diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,9 @@
 # Changelog
 
+- 0.2.2 (2025-02-28)
+  * Various optimizations, including roughly 2x faster decoding
+    performance.
+
 - 0.2.1 (2025-01-07)
   * Removes the 'primitive' dependency.
 
diff --git a/lib/Data/ByteString/Base32.hs b/lib/Data/ByteString/Base32.hs
--- a/lib/Data/ByteString/Base32.hs
+++ b/lib/Data/ByteString/Base32.hs
@@ -54,7 +54,41 @@
 bech32_charset = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"
 
 word5 :: Word8 -> Maybe Word8
-word5 w8 = fmap fi (BS.elemIndex w8 bech32_charset)
+word5 = \case
+  113 -> pure $! 0
+  112 -> pure $! 1
+  122 -> pure $! 2
+  114 -> pure $! 3
+  121 -> pure $! 4
+  57  -> pure $! 5
+  120 -> pure $! 6
+  56  -> pure $! 7
+  103 -> pure $! 8
+  102 -> pure $! 9
+  50  -> pure $! 10
+  116 -> pure $! 11
+  118 -> pure $! 12
+  100 -> pure $! 13
+  119 -> pure $! 14
+  48  -> pure $! 15
+  115 -> pure $! 16
+  51  -> pure $! 17
+  106 -> pure $! 18
+  110 -> pure $! 19
+  53  -> pure $! 20
+  52  -> pure $! 21
+  107 -> pure $! 22
+  104 -> pure $! 23
+  99  -> pure $! 24
+  101 -> pure $! 25
+  54  -> pure $! 26
+  109 -> pure $! 27
+  117 -> pure $! 28
+  97  -> pure $! 29
+  55  -> pure $! 30
+  108 -> pure $! 31
+  _   -> Nothing
+{-# INLINE word5 #-}
 
 arrange :: Word32 -> Word8 -> BSB.Builder
 arrange w32 w8 =
diff --git a/lib/Data/ByteString/Bech32/Internal.hs b/lib/Data/ByteString/Bech32/Internal.hs
--- a/lib/Data/ByteString/Bech32/Internal.hs
+++ b/lib/Data/ByteString/Bech32/Internal.hs
@@ -48,7 +48,7 @@
 
 -- naive word5 -> base32
 as_base32 :: BS.ByteString -> BS.ByteString
-as_base32 = BS.map (BS.index bech32_charset . fi)
+as_base32 = BS.map (BU.unsafeIndex bech32_charset . fi)
 
 polymod :: BS.ByteString -> Word32
 polymod = BS.foldl' alg 1 where
diff --git a/ppad-bech32.cabal b/ppad-bech32.cabal
--- a/ppad-bech32.cabal
+++ b/ppad-bech32.cabal
@@ -1,6 +1,6 @@
 cabal-version:      3.0
 name:               ppad-bech32
-version:            0.2.1
+version:            0.2.2
 synopsis:           bech32 and bech32m encoding/decoding, per BIPs 173 & 350.
 license:            MIT
 license-file:       LICENSE