diff --git a/.github/.keepalive b/.github/.keepalive
deleted file mode 100644
index ff4cc78..0000000
--- a/.github/.keepalive
+++ /dev/null
@@ -1 +0,0 @@
-2022-03-16T07:47:36.812Z
diff --git a/lib/main.js b/lib/main.js
index f3fa013..a4431da 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -21,6 +21,7 @@
 // MODULES //
 
 var isString = require( '@stdlib/assert-is-string' ).isPrimitive;
+var format = require( '@stdlib/string-format' );
 var ALIAS_TO_SIGNATURE = require( './../data/data.json' );
 
 
@@ -41,7 +42,7 @@ function signature( alias ) {
 	var out;
 	var i;
 	if ( !isString( alias ) ) {
-		throw new TypeError( 'invalid argument. Must provide a string. Value: `' + alias + '`.' );
+		throw new TypeError( format( 'invalid argument. Must provide a string. Value: `%s`.', alias ) );
 	}
 	out = [];
 	for ( i = 0; i < ALIAS_TO_SIGNATURE.length; i++ ) {
diff --git a/package.json b/package.json
index dcedc1f..f441fa9 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,8 @@
   "dependencies": {
     "@stdlib/assert-is-string": "^0.0.x",
     "@stdlib/cli-ctor": "^0.0.x",
-    "@stdlib/fs-read-file": "^0.0.x"
+    "@stdlib/fs-read-file": "^0.0.x",
+    "@stdlib/string-format": "^0.0.x"
   },
   "devDependencies": {
     "@stdlib/assert-is-browser": "^0.0.x",