diff --git a/rlimit_nonposix.go b/rlimit_nonposix.go
index 198c9d9f8..fbd58a745 100644
--- a/rlimit_nonposix.go
+++ b/rlimit_nonposix.go
@@ -1,4 +1,4 @@
-// +build windows plan9
+// +build windows plan9 nacl
 
 package caddy
 
diff --git a/rlimit_posix.go b/rlimit_posix.go
index a270e1f2b..90e1568b3 100644
--- a/rlimit_posix.go
+++ b/rlimit_posix.go
@@ -1,4 +1,4 @@
-// +build !windows,!plan9
+// +build !windows,!plan9,!nacl
 
 package caddy
 
diff --git a/sigtrap_nonposix.go b/sigtrap_nonposix.go
index 0b2e6d3ed..96f68119d 100644
--- a/sigtrap_nonposix.go
+++ b/sigtrap_nonposix.go
@@ -1,4 +1,4 @@
-// +build windows plan9
+// +build windows plan9 nacl
 
 package caddy
 
diff --git a/sigtrap_posix.go b/sigtrap_posix.go
index 65dcdd726..0ba0b33e9 100644
--- a/sigtrap_posix.go
+++ b/sigtrap_posix.go
@@ -1,4 +1,4 @@
-// +build !windows,!plan9
+// +build !windows,!plan9,!nacl
 
 package caddy