diff --git a/nimcrypto.nimble b/nimcrypto.nimble
index 9e0e664..65088ef 100644
--- a/nimcrypto.nimble
+++ b/nimcrypto.nimble
@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.5.2"
+version       = "0.5.3"
 author        = "Eugene Kabanov"
 description   = "Nim cryptographic library"
 license       = "MIT"
diff --git a/nimcrypto/blake2.nim b/nimcrypto/blake2.nim
index 3c6506f..55b7bc7 100644
--- a/nimcrypto/blake2.nim
+++ b/nimcrypto/blake2.nim
@@ -139,8 +139,8 @@ else:
     B2S_G(v, 3, 4,  9, 14, m[Sigma[n][14]], m[Sigma[n][15]])
 
 proc blake2Transform(ctx: var Blake2bContext, last: bool) {.inline.} =
-  var v: array[16, uint64]
-  var m: array[16, uint64]
+  var v {.noinit.}: array[16, uint64]
+  var m {.noinit.}: array[16, uint64]
 
   when nimvm:
     for i in 0 ..< 8:
@@ -201,8 +201,8 @@ proc blake2Transform(ctx: var Blake2bContext, last: bool) {.inline.} =
     ctx.h[7] = ctx.h[7] xor (v[7] xor v[7 + 8])
 
 proc blake2Transform(ctx: var Blake2sContext, last: bool) {.inline.} =
-  var v: array[16, uint32]
-  var m: array[16, uint32]
+  var v {.noinit.}: array[16, uint32]
+  var m {.noinit.}: array[16, uint32]
 
   when nimvm:
     for i in 0 ..< 8:
diff --git a/nimcrypto/keccak.nim b/nimcrypto/keccak.nim
index 1d2c4fd..f5ad9f2 100644
--- a/nimcrypto/keccak.nim
+++ b/nimcrypto/keccak.nim
@@ -231,9 +231,10 @@ else:
     a[0] = a[0] xor RNDC[r]
 
 proc keccakTransform(data: var array[200, byte]) {.inline.} =
-  var bc: array[5, uint64]
-  var st: array[25, uint64]
-  var t: uint64
+  var
+    bc {.noinit.}: array[5, uint64]
+    st {.noinit.}: array[25, uint64]
+    t: uint64
 
   when nimvm:
     for i in 0 ..< len(st):
diff --git a/nimcrypto/pbkdf2.nim b/nimcrypto/pbkdf2.nim
index 4f9ef34..466883e 100644
--- a/nimcrypto/pbkdf2.nim
+++ b/nimcrypto/pbkdf2.nim
@@ -34,7 +34,6 @@ proc pbkdf2*[T, M, N](ctx: var HMAC[T], password: openarray[M],
     md: array[int(ctx.sizeDigest), byte]
     ctr: uint32
     glength: int
-    olength: int
     bytesWrite: int
 
   when not((M is byte) or (M is char)):
@@ -43,12 +42,17 @@ proc pbkdf2*[T, M, N](ctx: var HMAC[T], password: openarray[M],
   when not((N is byte) or (N is char)):
     {.fatal: "Choosen salt type is not supported!".}
 
+  when (sizeof(int) != 8) and (sizeof(int) != 4):
+    {.fatal: "Choosen architecture is not supported!".}
+
   ctr = 1
   glength = 0
-  when sizeof(int) == 8:
-    olength = min(len(output), int(0xFFFF_FFFF)) # 2^32 - 1
-  elif sizeof(int) == 4:
-    olength = len(output)
+  let olength =
+    when sizeof(int) == 8:
+      min(len(output), int(0xFFFF_FFFF)) # 2^32 - 1
+    else:
+      len(output)
+
   while glength < olength:
     beStore32(counter, 0, ctr)
     ctx.init(password)
@@ -68,7 +72,7 @@ proc pbkdf2*[T, M, N](ctx: var HMAC[T], password: openarray[M],
     glength = glength + bytesWrite
     ctr = ctr + 1
   ctx.clear()
-  result = int(glength)
+  int(glength)
 
 proc pbkdf2*[T, M, N](ctx: var HMAC[T], password: openarray[M],
                       salt: openarray[N], c: int,
@@ -85,11 +89,9 @@ proc pbkdf2*[T, M, N](ctx: var HMAC[T], password: openarray[M],
   ##
   ## Returns number of bytes stored on success, or 0 on error.
   if outlen == -1:
-    result = pbkdf2(ctx, password, salt, c,
-                    output.toOpenArray(0, len(output) - 1))
+    pbkdf2(ctx, password, salt, c, output.toOpenArray(0, len(output) - 1))
   else:
-    result = pbkdf2(ctx, password, salt, c,
-                    output.toOpenArray(0, outlen))
+    pbkdf2(ctx, password, salt, c, output.toOpenArray(0, outlen))
 
 proc pbkdf2*[T, M](hashtype: typedesc, password: openarray[T],
                    salt: openarray[M], c: int,
@@ -103,7 +105,9 @@ proc pbkdf2*[T, M](hashtype: typedesc, password: openarray[T],
   ## ``outlen``   - length of bytes to be stored.
   ##
   ## Returns sequence of bytes.
+  var res: seq[byte]
   if outlen > 0:
     var ctx: HMAC[hashtype]
-    result = newSeq[byte](outlen)
-    discard pbkdf2(ctx, password, salt, c, result)
+    res.setLen(outlen)
+    discard pbkdf2(ctx, password, salt, c, res)
+  res
diff --git a/nimcrypto/rijndael.nim b/nimcrypto/rijndael.nim
index 6e34341..d09e260 100644
--- a/nimcrypto/rijndael.nim
+++ b/nimcrypto/rijndael.nim
@@ -270,7 +270,7 @@ when sizeof(int) == 4:
     swap8(q[3], q[7])
 
   proc subWord(x: uint32): uint32 =
-    var q: array[8, uint32]
+    var q {.noinit.}: array[8, uint32]
     q[0] = x
     q[1] = x
     q[2] = x
@@ -461,7 +461,7 @@ when sizeof(int) == 4:
 
   proc encrypt*(ctx: RijndaelContext, input: openarray[byte],
                 output: var openarray[byte]) =
-    var q: array[8, uint32]
+    var q {.noinit.}: array[8, uint32]
     q[0] = leLoad32(input, 0)
     q[2] = leLoad32(input, 4)
     q[4] = leLoad32(input, 8)
@@ -489,7 +489,7 @@ when sizeof(int) == 4:
 
   proc decrypt*(ctx: RijndaelContext, input: openarray[byte],
                 output: var openarray[byte]) =
-    var q: array[8, uint32]
+    var q {.noinit.}: array[8, uint32]
     q[0] = leLoad32(input, 0)
     q[2] = leLoad32(input, 4)
     q[4] = leLoad32(input, 8)
diff --git a/nimcrypto/ripemd.nim b/nimcrypto/ripemd.nim
index baa22c1..3498c25 100644
--- a/nimcrypto/ripemd.nim
+++ b/nimcrypto/ripemd.nim
@@ -475,7 +475,7 @@ proc ripemd128Transform(state: var array[4, uint32], data: openarray[byte]) =
     bbb = state[1]
     ccc = state[2]
     ddd = state[3]
-    X: array[16, uint32]
+    X {.noinit.}: array[16, uint32]
 
   X[0] = leLoad32(data, 0); X[1] = leLoad32(data, 4)
   X[2] = leLoad32(data, 8); X[3] = leLoad32(data, 12)
@@ -512,7 +512,7 @@ proc ripemd256Transform(state: var array[8, uint32], data: openarray[byte]) =
     bbb = state[5]
     ccc = state[6]
     ddd = state[7]
-    X: array[16, uint32]
+    X {.noinit.}: array[16, uint32]
 
   X[0] = leLoad32(data, 0); X[1] = leLoad32(data, 4)
   X[2] = leLoad32(data, 8); X[3] = leLoad32(data, 12)
@@ -559,7 +559,7 @@ proc ripemd160Transform(state: var array[5, uint32],
     ccc = state[2]
     ddd = state[3]
     eee = state[4]
-    X: array[16, uint32]
+    X {.noinit.}: array[16, uint32]
 
   X[0] = leLoad32(data, 0); X[1] = leLoad32(data, 4)
   X[2] = leLoad32(data, 8); X[3] = leLoad32(data, 12)
@@ -602,7 +602,7 @@ proc ripemd320Transform(state: var array[10, uint32],
     ccc = state[7]
     ddd = state[8]
     eee = state[9]
-    X: array[16, uint32]
+    X {.noinit.}: array[16, uint32]
 
   X[0] = leLoad32(data, 0); X[1] = leLoad32(data, 4)
   X[2] = leLoad32(data, 8); X[3] = leLoad32(data, 12)
diff --git a/nimcrypto/sha.nim b/nimcrypto/sha.nim
index fae4cda..3a3570e 100644
--- a/nimcrypto/sha.nim
+++ b/nimcrypto/sha.nim
@@ -82,7 +82,7 @@ proc sha1Transform[T: bchar](ctx: var Sha1Context,
                              offset: int) {.noinit, inline.} =
   var
     A, B, C, D, E: uint32
-    arr: array[16, uint32]
+    arr {.noinit.}: array[16, uint32]
 
   A = ctx.h[0]
   B = ctx.h[1]
@@ -227,14 +227,15 @@ proc update*(ctx: var Sha1Context, pbytes: ptr byte,
 
 proc finish*(ctx: var Sha1Context,
              data: var openarray[byte]): uint {.inline, discardable.} =
-  var onebyte: array[1, byte]
-  var pad: array[8, byte]
+  let
+    one80 = [0x80'u8]
+    one00 = [0x00'u8]
+  var
+    pad {.noinit.}: array[8, byte]
   beStore64(pad, 0, uint64(ctx.size shl 3))
-  onebyte[0] = 0x80'u8
-  update(ctx, onebyte)
-  onebyte[0] = 0x00'u8
+  update(ctx, one80)
   while (ctx.size and 63'u64) != (64 - 8):
-    update(ctx, onebyte)
+    update(ctx, one00)
   update(ctx, pad)
   if len(data) >= int(ctx.sizeDigest):
     result = ctx.sizeDigest
diff --git a/nimcrypto/sha2.nim b/nimcrypto/sha2.nim
index 08d5537..9fa97bf 100644
--- a/nimcrypto/sha2.nim
+++ b/nimcrypto/sha2.nim
@@ -234,8 +234,9 @@ template ROUND512(a, b, c, d, e, f, g, h, z) =
   h = t0 + t1
 
 proc sha256Transform(state: var array[8, uint32], data: openarray[byte]) =
-  var t0, t1: uint32
-  var W: array[64, uint32]
+  var
+    t0, t1: uint32
+    W {.noinit.}: array[64, uint32]
 
   W[0] = beLoad32(data, 0); W[1] = beLoad32(data, 4);
   W[2] = beLoad32(data, 8); W[3] = beLoad32(data, 12)
@@ -336,8 +337,9 @@ proc sha256Transform(state: var array[8, uint32], data: openarray[byte]) =
   state[7] = state[7] + s7
 
 proc sha512Transform(state: var array[8, uint64], data: openarray[byte]) =
-  var t0, t1: uint64
-  var W: array[80, uint64]
+  var
+    t0, t1: uint64
+    W {.noinit.}: array[80, uint64]
 
   W[0] = beLoad64(data, 0); W[1] = beLoad64(data, 8);
   W[2] = beLoad64(data, 16); W[3] = beLoad64(data, 24)