diff --git a/lib/auth.h b/lib/auth.h
index 5d8da7b6..42d4580d 100644
--- a/lib/auth.h
+++ b/lib/auth.h
@@ -1,3 +1,4 @@
+#pragma once
 #include <string>
 #include <openssl/rsa.h>
 #include <openssl/x509.h>
diff --git a/lib/base64.h b/lib/base64.h
index 2358ae98..6adc5123 100644
--- a/lib/base64.h
+++ b/lib/base64.h
@@ -1,3 +1,4 @@
+#pragma once
 #include <string>
 
 /// Holds base64 decoding and encoding functions.
diff --git a/lib/config.h b/lib/config.h
index acf3fb17..04b9b732 100644
--- a/lib/config.h
+++ b/lib/config.h
@@ -1,6 +1,7 @@
 /// \file config.h
 /// Contains generic function headers for managing configuration.
 
+#pragma once
 #include <string>
 
 #define STRINGIFY(x) #x
diff --git a/lib/json.h b/lib/json.h
index f8d47aec..3c01ae02 100644
--- a/lib/json.h
+++ b/lib/json.h
@@ -1,5 +1,6 @@
 /// \file json.h Holds all JSON-related headers.
 
+#pragma once
 #include <string>
 #include <deque>
 #include <map>
diff --git a/lib/procs.h b/lib/procs.h
index c10620b8..ceabca3d 100644
--- a/lib/procs.h
+++ b/lib/procs.h
@@ -1,6 +1,7 @@
 /// \file procs.h
 /// Contains generic function headers for managing processes.
 
+#pragma once
 #include <unistd.h>
 #include <string>
 #include <map>