diff --git a/default.nix b/default.nix
index f19ff107..ae012821 100644
--- a/default.nix
+++ b/default.nix
@@ -1,32 +1,144 @@
-{ nixpkgs ? (import ./nix/nixpkgs.nix)
-}:
+{ lib
+, filter
 
-with nixpkgs;
+, stdenv
+, pkg-config
+, attr
+, libuuid
+, libscrypt
+, libsodium
+, keyutils
 
-stdenv.mkDerivation rec {
-  name = "bcachefs-tools-${version}";
-  version = "git";
+, liburcu
+, zlib
+, libaio
+, udev
+, zstd
+, lz4
 
-  src = lib.cleanSource ./.; # NOTE: ignore .git, otherwise things get weird!
+, python39
+, python39Packages
+, docutils
+, nixosTests
 
-  nativeBuildInputs = [ git pkgconfig ];
-  buildInputs =
-    [ liburcu libuuid libaio zlib attr keyutils
-      libsodium libscrypt
-    ];
+, lastModified
+, versionString ? lastModified
 
-  enableParallelBuilding = true;
-  makeFlags =
-    [ "PREFIX=$(out)"
-    ];
+, inShell ? false
+, debugMode ? inShell
 
-  meta = with stdenv.lib; {
-    description = "Userspace tools for bcachefs";
-    homepage    = http://bcachefs.org;
-    license     = licenses.gpl2;
-    platforms   = platforms.linux;
-    maintainers =
-      [ "Kent Overstreet <kent.overstreet@gmail.com>"
-      ];
-  };
+, testWithValgrind ? true
+, valgrind 
+
+, fuseSupport ? false
+, fuse3 ? null }:
+
+assert fuseSupport -> fuse3 != null;
+assert testWithValgrind -> valgrind != null;
+stdenv.mkDerivation {
+	pname = "bcachefs-tools";
+
+	version = "v0.1-flake-${versionString}";
+	VERSION = "v0.1-flake-${versionString}";
+	
+	src = filter.filter {
+		name = "bcachefs-tools";
+		root = ./.;
+		exclude = [
+			./rust-src
+			
+			./.git
+			./nix
+			
+			./flake.nix
+			./flake.lock
+		];
+	};
+
+	postPatch = "patchShebangs --build doc/macro2rst.py";
+
+	nativeBuildInputs = [
+		# used to find dependencies
+		## see ./INSTALL
+		pkg-config
+	];
+	buildInputs = [
+		# bcachefs explicit dependencies
+		## see ./INSTALL
+		libaio
+		
+		# libblkid
+		keyutils # libkeyutils
+		lz4 # liblz4
+		
+		libscrypt
+		libsodium
+		liburcu
+		libuuid
+		zstd # libzstd
+		zlib # zlib1g
+		valgrind
+
+		# unspecified dependencies
+		attr
+		udev
+
+		# documentation depenedencies
+		docutils
+		python39Packages.pygments
+	] ++ (lib.optional fuseSupport fuse3)
+	++ (lib.optional testWithValgrind valgrind) ;
+
+	makeFlags = [
+		"PREFIX=${placeholder "out"}"
+	] ++ lib.optional debugMode "EXTRA_CFLAGS=-ggdb";
+
+	installFlags = [
+		"INITRAMFS_DIR=${placeholder "out"}/etc/initramfs-tools"
+	];
+
+	doCheck = true; # needs bcachefs module loaded on builder
+
+	checkInputs = [
+		python39Packages.pytest
+		python39Packages.pytest-xdist
+	] ++ lib.optional testWithValgrind valgrind;
+	
+	checkFlags = [ 
+		"BCACHEFS_TEST_USE_VALGRIND=${if testWithValgrind then "yes" else "no"}"
+		# cannot escape spaces within make flags, quotes are stripped
+		"PYTEST=pytest" # "PYTEST_ARGS='-n4 --version'"
+	];
+
+	preCheck =
+		''
+			makeFlagsArray+=(PYTEST_ARGS="--verbose -n4")
+		'' +
+		lib.optionalString fuseSupport ''
+			rm tests/test_fuse.py
+		'';
+
+	dontStrip = debugMode == true;
+	passthru = {
+		bcachefs_revision = let 
+			file = builtins.readFile ./.bcachefs_revision;
+			removeLineFeeds = str: lib.lists.foldr (lib.strings.removeSuffix) str ["\r" "\n"];
+		in removeLineFeeds file;
+		
+		tests = {
+			smoke-test = nixosTests.bcachefs;
+		};
+	};
+
+	enableParallelBuilding = true;
+	meta = with lib; {
+		description = "Userspace tools for bcachefs";
+		homepage    = http://bcachefs.org;
+		license     = licenses.gpl2;
+		platforms   = platforms.linux;
+		maintainers =
+			[ "Kent Overstreet <kent.overstreet@gmail.com>"
+			];
+
+	};
 }