diff --git a/Sources/SRP/Array.swift b/Sources/SRP/Array.swift
index 8f2a181..0061ac5 100644
--- a/Sources/SRP/Array.swift
+++ b/Sources/SRP/Array.swift
@@ -18,6 +18,16 @@ extension Array where Element: FixedWidthInteger {
     }
 }
 
+extension Array where Element == UInt8 {
+    func pad(to size: Int) -> [UInt8] {
+        let padSize = size - self.count
+        guard padSize > 0 else { return self }
+        // create prefix and return prefix + data
+        let prefix: [UInt8] = (1...padSize).reduce([]) { result,_ in return result + [0] }
+        return prefix + self
+    }
+}
+
 /// xor together the contents of two byte arrays
 func ^ (lhs: [UInt8], rhs: [UInt8]) -> [UInt8] {
     precondition(lhs.count == rhs.count, "Arrays are required to be the same size")
diff --git a/Sources/SRP/srp.swift b/Sources/SRP/srp.swift
index b4dce89..b923ea6 100644
--- a/Sources/SRP/srp.swift
+++ b/Sources/SRP/srp.swift
@@ -1,16 +1,6 @@
 import BigNum
 import Crypto
 
-extension Array where Element == UInt8 {
-    func pad(to size: Int) -> [UInt8] {
-        let padSize = size - self.count
-        guard padSize > 0 else { return self }
-        // create prefix and return prefix + data
-        let prefix: [UInt8] = (1...padSize).reduce([]) { result,_ in return result + [0] }
-        return prefix + self
-    }
-}
-
 /// Contains common code used by both client and server SRP code
 public struct SRP<H: HashFunction> {