diff --git a/Sources/CryptoKitten/MD5.swift b/Sources/CryptoKitten/MD5.swift
index 08a231c..b67687d 100644
--- a/Sources/CryptoKitten/MD5.swift
+++ b/Sources/CryptoKitten/MD5.swift
@@ -32,7 +32,11 @@ fileprivate let k: [UInt32] = [ 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
 fileprivate let chunkSize = 64
 
 public final class MD5 : Hash {
-    public static let littleEndian = true
+    #if arch(s390x)
+        public static let littleEndian = false
+    #else
+        public static let littleEndian = true
+    #endif
     public static let chunkSize = 64
     public static let digestSize = 16
     
@@ -76,7 +80,11 @@ public final class MD5 : Hash {
         buffer.reserveCapacity(16)
         
         func convert(_ int: UInt32) -> [UInt8] {
-            let int = int.littleEndian
+            #if arch(s390x)
+                let int = int.bigEndian
+            #else
+                let int = int.littleEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),
@@ -115,7 +123,11 @@ public final class MD5 : Hash {
                 g = (7 &* i) % 16
             }
             
-            Mg = pointer.advanced(by: g << 2).withMemoryRebound(to: UInt32.self, capacity: 1, { $0.pointee })
+            #if arch(s390x)
+                Mg = UInt32(littleEndian: pointer.advanced(by: g << 2).withMemoryRebound(to: UInt32.self, capacity: 1, { $0.pointee }))
+            #else
+                Mg = pointer.advanced(by: g << 2).withMemoryRebound(to: UInt32.self, capacity: 1, { $0.pointee })
+            #endif
             
             F = F &+ a1 &+ k[i] &+ Mg
             a1 = d1
diff --git a/Sources/CryptoKitten/SHA1.swift b/Sources/CryptoKitten/SHA1.swift
index ac5144c..f9a2e1b 100644
--- a/Sources/CryptoKitten/SHA1.swift
+++ b/Sources/CryptoKitten/SHA1.swift
@@ -1,7 +1,11 @@
 public final class SHA1 : Hash {
     public static let digestSize = 20
     public static let chunkSize = 64
-    public static let littleEndian = false
+    #if arch(s390x)
+        public static let littleEndian = true
+    #else
+        public static let littleEndian = false
+    #endif
     
     var h0: UInt32 = 0x67452301
     var h1: UInt32 = 0xEFCDAB89
@@ -40,7 +44,11 @@ public final class SHA1 : Hash {
         buffer.reserveCapacity(20)
         
         func convert(_ int: UInt32) -> [UInt8] {
-            let int = int.bigEndian
+            #if arch(s390x)
+                let int = int.littleEndian
+            #else
+                let int = int.bigEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),
@@ -61,14 +69,22 @@ public final class SHA1 : Hash {
     public init() {}
     
     public func update(pointer: UnsafePointer<UInt8>) {
-        var w = pointer.withMemoryRebound(to: UInt32.self, capacity: 16, { pointer in
-            return [
-                pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
-                pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
-                pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
-                pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
-            ]
-        })
+        #if arch(s390x)
+            var w : [UInt32] = []
+            w.reserveCapacity(16)
+            for index in stride(from: 0, to: 64, by: 4) {
+                w.append(UInt32(bigEndian: pointer.advanced(by: index).withMemoryRebound(to: UInt32.self, capacity: 1, { $0.pointee })))
+            }
+        #else
+            var w = pointer.withMemoryRebound(to: UInt32.self, capacity: 16, { pointer in
+                return [
+                    pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
+                    pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
+                    pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
+                    pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
+                ]
+            })
+        #endif
 
         w.reserveCapacity(80)
 
diff --git a/Sources/CryptoKitten/SHA2_32Base.swift b/Sources/CryptoKitten/SHA2_32Base.swift
index 088c515..c88747e 100644
--- a/Sources/CryptoKitten/SHA2_32Base.swift
+++ b/Sources/CryptoKitten/SHA2_32Base.swift
@@ -29,14 +29,22 @@ internal protocol SHA2_32 : Hash {
 
 extension SHA2_32 {
     public func update(pointer: UnsafePointer<UInt8>) {
-        var w = pointer.withMemoryRebound(to: UInt32.self, capacity: 16, { pointer in
-            return [
-                pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
-                pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
-                pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
-                pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
-                ]
-        })
+        #if arch(s390x)
+            var w : [UInt32] = []
+            w.reserveCapacity(16)
+            for index in stride(from: 0, to: 64, by: 4) {
+                w.append(UInt32(bigEndian: pointer.advanced(by: index).withMemoryRebound(to: UInt32.self, capacity: 1, { $0.pointee })))
+            }
+        #else
+            var w = pointer.withMemoryRebound(to: UInt32.self, capacity: 16, { pointer in
+                return [
+                    pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
+                    pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
+                    pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
+                    pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
+                    ]
+            })
+        #endif
         
         w.reserveCapacity(64)
         
diff --git a/Sources/CryptoKitten/SHA2_32Implementations.swift b/Sources/CryptoKitten/SHA2_32Implementations.swift
index 2edb17b..35af27e 100644
--- a/Sources/CryptoKitten/SHA2_32Implementations.swift
+++ b/Sources/CryptoKitten/SHA2_32Implementations.swift
@@ -1,5 +1,9 @@
 public final class SHA256 : SHA2_32 {
-    public static let littleEndian = false
+    #if arch(s390x)
+        public static let littleEndian = true
+    #else
+        public static let littleEndian = false
+    #endif
     public static let digestSize = 32
     public static let chunkSize = 64
     
@@ -16,7 +20,11 @@ public final class SHA256 : SHA2_32 {
         buffer.reserveCapacity(32)
         
         func convert(_ int: UInt32) -> [UInt8] {
-            let int = int.bigEndian
+            #if arch(s390x)
+                let int = int.littleEndian
+            #else
+                let int = int.bigEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),
@@ -70,7 +78,11 @@ public final class SHA256 : SHA2_32 {
 }
 
 public final class SHA224 : SHA2_32 {
-    public static let littleEndian = false
+    #if arch(s390x)
+        public static let littleEndian = true
+    #else
+        public static let littleEndian = false
+    #endif
     public static let digestSize = 28
     public static let chunkSize = 64
     
@@ -98,7 +110,11 @@ public final class SHA224 : SHA2_32 {
         buffer.reserveCapacity(28)
         
         func convert(_ int: UInt32) -> [UInt8] {
-            let int = int.bigEndian
+            #if arch(s390x)
+                let int = int.littleEndian
+            #else
+                let int = int.bigEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),
diff --git a/Sources/CryptoKitten/SHA2_64Base.swift b/Sources/CryptoKitten/SHA2_64Base.swift
index ddf9315..af9631d 100644
--- a/Sources/CryptoKitten/SHA2_64Base.swift
+++ b/Sources/CryptoKitten/SHA2_64Base.swift
@@ -37,14 +37,22 @@ internal protocol SHA2_64 : Hash {
 
 extension SHA2_64 {
     public func update(pointer: UnsafePointer<UInt8>) {
-        var w = pointer.withMemoryRebound(to: UInt64.self, capacity: 16, { pointer in
-            return [
-                pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
-                pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
-                pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
-                pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
-                ]
-        })
+        #if arch(s390x)
+            var w : [UInt64] = []
+            w.reserveCapacity(16)
+            for index in stride(from: 0, to: 128, by: 8) {
+                w.append(UInt64(bigEndian: pointer.advanced(by: index).withMemoryRebound(to: UInt64.self, capacity: 1, { $0.pointee })))
+            }
+        #else
+            var w = pointer.withMemoryRebound(to: UInt64.self, capacity: 16, { pointer in
+                return [
+                    pointer[0].bigEndian, pointer[1].bigEndian, pointer[2].bigEndian, pointer[3].bigEndian,
+                    pointer[4].bigEndian, pointer[5].bigEndian, pointer[6].bigEndian, pointer[7].bigEndian,
+                    pointer[8].bigEndian, pointer[9].bigEndian, pointer[10].bigEndian, pointer[11].bigEndian,
+                    pointer[12].bigEndian, pointer[13].bigEndian, pointer[14].bigEndian, pointer[15].bigEndian,
+                    ]
+            })
+        #endif
         
         w.reserveCapacity(64)
         
diff --git a/Sources/CryptoKitten/SHA2_64Implementations.swift b/Sources/CryptoKitten/SHA2_64Implementations.swift
index a2efefc..7ab10fe 100644
--- a/Sources/CryptoKitten/SHA2_64Implementations.swift
+++ b/Sources/CryptoKitten/SHA2_64Implementations.swift
@@ -1,5 +1,9 @@
 public final class SHA512 : SHA2_64 {
-    public static let littleEndian = false
+    #if arch(s390x)
+        public static let littleEndian = true
+    #else
+        public static let littleEndian = false
+    #endif
     public static let digestSize = 64
     public static let chunkSize = 128
     
@@ -16,7 +20,11 @@ public final class SHA512 : SHA2_64 {
         buffer.reserveCapacity(32)
         
         func convert(_ int: UInt64) -> [UInt8] {
-            let int = int.bigEndian
+            #if arch(s390x)
+                let int = int.littleEndian
+            #else
+                let int = int.bigEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),
@@ -75,7 +83,11 @@ public final class SHA512 : SHA2_64 {
 
 
 public final class SHA384: SHA2_64 {
-    public static let littleEndian = false
+    #if arch(s390x)
+        public static let littleEndian = true
+    #else
+        public static let littleEndian = false
+    #endif
     public static let digestSize = 48
     public static let chunkSize = 128
     
@@ -92,7 +104,11 @@ public final class SHA384: SHA2_64 {
         buffer.reserveCapacity(32)
         
         func convert(_ int: UInt64) -> [UInt8] {
-            let int = int.bigEndian
+            #if arch(s390x)
+                let int = int.littleEndian
+            #else
+                let int = int.bigEndian
+            #endif
             return [
                 UInt8(int & 0xff),
                 UInt8((int >> 8) & 0xff),