diff --git a/nixos/modules/services/misc/bees.nix b/nixos/modules/services/misc/bees.nix
index b0ed2d5c2862..6b8cae84642f 100644
--- a/nixos/modules/services/misc/bees.nix
+++ b/nixos/modules/services/misc/bees.nix
@@ -57,7 +57,7 @@ let
     };
     options.extraOptions = mkOption {
       type = listOf str;
-      default = [];
+      default = [ ];
       description = ''
         Extra command-line options passed to the daemon. See upstream bees documentation.
       '';
@@ -67,7 +67,8 @@ let
     };
   };
 
-in {
+in
+{
 
   options.services.beesd = {
     filesystems = mkOption {
@@ -87,37 +88,42 @@ in {
     };
   };
   config = {
-    systemd.services = mapAttrs' (name: fs: nameValuePair "beesd@${name}" {
-      description = "Block-level BTRFS deduplication for %i";
-      after = [ "sysinit.target" ];
+    systemd.services = mapAttrs'
+      (name: fs: nameValuePair "beesd@${name}" {
+        description = "Block-level BTRFS deduplication for %i";
+        after = [ "sysinit.target" ];
 
-      serviceConfig = let
-        configOpts = [
-          fs.spec
-          "verbosity=${toString fs.verbosity}"
-          "idxSizeMB=${toString fs.hashTableSizeMB}"
-          "workDir=${fs.workDir}"
-        ];
-        configOptsStr = escapeShellArgs configOpts;
-      in {
-        # Values from https://github.com/Zygo/bees/blob/v0.6.1/scripts/beesd%40.service.in
-        ExecStart = "${pkgs.bees}/bin/bees-service-wrapper run ${configOptsStr} -- --no-timestamps ${escapeShellArgs fs.extraOptions}";
-        ExecStopPost = "${pkgs.bees}/bin/bees-service-wrapper cleanup ${configOptsStr}";
-        CPUAccounting = true;
-        CPUWeight = 12;
-        IOSchedulingClass = "idle";
-        IOSchedulingPriority = 7;
-        IOWeight = 10;
-        KillMode = "control-group";
-        KillSignal = "SIGTERM";
-        MemoryAccounting = true;
-        Nice = 19;
-        Restart = "on-abnormal";
-        StartupCPUWeight = 25;
-        StartupIOWeight = 25;
-        SyslogIdentifier = "bees"; # would otherwise be "bees-service-wrapper"
-      };
-      wantedBy = ["multi-user.target"];
-    }) cfg.filesystems;
+        serviceConfig =
+          let
+            configOpts = [
+              fs.spec
+              "verbosity=${toString fs.verbosity}"
+              "idxSizeMB=${toString fs.hashTableSizeMB}"
+              "workDir=${fs.workDir}"
+            ];
+            configOptsStr = escapeShellArgs configOpts;
+          in
+          {
+            # Values from https://github.com/Zygo/bees/blob/v0.6.5/scripts/beesd@.service.in
+            ExecStart = "${pkgs.bees}/bin/bees-service-wrapper run ${configOptsStr} -- --no-timestamps ${escapeShellArgs fs.extraOptions}";
+            ExecStopPost = "${pkgs.bees}/bin/bees-service-wrapper cleanup ${configOptsStr}";
+            CPUAccounting = true;
+            CPUSchedulingPolicy = "batch";
+            CPUWeight = 12;
+            IOSchedulingClass = "idle";
+            IOSchedulingPriority = 7;
+            IOWeight = 10;
+            KillMode = "control-group";
+            KillSignal = "SIGTERM";
+            MemoryAccounting = true;
+            Nice = 19;
+            Restart = "on-abnormal";
+            StartupCPUWeight = 25;
+            StartupIOWeight = 25;
+            SyslogIdentifier = "beesd"; # would otherwise be "bees-service-wrapper"
+          };
+        wantedBy = [ "multi-user.target" ];
+      })
+      cfg.filesystems;
   };
 }
diff --git a/pkgs/tools/filesystems/bees/default.nix b/pkgs/tools/filesystems/bees/default.nix
index 7ba27208fe88..c82ea23debd9 100644
--- a/pkgs/tools/filesystems/bees/default.nix
+++ b/pkgs/tools/filesystems/bees/default.nix
@@ -1,26 +1,35 @@
-{ lib, stdenv, runCommand, fetchFromGitHub, bash, btrfs-progs, coreutils
-, python3Packages, util-linux, nixosTests }:
+{ lib
+, stdenv
+, runCommand
+, fetchFromGitHub
+, bash
+, btrfs-progs
+, coreutils
+, python3Packages
+, util-linux
+, nixosTests
+}:
 
 let
 
   bees = stdenv.mkDerivation rec {
     pname = "bees";
-    version = "0.6.3";
+    version = "0.6.5";
 
     src = fetchFromGitHub {
       owner = "Zygo";
       repo = "bees";
       rev = "v${version}";
-      sha256 = "sha256-brEjr7lhmKDCIDeLq+XP+ZTxv1RvwoUlszMSEYygxv8=";
+      sha256 = "11ppbf23b8ngzfy02am0skxlybzmgsp6kna21jimb01x9pp1q7l7";
     };
 
     buildInputs = [
-      btrfs-progs               # for btrfs/ioctl.h
-      util-linux                 # for uuid.h
+      btrfs-progs # for btrfs/ioctl.h
+      util-linux # for uuid.h
     ];
 
     nativeBuildInputs = [
-      python3Packages.markdown   # documentation build
+      python3Packages.markdown # documentation build
     ];
 
     preBuild = ''
@@ -56,11 +65,12 @@ let
 
 in
 
-(runCommand "bees-service" {
-  inherit bash bees coreutils;
-  utillinux = util-linux; # needs to be a valid shell variable name
-  btrfsProgs = btrfs-progs; # needs to be a valid shell variable name
-} ''
+(runCommand "bees-service"
+  {
+    inherit bash bees coreutils;
+    utillinux = util-linux; # needs to be a valid shell variable name
+    btrfsProgs = btrfs-progs; # needs to be a valid shell variable name
+  } ''
   mkdir -p -- "$out/bin"
   substituteAll ${./bees-service-wrapper} "$out"/bin/bees-service-wrapper
   chmod +x "$out"/bin/bees-service-wrapper