diff --git a/main.fnl b/main.fnl
index 16af05c..be5f69e 100644
--- a/main.fnl
+++ b/main.fnl
@@ -65,6 +65,8 @@
     (assoc (parse-args rest) :server-private-key (slurp f))
     ["--challenge-password" f & rest]
     (assoc (parse-args rest) :challenge-password (read-line f))
+    ["--sign-file" f & rest]
+    (assoc (parse-args rest) :sign-and-exit (slurp f))
     [bind-address] { : bind-address }
     _ {}))
 
@@ -72,6 +74,8 @@
        (doto
            (parse-args arg)
          (case
+             {:sign-and-exit pathname }
+           true
              {: ca-certificate : ca-private-key
               : server-certificate : server-private-key
               : challenge-password : bind-address}
@@ -141,7 +145,17 @@
             :ctx (ssl-context)
             }))))
 
-(let [s (new-server)]
-  (ncall (s:listen))
-  (print "server ready")
-  (ncall (s:loop)))
+(fn run-server []
+  (let [s (new-server)]
+    (ncall (s:listen))
+    (print "server ready")
+    (ncall (s:loop))))
+
+(fn sign-text [s]
+  (let [crt (new-crt (csr.new s))]
+    (print (crt:toPEM))))
+
+
+(if options.sign-and-exit
+    (sign-text options.sign-and-exit)
+    (run-server))