diff --git a/pkgs/applications/networking/instant-messengers/telegram/telegram-desktop/unwrapped.nix b/pkgs/applications/networking/instant-messengers/telegram/telegram-desktop/unwrapped.nix
index 24e825cf86f2..6b0db9daf026 100644
--- a/pkgs/applications/networking/instant-messengers/telegram/telegram-desktop/unwrapped.nix
+++ b/pkgs/applications/networking/instant-messengers/telegram/telegram-desktop/unwrapped.nix
@@ -15,7 +15,7 @@
   qtwayland,
   kcoreaddons,
   lz4,
-  xxHash,
+  xxhash,
   ffmpeg_6,
   protobuf,
   openal-soft,
@@ -71,7 +71,7 @@ stdenv.mkDerivation (finalAttrs: {
     qtbase
     qtsvg
     lz4
-    xxHash
+    xxhash
     ffmpeg_6
     openal-soft
     minizip
diff --git a/pkgs/applications/networking/sync/rsync/default.nix b/pkgs/applications/networking/sync/rsync/default.nix
index 3e715826ae4c..2a540d19bf55 100644
--- a/pkgs/applications/networking/sync/rsync/default.nix
+++ b/pkgs/applications/networking/sync/rsync/default.nix
@@ -15,7 +15,7 @@
   enableOpenSSL ? true,
   openssl,
   enableXXHash ? true,
-  xxHash,
+  xxhash,
   enableZstd ? true,
   zstd,
   nixosTests,
@@ -55,7 +55,7 @@ stdenv.mkDerivation rec {
   ++ lib.optional enableZstd zstd
   ++ lib.optional enableLZ4 lz4
   ++ lib.optional enableOpenSSL openssl
-  ++ lib.optional enableXXHash xxHash;
+  ++ lib.optional enableXXHash xxhash;
 
   configureFlags = [
     (lib.enableFeature enableLZ4 "lz4")
diff --git a/pkgs/by-name/ap/apt/package.nix b/pkgs/by-name/ap/apt/package.nix
index 0a87132ccd60..2b418f3d03f4 100644
--- a/pkgs/by-name/ap/apt/package.nix
+++ b/pkgs/by-name/ap/apt/package.nix
@@ -25,7 +25,7 @@
   triehash,
   udev,
   w3m,
-  xxHash,
+  xxhash,
   xz,
   zstd,
   withDocs ? true,
@@ -83,7 +83,7 @@ stdenv.mkDerivation (finalAttrs: {
     lz4
     p11-kit
     udev
-    xxHash
+    xxhash
     xz
     zstd
   ]
diff --git a/pkgs/by-name/bo/borgbackup/package.nix b/pkgs/by-name/bo/borgbackup/package.nix
index c43c2a359888..7bd091fe7793 100644
--- a/pkgs/by-name/bo/borgbackup/package.nix
+++ b/pkgs/by-name/bo/borgbackup/package.nix
@@ -9,7 +9,7 @@
   openssh,
   openssl,
   python3,
-  xxHash,
+  xxhash,
   zstd,
   installShellFiles,
   nixosTests,
@@ -62,7 +62,7 @@ python.pkgs.buildPythonApplication (finalAttrs: {
   buildInputs = [
     libb2
     lz4
-    xxHash
+    xxhash
     zstd
     openssl
   ]
diff --git a/pkgs/by-name/cc/ccache/package.nix b/pkgs/by-name/cc/ccache/package.nix
index 1247c6069b10..d064e1616fd9 100644
--- a/pkgs/by-name/cc/ccache/package.nix
+++ b/pkgs/by-name/cc/ccache/package.nix
@@ -9,7 +9,7 @@
   perl,
   fmt,
   hiredis,
-  xxHash,
+  xxhash,
   zstd,
   bashInteractive,
   doctest,
@@ -76,7 +76,7 @@ stdenv.mkDerivation (finalAttrs: {
   buildInputs = [
     fmt
     hiredis
-    xxHash
+    xxhash
     zstd
   ];
 
diff --git a/pkgs/by-name/ch/chiaki-ng/package.nix b/pkgs/by-name/ch/chiaki-ng/package.nix
index ae7a059f31f6..8c7f0c722489 100644
--- a/pkgs/by-name/ch/chiaki-ng/package.nix
+++ b/pkgs/by-name/ch/chiaki-ng/package.nix
@@ -26,7 +26,7 @@
   shaderc,
   lcms2,
   libdovi,
-  xxHash,
+  xxhash,
   kdePackages,
 }:
 
@@ -87,7 +87,7 @@ stdenv.mkDerivation (finalAttrs: {
     shaderc
     lcms2
     libdovi
-    xxHash
+    xxhash
   ];
 
   env.NIX_CFLAGS_COMPILE = "-std=gnu17";
diff --git a/pkgs/by-name/da/daikhan/package.nix b/pkgs/by-name/da/daikhan/package.nix
index 9ce93bb6bac2..067c56fd3fdf 100644
--- a/pkgs/by-name/da/daikhan/package.nix
+++ b/pkgs/by-name/da/daikhan/package.nix
@@ -15,7 +15,7 @@
   libgee,
   gst_all_1,
   sqlite,
-  xxHash,
+  xxhash,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -51,7 +51,7 @@ stdenv.mkDerivation (finalAttrs: {
     gst_all_1.gst-plugins-ugly
     gst_all_1.gst-plugins-rs
     sqlite
-    xxHash
+    xxhash
   ];
 
   mesonFlags = [
diff --git a/pkgs/by-name/da/dav1d/package.nix b/pkgs/by-name/da/dav1d/package.nix
index 8645a513b61f..c0feda75a56f 100644
--- a/pkgs/by-name/da/dav1d/package.nix
+++ b/pkgs/by-name/da/dav1d/package.nix
@@ -6,7 +6,7 @@
   ninja,
   nasm,
   pkg-config,
-  xxHash,
+  xxhash,
   withTools ? false, # "dav1d" binary
   withExamples ? false,
   SDL2, # "dav1dplay" binary
@@ -49,7 +49,7 @@ stdenv.mkDerivation (finalAttrs: {
   ];
   # TODO: doxygen (currently only HTML and not build by default).
   buildInputs = [
-    xxHash
+    xxhash
   ]
   ++ lib.optional withExamples SDL2
   ++ lib.optionals useVulkan [
diff --git a/pkgs/by-name/de/debugedit/package.nix b/pkgs/by-name/de/debugedit/package.nix
index e2a7ee58f038..65c1516da2d1 100644
--- a/pkgs/by-name/de/debugedit/package.nix
+++ b/pkgs/by-name/de/debugedit/package.nix
@@ -7,7 +7,7 @@
   autoreconfHook,
   pkg-config,
   elfutils,
-  xxHash,
+  xxhash,
   help2man,
   util-linux,
   cpio,
@@ -41,7 +41,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   buildInputs = [
     elfutils
-    xxHash
+    xxhash
   ];
 
   nativeCheckInputs = [
diff --git a/pkgs/by-name/do/dolphin-emu/package.nix b/pkgs/by-name/do/dolphin-emu/package.nix
index b23dab82c6a7..34e4b4610955 100644
--- a/pkgs/by-name/do/dolphin-emu/package.nix
+++ b/pkgs/by-name/do/dolphin-emu/package.nix
@@ -33,7 +33,7 @@
   pugixml,
   sdl3,
   sfml,
-  xxHash,
+  xxhash,
   xz,
   zlib-ng,
   # linux-only
@@ -109,7 +109,7 @@ stdenv.mkDerivation (finalAttrs: {
     qt6.qtsvg
     sdl3
     sfml
-    xxHash
+    xxhash
     xz
     zlib-ng
   ]
diff --git a/pkgs/by-name/dr/dragonflydb/package.nix b/pkgs/by-name/dr/dragonflydb/package.nix
index 79eca3f54019..cbd5fe185d33 100644
--- a/pkgs/by-name/dr/dragonflydb/package.nix
+++ b/pkgs/by-name/dr/dragonflydb/package.nix
@@ -25,7 +25,7 @@
   re2,
   re-flex,
   uni-algo,
-  xxHash,
+  xxhash,
   zstd,
 
   # Build tools
@@ -151,7 +151,7 @@ stdenv.mkDerivation {
     cp -r --no-preserve=mode,ownership ${mimalloc224} build/deps-nixpkgs/mimalloc224
     cp -r --no-preserve=mode,ownership ${pugixml.src} build/deps-nixpkgs/pugixml
     cp -r --no-preserve=mode,ownership ${re-flex.src} build/deps-nixpkgs/reflex
-    cp -r --no-preserve=mode,ownership ${xxHash.src} build/deps-nixpkgs/xxhash
+    cp -r --no-preserve=mode,ownership ${xxhash.src} build/deps-nixpkgs/xxhash
     cp -r --no-preserve=mode,ownership ${zstd.src} build/deps-nixpkgs/zstd
 
     # c-ares is provided as a tarball, extract it
diff --git a/pkgs/by-name/du/duperemove/package.nix b/pkgs/by-name/du/duperemove/package.nix
index 88d12d8f043e..0fce7eb7f88a 100644
--- a/pkgs/by-name/du/duperemove/package.nix
+++ b/pkgs/by-name/du/duperemove/package.nix
@@ -4,7 +4,7 @@
   fetchFromGitHub,
   libbsd,
   libgcrypt,
-  xxHash,
+  xxhash,
   pkg-config,
   glib,
   linuxHeaders ? stdenv.cc.libc.linuxHeaders,
@@ -38,7 +38,7 @@ stdenv.mkDerivation (finalAttrs: {
     linuxHeaders
     sqlite
     util-linux
-    xxHash
+    xxhash
   ];
 
   makeFlags = [
diff --git a/pkgs/by-name/dw/dwarfs/package.nix b/pkgs/by-name/dw/dwarfs/package.nix
index 657b1f05b435..f28206e12998 100644
--- a/pkgs/by-name/dw/dwarfs/package.nix
+++ b/pkgs/by-name/dw/dwarfs/package.nix
@@ -22,7 +22,7 @@
   python3,
   range-v3,
   ronn,
-  xxHash,
+  xxhash,
   utf8cpp,
   zstd,
   parallel-hashmap,
@@ -78,7 +78,7 @@ stdenv.mkDerivation (finalAttrs: {
     jemalloc
     libarchive
     lz4
-    xxHash
+    xxhash
     utf8cpp
     zstd
 
diff --git a/pkgs/by-name/dw/dwz/package.nix b/pkgs/by-name/dw/dwz/package.nix
index da4cc9bb4e2a..9e7c88f55971 100644
--- a/pkgs/by-name/dw/dwz/package.nix
+++ b/pkgs/by-name/dw/dwz/package.nix
@@ -3,7 +3,7 @@
   stdenv,
   fetchurl,
   elfutils,
-  xxHash,
+  xxhash,
   dejagnu,
   gdb,
 }:
@@ -24,7 +24,7 @@ stdenv.mkDerivation (finalAttrs: {
   nativeBuildInputs = [ elfutils ];
 
   buildInputs = [
-    xxHash
+    xxhash
     elfutils
   ];
 
diff --git a/pkgs/by-name/er/erofs-utils/package.nix b/pkgs/by-name/er/erofs-utils/package.nix
index 3d8b5ebe8e90..817dd4068163 100644
--- a/pkgs/by-name/er/erofs-utils/package.nix
+++ b/pkgs/by-name/er/erofs-utils/package.nix
@@ -6,7 +6,7 @@
   pkg-config,
   fuse,
   util-linux,
-  xxHash,
+  xxhash,
   lz4,
   xz,
   zlib,
@@ -39,7 +39,7 @@ stdenv.mkDerivation (finalAttrs: {
   ];
   buildInputs = [
     util-linux
-    xxHash
+    xxhash
     lz4
     zlib
     xz
diff --git a/pkgs/by-name/fb/fbthrift/package.nix b/pkgs/by-name/fb/fbthrift/package.nix
index ad1870ec19ac..dc0a5d4aa157 100644
--- a/pkgs/by-name/fb/fbthrift/package.nix
+++ b/pkgs/by-name/fb/fbthrift/package.nix
@@ -16,7 +16,7 @@
   wangle,
   zlib,
   zstd,
-  xxHash,
+  xxhash,
 
   mvfst,
 
@@ -72,7 +72,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   propagatedBuildInputs = [
     mvfst
-    xxHash
+    xxhash
   ];
 
   cmakeFlags = [
diff --git a/pkgs/by-name/fe/fex/package.nix b/pkgs/by-name/fe/fex/package.nix
index 197e3a2671a3..d64b8232365a 100644
--- a/pkgs/by-name/fe/fex/package.nix
+++ b/pkgs/by-name/fe/fex/package.nix
@@ -7,7 +7,7 @@
   pkg-config,
   python3,
   nix-update-script,
-  xxHash,
+  xxhash,
   fmt,
   libxml2,
   openssl,
@@ -183,7 +183,7 @@ llvmPackages.stdenv.mkDerivation (finalAttrs: {
   ++ lib.optional withQt qt6.wrapQtAppsHook;
 
   buildInputs = [
-    xxHash
+    xxhash
     fmt
     libxml2
     openssl
diff --git a/pkgs/by-name/gd/gdb/package.nix b/pkgs/by-name/gd/gdb/package.nix
index f0fc625aff49..f6098601ad8d 100644
--- a/pkgs/by-name/gd/gdb/package.nix
+++ b/pkgs/by-name/gd/gdb/package.nix
@@ -21,7 +21,7 @@
   dejagnu,
   sourceHighlight,
   libiconv,
-  xxHash,
+  xxhash,
 
   withTui ? true,
   ncurses,
@@ -107,7 +107,7 @@ stdenv.mkDerivation (finalAttrs: {
     zstd
     xz
     sourceHighlight
-    xxHash
+    xxhash
     dejagnu # for tests
   ]
   ++ optional withTui ncurses
diff --git a/pkgs/by-name/gr/groonga/package.nix b/pkgs/by-name/gr/groonga/package.nix
index f1e43c9041bb..c6d882d4feee 100644
--- a/pkgs/by-name/gr/groonga/package.nix
+++ b/pkgs/by-name/gr/groonga/package.nix
@@ -9,7 +9,7 @@
   pkg-config,
   rapidjson,
   testers,
-  xxHash,
+  xxhash,
   zstd,
   postgresqlPackages,
   suggestSupport ? false,
@@ -42,7 +42,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   buildInputs = [
     rapidjson
-    xxHash
+    xxhash
     zstd
     mecab
     kytea
diff --git a/pkgs/by-name/ha/hashcat/package.nix b/pkgs/by-name/ha/hashcat/package.nix
index 31987ce3c8da..e905d0bd94af 100644
--- a/pkgs/by-name/ha/hashcat/package.nix
+++ b/pkgs/by-name/ha/hashcat/package.nix
@@ -14,7 +14,7 @@
   python3,
   rocmPackages ? { },
   rocmSupport ? config.rocmSupport,
-  xxHash,
+  xxhash,
   zlib,
   libiconv,
 }:
@@ -59,7 +59,7 @@ stdenv.mkDerivation (finalAttrs: {
         simplejson
       ]
     ))
-    xxHash
+    xxhash
     zlib
   ]
   ++ lib.optionals stdenv.hostPlatform.isDarwin [
diff --git a/pkgs/by-name/ka/kagen/package.nix b/pkgs/by-name/ka/kagen/package.nix
index f9593f948010..cafacbff8ac7 100644
--- a/pkgs/by-name/ka/kagen/package.nix
+++ b/pkgs/by-name/ka/kagen/package.nix
@@ -23,7 +23,7 @@ stdenv.mkDerivation (finalAttrs: {
     owner = "KarlsruheGraphGeneration";
     repo = "kagen";
     tag = "v${finalAttrs.version}";
-    # use vendor libmorton and xxHash
+    # use vendor libmorton and xxhash
     fetchSubmodules = true;
     hash = "sha256-VLQxeI9EzeJEp1krlLPRSct3SQmAF8cj34u3fkmppQg=";
   };
diff --git a/pkgs/by-name/ki/kitty/package.nix b/pkgs/by-name/ki/kitty/package.nix
index 6760f22d1633..0d340a404b98 100644
--- a/pkgs/by-name/ki/kitty/package.nix
+++ b/pkgs/by-name/ki/kitty/package.nix
@@ -20,7 +20,7 @@
   libxext,
   wayland-protocols,
   wayland,
-  xxHash,
+  xxhash,
   nerd-fonts,
   lcms2,
   librsync,
@@ -76,7 +76,7 @@ buildPythonApplication rec {
     librsync
     matplotlib
     openssl.dev
-    xxHash
+    xxhash
   ]
   ++ lib.optionals stdenv.hostPlatform.isDarwin [
     libpng
diff --git a/pkgs/by-name/li/libpg_query/package.nix b/pkgs/by-name/li/libpg_query/package.nix
index 94ac3a3d48b8..3f78829abccd 100644
--- a/pkgs/by-name/li/libpg_query/package.nix
+++ b/pkgs/by-name/li/libpg_query/package.nix
@@ -5,7 +5,7 @@
   which,
   squawk,
   protobufc,
-  xxHash,
+  xxhash,
 }:
 stdenv.mkDerivation (finalAttrs: {
   pname = "libpg_query";
@@ -35,7 +35,7 @@ stdenv.mkDerivation (finalAttrs: {
     cp -r protobuf $out/include/protobuf
     ln -s ${protobufc.dev}/include/protobuf-c $out/include/protobuf-c
     cp -r ${protobufc.dev}/include/protobuf-c/* $out/include
-    ln -s ${xxHash}/include $out/include/xxhash
+    ln -s ${xxhash}/include $out/include/xxhash
     install -Dm644 pg_query.h -t $out/include
 
     runHook postInstall
diff --git a/pkgs/by-name/li/libplacebo/package.nix b/pkgs/by-name/li/libplacebo/package.nix
index fb3fbdf3b7a2..4cc43e9c310f 100644
--- a/pkgs/by-name/li/libplacebo/package.nix
+++ b/pkgs/by-name/li/libplacebo/package.nix
@@ -15,7 +15,7 @@
   libx11,
   libunwind,
   libdovi,
-  xxHash,
+  xxhash,
   fast-float,
   vulkanSupport ? true,
 }:
@@ -55,7 +55,7 @@ stdenv.mkDerivation (finalAttrs: {
     libx11
     libunwind
     libdovi
-    xxHash
+    xxhash
     vulkan-headers
   ]
   ++ lib.optionals vulkanSupport [
diff --git a/pkgs/by-name/li/libyang/package.nix b/pkgs/by-name/li/libyang/package.nix
index 7e31c1aac735..85ef0f7499e1 100644
--- a/pkgs/by-name/li/libyang/package.nix
+++ b/pkgs/by-name/li/libyang/package.nix
@@ -9,7 +9,7 @@
 
   # dependencies
   pcre2,
-  xxHash,
+  xxhash,
 
   # update script
   gitUpdater,
@@ -37,7 +37,7 @@ stdenv.mkDerivation (finalAttrs: {
   ];
 
   buildInputs = [
-    xxHash
+    xxhash
   ];
 
   propagatedBuildInputs = [
diff --git a/pkgs/by-name/lm/lms/package.nix b/pkgs/by-name/lm/lms/package.nix
index 6320250049e2..bbd0c8e45af3 100644
--- a/pkgs/by-name/lm/lms/package.nix
+++ b/pkgs/by-name/lm/lms/package.nix
@@ -17,7 +17,7 @@
   libice,
   stb,
   openssl,
-  xxHash,
+  xxhash,
   pugixml,
 }:
 
@@ -51,7 +51,7 @@ stdenv.mkDerivation (finalAttrs: {
     libice
     stb
     openssl
-    xxHash
+    xxhash
     pugixml
   ];
 
diff --git a/pkgs/by-name/pg/pgroll/package.nix b/pkgs/by-name/pg/pgroll/package.nix
index 2aef876939cc..1166bef016b3 100644
--- a/pkgs/by-name/pg/pgroll/package.nix
+++ b/pkgs/by-name/pg/pgroll/package.nix
@@ -3,7 +3,7 @@
   fetchFromGitHub,
   lib,
   libpg_query,
-  xxHash,
+  xxhash,
   testers,
 }:
 
@@ -29,7 +29,7 @@ buildGoModule (finalAttrs: {
 
   buildInputs = [
     libpg_query
-    xxHash
+    xxhash
   ];
 
   ldflags = [
diff --git a/pkgs/by-name/pi/pijul/package.nix b/pkgs/by-name/pi/pijul/package.nix
index 9642d452aa42..3f46c1e2c890 100644
--- a/pkgs/by-name/pi/pijul/package.nix
+++ b/pkgs/by-name/pi/pijul/package.nix
@@ -7,7 +7,7 @@
   pkg-config,
   libsodium,
   openssl,
-  xxHash,
+  xxhash,
   gitImportSupport ? true,
   libgit2 ? null,
 }:
@@ -31,7 +31,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
   buildInputs = [
     openssl
     libsodium
-    xxHash
+    xxhash
   ]
   ++ (lib.optionals gitImportSupport [ libgit2 ]);
 
diff --git a/pkgs/by-name/ro/root/package.nix b/pkgs/by-name/ro/root/package.nix
index c110d1941458..944b8bed060a 100644
--- a/pkgs/by-name/ro/root/package.nix
+++ b/pkgs/by-name/ro/root/package.nix
@@ -38,7 +38,7 @@
   procps,
   python3,
   which,
-  xxHash,
+  xxhash,
   zlib,
   zstd,
   giflib,
@@ -110,7 +110,7 @@ stdenv.mkDerivation (finalAttrs: {
     python3
     onetbb
     xrootd
-    xxHash
+    xxhash
     xz
     zlib
     zstd
diff --git a/pkgs/by-name/rs/rspamd/package.nix b/pkgs/by-name/rs/rspamd/package.nix
index e002e13c9d62..6e998f2600ee 100644
--- a/pkgs/by-name/rs/rspamd/package.nix
+++ b/pkgs/by-name/rs/rspamd/package.nix
@@ -22,7 +22,7 @@
   lapack,
   lua,
   libsodium,
-  xxHash,
+  xxhash,
   zstd,
   libarchive,
   # Enabling blas support breaks bayes filter training from dovecot in nixos-mailserver tests
@@ -70,7 +70,7 @@ stdenv.mkDerivation (finalAttrs: {
     icu
     jemalloc
     libsodium
-    xxHash
+    xxhash
     zstd
     libarchive
   ]
diff --git a/pkgs/by-name/sh/shadps4/package.nix b/pkgs/by-name/sh/shadps4/package.nix
index 87b323bf5a9a..3ff4dd9e4d3e 100644
--- a/pkgs/by-name/sh/shadps4/package.nix
+++ b/pkgs/by-name/sh/shadps4/package.nix
@@ -48,7 +48,7 @@
   vulkan-loader,
   vulkan-memory-allocator,
   xbyak,
-  xxHash,
+  xxhash,
   zlib-ng,
   zydis,
   nix-update-script,
@@ -127,7 +127,7 @@ gcc14Stdenv.mkDerivation (finalAttrs: {
     vulkan-loader
     vulkan-memory-allocator
     xbyak
-    xxHash
+    xxhash
     zlib-ng
     zydis
   ];
diff --git a/pkgs/by-name/va/vapoursynth-bestsource/package.nix b/pkgs/by-name/va/vapoursynth-bestsource/package.nix
index ef90fb7153d4..bff856f32a55 100644
--- a/pkgs/by-name/va/vapoursynth-bestsource/package.nix
+++ b/pkgs/by-name/va/vapoursynth-bestsource/package.nix
@@ -7,7 +7,7 @@
   pkg-config,
   vapoursynth,
   ffmpeg,
-  xxHash,
+  xxhash,
   gitUpdater,
 }:
 
@@ -37,7 +37,7 @@ stdenv.mkDerivation (finalAttrs: {
   buildInputs = [
     vapoursynth
     (ffmpeg.override { withLcms2 = true; })
-    xxHash
+    xxhash
   ];
 
   postPatch = ''
diff --git a/pkgs/by-name/xe/xemu/package.nix b/pkgs/by-name/xe/xemu/package.nix
index 683db61bbf58..6c6e7f164b9b 100644
--- a/pkgs/by-name/xe/xemu/package.nix
+++ b/pkgs/by-name/xe/xemu/package.nix
@@ -30,7 +30,7 @@
   cacert,
   darwin,
   desktopToDarwinBundle,
-  xxHash,
+  xxhash,
   tomlplusplus,
 }:
 
@@ -93,7 +93,7 @@ stdenv.mkDerivation (finalAttrs: {
     openssl
     vulkan-headers
     vulkan-loader
-    xxHash
+    xxhash
     tomlplusplus
   ]
   ++ lib.optionals stdenv.hostPlatform.isLinux [
diff --git a/pkgs/by-name/xp/xpra/package.nix b/pkgs/by-name/xp/xpra/package.nix
index 07094de10ae1..2faaa600a575 100644
--- a/pkgs/by-name/xp/xpra/package.nix
+++ b/pkgs/by-name/xp/xpra/package.nix
@@ -55,7 +55,7 @@
   xorgproto,
   libxkbfile,
   xorg-server,
-  xxHash,
+  xxhash,
   clang,
   withHtml ? true,
   xpra-html5,
@@ -185,7 +185,7 @@ effectiveBuildPythonApplication rec {
     libavif
     openh264
     libyuv
-    xxHash
+    xxhash
     systemd
   ]
   ++ lib.optional withNvenc [
diff --git a/pkgs/by-name/xv/xva-img/package.nix b/pkgs/by-name/xv/xva-img/package.nix
index 3f5d910d722e..718c31ef0aa0 100644
--- a/pkgs/by-name/xv/xva-img/package.nix
+++ b/pkgs/by-name/xv/xva-img/package.nix
@@ -4,7 +4,7 @@
   cmake,
   fetchFromGitHub,
   openssl,
-  xxHash,
+  xxhash,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -22,7 +22,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   buildInputs = [
     openssl
-    xxHash
+    xxhash
   ];
 
   postPatch = ''
diff --git a/pkgs/by-name/xx/xxHash/package.nix b/pkgs/by-name/xx/xxhash/package.nix
similarity index 98%
rename from pkgs/by-name/xx/xxHash/package.nix
rename to pkgs/by-name/xx/xxhash/package.nix
index bb6ef12918a2..678e9d1c1864 100644
--- a/pkgs/by-name/xx/xxHash/package.nix
+++ b/pkgs/by-name/xx/xxhash/package.nix
@@ -6,7 +6,7 @@
 }:
 
 stdenv.mkDerivation (finalAttrs: {
-  pname = "xxHash";
+  pname = "xxhash";
   version = "0.8.3";
 
   src = fetchFromGitHub {
diff --git a/pkgs/by-name/zr/zrythm/package.nix b/pkgs/by-name/zr/zrythm/package.nix
index 815fd6f3c795..de89862ebedd 100644
--- a/pkgs/by-name/zr/zrythm/package.nix
+++ b/pkgs/by-name/zr/zrythm/package.nix
@@ -57,7 +57,7 @@
   wrapGAppsHook4,
   writeScript,
   xdg-utils,
-  xxHash,
+  xxhash,
   yyjson,
   zix,
   zstd,
@@ -152,7 +152,7 @@ stdenv.mkDerivation (finalAttrs: {
     soxr
     vamp-plugin-sdk
     xdg-utils
-    xxHash
+    xxhash
     yyjson
     zix
     zstd
diff --git a/pkgs/development/haskell-modules/hackage-packages.nix b/pkgs/development/haskell-modules/hackage-packages.nix
index 4f99fa1f35ad..b4526e962049 100644
--- a/pkgs/development/haskell-modules/hackage-packages.nix
+++ b/pkgs/development/haskell-modules/hackage-packages.nix
@@ -276280,7 +276280,7 @@ self: {
           vector-algorithms,
           wai,
           warp,
-          xxHash,
+          xxhash,
           yaml,
         }:
         mkDerivation {
@@ -276378,7 +276378,7 @@ self: {
             libfolly
             libunwind
             rocksdb
-            xxHash
+            xxhash
           ];
           libraryToolDepends = [
             alex
@@ -276522,7 +276522,7 @@ self: {
         libfolly = null;
         inherit (pkgs) libunwind;
         inherit (pkgs) rocksdb;
-        inherit (pkgs) xxHash;
+        inherit (pkgs) xxhash;
       };
 
   glfw-group = callPackage (
@@ -753491,7 +753491,7 @@ self: {
       tasty-bench,
       tasty-quickcheck,
       text,
-      xxHash,
+      xxhash,
     }:
     mkDerivation {
       pname = "xxhash-ffi";
@@ -753503,7 +753503,7 @@ self: {
         hashable
         text
       ];
-      libraryPkgconfigDepends = [ xxHash ];
+      libraryPkgconfigDepends = [ xxhash ];
       testHaskellDepends = [
         base
         bytestring
@@ -753523,7 +753523,7 @@ self: {
       description = "Bindings and high-level helpers for xxHash";
       license = lib.licensesSpdx."BSD-3-Clause";
     }
-  ) { inherit (pkgs) xxHash; };
+  ) { inherit (pkgs) xxhash; };
 
   xz = callPackage (
     {
diff --git a/pkgs/development/ocaml-modules/bytesrw/default.nix b/pkgs/development/ocaml-modules/bytesrw/default.nix
index daa87419488f..2b015aa2a132 100644
--- a/pkgs/development/ocaml-modules/bytesrw/default.nix
+++ b/pkgs/development/ocaml-modules/bytesrw/default.nix
@@ -3,7 +3,7 @@
   fetchzip,
   libblake3,
   libmd,
-  xxHash,
+  xxhash,
   zlib,
   zstd,
   buildTopkgPackage,
@@ -26,7 +26,7 @@ buildTopkgPackage rec {
   buildInputs = [
     libblake3
     libmd
-    xxHash
+    xxhash
     zlib
     zstd
   ];
diff --git a/pkgs/development/ocaml-modules/xxhash/default.nix b/pkgs/development/ocaml-modules/xxhash/default.nix
index 941d01208657..4d7834aa8a6e 100644
--- a/pkgs/development/ocaml-modules/xxhash/default.nix
+++ b/pkgs/development/ocaml-modules/xxhash/default.nix
@@ -2,7 +2,7 @@
   lib,
   fetchFromGitHub,
   buildDunePackage,
-  xxHash,
+  pkgs,
   ctypes,
   ctypes-foreign,
   dune-configurator,
@@ -33,7 +33,7 @@ buildDunePackage rec {
   propagatedBuildInputs = [
     ctypes
     ctypes-foreign
-    xxHash
+    pkgs.xxhash
   ];
 
   doCheck = true;
diff --git a/pkgs/development/tools/analysis/radare2/default.nix b/pkgs/development/tools/analysis/radare2/default.nix
index 2c02ec2648ce..a26642c453db 100644
--- a/pkgs/development/tools/analysis/radare2/default.nix
+++ b/pkgs/development/tools/analysis/radare2/default.nix
@@ -22,7 +22,7 @@
   readline,
   ruby,
   vte,
-  xxHash,
+  xxhash,
   zlib,
   useX11 ? false,
   rubyBindings ? false,
@@ -109,7 +109,7 @@ stdenv.mkDerivation (finalAttrs: {
     # radare2 exposes r_lib which depends on these libraries
     file # for its list of magic numbers (`libmagic`)
     libzip
-    xxHash
+    xxhash
   ];
 
   postUnpack = ''
diff --git a/pkgs/development/tools/analysis/rizin/default.nix b/pkgs/development/tools/analysis/rizin/default.nix
index fa20ebdc8961..40b564e4dd68 100644
--- a/pkgs/development/tools/analysis/rizin/default.nix
+++ b/pkgs/development/tools/analysis/rizin/default.nix
@@ -15,7 +15,7 @@
   libmspack,
   libzip,
   lz4,
-  xxHash,
+  xxhash,
   xz,
   meson,
   python3,
@@ -105,7 +105,7 @@ let
       openssl
       libmspack
       tree-sitter
-      xxHash
+      xxhash
       xz
       zstd
       binutils
diff --git a/pkgs/servers/sql/postgresql/ext/pgroonga.nix b/pkgs/servers/sql/postgresql/ext/pgroonga.nix
index a0adcd2f3bd0..8dcca959985a 100644
--- a/pkgs/servers/sql/postgresql/ext/pgroonga.nix
+++ b/pkgs/servers/sql/postgresql/ext/pgroonga.nix
@@ -6,7 +6,7 @@
   pkg-config,
   postgresql,
   postgresqlBuildExtension,
-  xxHash,
+  xxhash,
 }:
 
 postgresqlBuildExtension (finalAttrs: {
@@ -24,7 +24,7 @@ postgresqlBuildExtension (finalAttrs: {
   buildInputs = [
     msgpack-c
     groonga
-    xxHash
+    xxhash
   ];
 
   makeFlags = [
diff --git a/pkgs/tools/typesetting/tex/texlive/bin.nix b/pkgs/tools/typesetting/tex/texlive/bin.nix
index d25380cbee0f..201c69c9ed06 100644
--- a/pkgs/tools/typesetting/tex/texlive/bin.nix
+++ b/pkgs/tools/typesetting/tex/texlive/bin.nix
@@ -42,7 +42,7 @@
   clisp,
   biber,
   woff2,
-  xxHash,
+  xxhash,
   makeWrapper,
   useFixedHashes,
   asymptote,
@@ -601,7 +601,7 @@ rec {
       ttfautohint
       woff2
       potrace
-      xxHash
+      xxhash
       mupdf-headless
     ];
 
diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index 39c035122197..c92bc03c18dc 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -2418,6 +2418,7 @@ mapAliases {
   xtrap = throw "XTrap was a proposed X11 extension that hasn't been in Xorg since X11R6 in 1994, it is deprecated and archived upstream."; # added 2025-12-13
   xulrunner = throw "'xulrunner' has been renamed to/replaced by 'firefox-unwrapped'"; # Converted to throw 2025-10-27
   xxgdb = throw "'xxgdb' seems inactive and doesn't compile with glibc 2.42"; # Added 2025-09-28
+  xxHash = warnAlias "'xxHash' has been renamed to 'xxhash'" xxhash; # Added 2026-02-12
   yabar = throw "'yabar' has been removed as the upstream project was archived"; # Added 2025-06-10
   yabar-unstable = throw "'yabar' has been removed as the upstream project was archived"; # Added 2025-06-10
   yafaray-core = throw "'yafaray-core' has been renamed to/replaced by 'libyafaray'"; # Converted to throw 2025-10-27