordinator/sched.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/status.go b/cmd/coordinator/status.go
index 15aa056..3d072ab 100644
--- a/cmd/coordinator/status.go
+++ b/cmd/coordinator/status.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/cmd/coordinator/status_test.go b/cmd/coordinator/status_test.go
index b8b4c21..edca9c6 100644
--- a/cmd/coordinator/status_test.go
+++ b/cmd/coordinator/status_test.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/bzr.go b/vcs-test/vcweb/bzr.go
index 4064fb3..468d6d7 100644
--- a/vcs-test/vcweb/bzr.go
+++ b/vcs-test/vcweb/bzr.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/fossil.go b/vcs-test/vcweb/fossil.go
index ea7d9c4..2640137 100644
--- a/vcs-test/vcweb/fossil.go
+++ b/vcs-test/vcweb/fossil.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/git.go b/vcs-test/vcweb/git.go
index ef08c07..5396fad 100644
--- a/vcs-test/vcweb/git.go
+++ b/vcs-test/vcweb/git.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/hg.go b/vcs-test/vcweb/hg.go
index 4f2d5ce..18cc1e8 100644
--- a/vcs-test/vcweb/hg.go
+++ b/vcs-test/vcweb/hg.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/load.go b/vcs-test/vcweb/load.go
index 630f5df..b9aa357 100644
--- a/vcs-test/vcweb/load.go
+++ b/vcs-test/vcweb/load.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/main.go b/vcs-test/vcweb/main.go
index 0425192..781dced 100644
--- a/vcs-test/vcweb/main.go
+++ b/vcs-test/vcweb/main.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/svn.go b/vcs-test/vcweb/svn.go
index b959a8e..7e98179 100644
--- a/vcs-test/vcweb/svn.go
+++ b/vcs-test/vcweb/svn.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (
diff --git a/vcs-test/vcweb/tls.go b/vcs-test/vcweb/tls.go
index 42ab28b..b22ffb6 100644
--- a/vcs-test/vcweb/tls.go
+++ b/vcs-test/vcweb/tls.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build linux
+
 package main
 
 import (