diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,12 @@
 and this project adheres to the
 [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
-## 0.0.3 - 2023-09-27
+## 0.0.4 - 2026-03-04
+
+* For SHA256 hashes, depend on package `cryptohash-sha256` rather than
+  `crypton` and `memory` (the latter is unmaintained).
+
+## 0.0.3 - 2025-09-27
 
 * Drop support for GHC versions before GHC 8.4.
 * Add `CHANGELOG.md`.
diff --git a/casa-client.cabal b/casa-client.cabal
--- a/casa-client.cabal
+++ b/casa-client.cabal
@@ -1,11 +1,11 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.38.2.
+-- This file has been generated from package.yaml by hpack version 0.39.1.
 --
 -- see: https://github.com/sol/hpack
 
 name:           casa-client
-version:        0.0.3
+version:        0.0.4
 synopsis:       Client for Casa
 description:    Client for Casa (Content-Addressable Storage Archive). See
                 <https://casa.stackage.org/>
@@ -43,11 +43,10 @@
     , casa-types >=0.0.2
     , conduit >=1.3.4.2
     , conduit-extra >=1.3.5
-    , crypton >=0.34
+    , cryptohash-sha256 >=0.11
     , exceptions >=0.10.4
     , http-conduit >=2.3.8
     , http-types >=0.12.3
-    , memory >=0.15.0
     , network-uri >=2.6.4.1
     , resourcet >=1.2.4.3
     , template-haskell >=2.16.0.0
diff --git a/src/Casa/Client.hs b/src/Casa/Client.hs
--- a/src/Casa/Client.hs
+++ b/src/Casa/Client.hs
@@ -25,10 +25,9 @@
 import           Control.Monad.IO.Unlift
                    ( MonadUnliftIO, UnliftIO (..), askUnliftIO )
 import           Control.Monad.Trans.Resource ( MonadResource )
-import qualified Crypto.Hash as Crypto
+import qualified Crypto.Hash.SHA256 as SHA256
 import           Data.Aeson ( FromJSON (..) )
 import qualified Data.Attoparsec.ByteString as Atto
-import qualified Data.ByteArray as Mem
 import           Data.ByteString ( ByteString )
 import qualified Data.ByteString as S
 import qualified Data.ByteString.Builder as SB
@@ -219,4 +218,4 @@
 
 -- | Hash some raw bytes.
 sha256Hash :: ByteString -> ByteString
-sha256Hash = Mem.convert . Crypto.hashWith Crypto.SHA256
+sha256Hash = SHA256.hash