diff --git a/pkgs/os-specific/bsd/freebsd/default.nix b/pkgs/os-specific/bsd/freebsd/default.nix
index 398b2ff6fa6d..965185cc14aa 100644
--- a/pkgs/os-specific/bsd/freebsd/default.nix
+++ b/pkgs/os-specific/bsd/freebsd/default.nix
@@ -1,10 +1,7 @@
 { stdenv, lib, stdenvNoCC
 , makeScopeWithSplicing', generateSplicesForMkScope
 , buildPackages
-, bsdSetupHook, makeSetupHook
-, fetchgit, fetchzip, coreutils, groff, mandoc, byacc, flex, which, m4, gawk, substituteAll, runtimeShell
-, zlib, expat, libmd
-, runCommand, writeShellScript, writeText, symlinkJoin
+, fetchgit, fetchzip
 }:
 
 let
@@ -20,885 +17,66 @@ let
     sha256 = "14nhk0kls83xfb64d5xy14vpi6k8laswjycjg80indq9pkcr2rlv";
   };
 
-  freebsdSetupHook = makeSetupHook {
-    name = "freebsd-setup-hook";
-  } ./setup-hook.sh;
-
-  mkBsdArch = stdenv':  {
-    x86_64 = "amd64";
-    aarch64 = "arm64";
-    i486 = "i386";
-    i586 = "i386";
-    i686 = "i386";
-  }.${stdenv'.hostPlatform.parsed.cpu.name}
-    or stdenv'.hostPlatform.parsed.cpu.name;
-
-  install-wrapper = ''
-    set -eu
-
-    args=()
-    declare -i path_args=0
-
-    while (( $# )); do
-      if (( $# == 1 )); then
-        if (( path_args > 1)) || [[ "$1" = */ ]]; then
-          mkdir -p "$1"
-        else
-          mkdir -p "$(dirname "$1")"
-        fi
-      fi
-      case $1 in
-        -C) ;;
-        -o | -g) shift ;;
-        -s) ;;
-        -m | -l)
-          # handle next arg so not counted as path arg
-          args+=("$1" "$2")
-          shift
-          ;;
-        -*) args+=("$1") ;;
-        *)
-          path_args+=1
-          args+=("$1")
-          ;;
-      esac
-      shift
-    done
-  '';
-
 in makeScopeWithSplicing' {
   otherSplices = generateSplicesForMkScope "freebsd";
-  f = (self: let
-    inherit (self) mkDerivation;
-  in {
-  inherit freebsdSrc;
+  f = (self: lib.packagesFromDirectoryRecursive {
+    callPackage = self.callPackage;
+    directory = ./pkgs;
+  } // {
+    inherit freebsdSrc;
 
-  ports = fetchzip {
-    url = "https://cgit.freebsd.org/ports/snapshot/ports-dde3b2b456c3a4bdd217d0bf3684231cc3724a0a.tar.gz";
-    sha256 = "BpHqJfnGOeTE7tkFJBx0Wk8ryalmf4KNTit/Coh026E=";
-  };
-
-  # Why do we have splicing and yet do `nativeBuildInputs = with self; ...`?
-  # See note in ../netbsd/default.nix.
-
-  compatIfNeeded = lib.optional (!stdenvNoCC.hostPlatform.isFreeBSD) self.compat;
-
-  mkDerivation = lib.makeOverridable (attrs: let
-    stdenv' = if attrs.noCC or false then stdenvNoCC else stdenv;
-  in stdenv'.mkDerivation (rec {
-    pname = "${attrs.pname or (baseNameOf attrs.path)}-freebsd";
-    inherit version;
-    src = runCommand "${pname}-filtered-src" {
-      nativeBuildInputs = [ rsync ];
-    } ''
-      for p in ${lib.concatStringsSep " " ([ attrs.path ] ++ attrs.extraPaths or [])}; do
-        set -x
-        path="$out/$p"
-        mkdir -p "$(dirname "$path")"
-        src_path="${freebsdSrc}/$p"
-        if [[ -d "$src_path" ]]; then src_path+=/; fi
-        rsync --chmod="+w" -r "$src_path" "$path"
-        set +x
-      done
-    '';
-
-    extraPaths = [ ];
-
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal
-      install tsort lorder mandoc groff #statHook
-    ];
-    buildInputs = with self; compatIfNeeded;
-
-    HOST_SH = stdenv'.shell;
-
-    # Since STRIP below is the flag
-    STRIPBIN = "${stdenv.cc.bintools.targetPrefix}strip";
-
-    makeFlags = [
-      "STRIP=-s" # flag to install, not command
-    ] ++ lib.optional (!stdenv.hostPlatform.isFreeBSD) "MK_WERROR=no";
-
-    # amd64 not x86_64 for this on unlike NetBSD
-    MACHINE_ARCH = mkBsdArch stdenv';
-
-    MACHINE = mkBsdArch stdenv';
-
-    MACHINE_CPUARCH = MACHINE_ARCH;
-
-    COMPONENT_PATH = attrs.path or null;
-
-    strictDeps = true;
-
-    meta = with lib; {
-      maintainers = with maintainers; [ ericson2314 ];
-      platforms = platforms.unix;
-      license = licenses.bsd2;
+    ports = fetchzip {
+      url = "https://cgit.freebsd.org/ports/snapshot/ports-dde3b2b456c3a4bdd217d0bf3684231cc3724a0a.tar.gz";
+      sha256 = "BpHqJfnGOeTE7tkFJBx0Wk8ryalmf4KNTit/Coh026E=";
     };
-  } // lib.optionalAttrs stdenv'.hasCC {
-    # TODO should CC wrapper set this?
-    CPP = "${stdenv'.cc.targetPrefix}cpp";
-  } // lib.optionalAttrs stdenv'.isDarwin {
-    MKRELRO = "no";
-  } // lib.optionalAttrs (stdenv'.cc.isClang or false) {
-    HAVE_LLVM = lib.versions.major (lib.getVersion stdenv'.cc.cc);
-  } // lib.optionalAttrs (stdenv'.cc.isGNU or false) {
-    HAVE_GCC = lib.versions.major (lib.getVersion stdenv'.cc.cc);
-  } // lib.optionalAttrs (stdenv'.isx86_32) {
-    USE_SSP = "no";
-  } // lib.optionalAttrs (attrs.headersOnly or false) {
-    installPhase = "includesPhase";
-    dontBuild = true;
-  } // attrs));
 
-  ##
-  ## START BOOTSTRAPPING
-  ##
-  makeMinimal = mkDerivation rec {
-    inherit (self.make) path;
+    # Why do we have splicing and yet do `nativeBuildInputs = with self; ...`?
+    # See note in ../netbsd/default.nix.
 
-    buildInputs = with self; [];
-    nativeBuildInputs = with buildPackages.netbsd; [ bsdSetupHook freebsdSetupHook ];
+    compatIfNeeded = lib.optional (!stdenvNoCC.hostPlatform.isFreeBSD) self.compat;
 
-    skipIncludesPhase = true;
+    freebsd-lib = import ./lib { inherit version; };
 
-    makeFlags = [];
+    # Overridden arguments avoid cross package-set splicing issues,
+    # otherwise would just use implicit
+    # `lib.packagesFromDirectoryRecursive` auto-call.
 
-    postPatch = ''
-      patchShebangs configure
-      ${self.make.postPatch}
-    '';
+    compat = self.callPackage ./pkgs/compat/package.nix {
+      inherit stdenv;
+      inherit (buildPackages.freebsd) makeMinimal boot-install;
+    };
 
-    buildPhase = ''
-      runHook preBuild
+    csu = self.callPackage ./pkgs/csu.nix {
+      inherit (buildPackages.freebsd) makeMinimal install gencat;
+      inherit (self) include;
+    };
 
-      sh ./make-bootstrap.sh
+    include = self.callPackage ./pkgs/include/package.nix {
+      inherit (buildPackages.freebsd) makeMinimal install rpcgen;
+    };
 
-      runHook postBuild
-    '';
+    install = self.callPackage ./pkgs/install.nix {
+      inherit (buildPackages.freebsd) makeMinimal;
+      inherit (self) mtree libnetbsd;
+    };
 
-    installPhase = ''
-      runHook preInstall
+    libc = self.callPackage ./pkgs/libc/package.nix {
+      inherit (buildPackages.freebsd) makeMinimal install gencat rpcgen;
+      inherit (self) csu include;
+    };
 
-      install -D bmake "$out/bin/bmake"
-      ln -s "$out/bin/bmake" "$out/bin/make"
-      mkdir -p "$out/share"
-      cp -r "$BSDSRCDIR/share/mk" "$out/share/mk"
-      find "$out/share/mk" -type f -print0 |
-        while IFS= read -r -d "" f; do
-          substituteInPlace "$f" --replace 'usr/' ""
-        done
-      substituteInPlace "$out/share/mk/bsd.symver.mk" \
-        --replace '/share/mk' "$out/share/mk"
+    libnetbsd = self.callPackage ./pkgs/libnetbsd/package.nix {
+      inherit (buildPackages.freebsd) makeMinimal;
+    };
 
-      runHook postInstall
-    '';
+    mkDerivation = self.callPackage ./pkgs/mkDerivation.nix {
+      inherit stdenv;
+      inherit (buildPackages.freebsd) makeMinimal install tsort;
+    };
 
-    postInstall = lib.optionalString (!stdenv.targetPlatform.isFreeBSD) ''
-      boot_mk="$BSDSRCDIR/tools/build/mk"
-      cp "$boot_mk"/Makefile.boot* "$out/share/mk"
-      replaced_mk="$out/share/mk.orig"
-      mkdir "$replaced_mk"
-      mv "$out"/share/mk/bsd.{lib,prog}.mk "$replaced_mk"
-      for m in bsd.{lib,prog}.mk; do
-        cp "$boot_mk/$m" "$out/share/mk"
-        substituteInPlace "$out/share/mk/$m" --replace '../../../share/mk' '../mk.orig'
-      done
-    '';
+    makeMinimal = self.callPackage ./pkgs/makeMinimal.nix {
+      inherit (self) make;
+    };
 
-    extraPaths = with self; make.extraPaths;
-  };
-
-  # Wrap NetBSD's install
-  boot-install = buildPackages.writeShellScriptBin "boot-install" (install-wrapper + ''
-
-    ${buildPackages.netbsd.install}/bin/xinstall "''${args[@]}"
-  '');
-
-  compat = mkDerivation rec {
-    pname = "compat";
-    path = "tools/build";
-    extraPaths = [
-      "lib/libc/db"
-      "lib/libc/stdlib" # getopt
-      "lib/libc/gen" # getcap
-      "lib/libc/locale" # rpmatch
-    ] ++ lib.optionals stdenv.hostPlatform.isLinux [
-      "lib/libc/string" # strlcpy
-      "lib/libutil"
-    ] ++ [
-      "contrib/libc-pwcache"
-      "contrib/libc-vis"
-      "sys/libkern"
-      "sys/kern/subr_capability.c"
-
-      # Take only individual headers, or else we will clobber native libc, etc.
-
-      "sys/rpc/types.h"
-
-      # Listed in Makekfile as INC
-      "include/mpool.h"
-      "include/ndbm.h"
-      "include/err.h"
-      "include/stringlist.h"
-      "include/a.out.h"
-      "include/nlist.h"
-      "include/db.h"
-      "include/getopt.h"
-      "include/nl_types.h"
-      "include/elf.h"
-      "sys/sys/ctf.h"
-
-      # Listed in Makekfile as SYSINC
-
-      "sys/sys/capsicum.h"
-      "sys/sys/caprights.h"
-      "sys/sys/imgact_aout.h"
-      "sys/sys/nlist_aout.h"
-      "sys/sys/nv.h"
-      "sys/sys/dnv.h"
-      "sys/sys/cnv.h"
-
-      "sys/sys/elf32.h"
-      "sys/sys/elf64.h"
-      "sys/sys/elf_common.h"
-      "sys/sys/elf_generic.h"
-      "sys/${mkBsdArch stdenv}/include"
-    ] ++ lib.optionals stdenv.hostPlatform.isx86 [
-      "sys/x86/include"
-    ] ++ [
-
-      "sys/sys/queue.h"
-      "sys/sys/md5.h"
-      "sys/sys/sbuf.h"
-      "sys/sys/tree.h"
-      "sys/sys/font.h"
-      "sys/sys/consio.h"
-      "sys/sys/fnv_hash.h"
-
-      "sys/crypto/chacha20/_chacha.h"
-      "sys/crypto/chacha20/chacha.h"
-      # included too, despite ".c"
-      "sys/crypto/chacha20/chacha.c"
-
-      "sys/fs"
-      "sys/ufs"
-      "sys/sys/disk"
-
-      "lib/libcapsicum"
-      "lib/libcasper"
-    ];
-
-    patches = [
-      ./compat-install-dirs.patch
-      ./compat-fix-typedefs-locations.patch
-    ];
-
-    preBuild = ''
-      NIX_CFLAGS_COMPILE+=' -I../../include -I../../sys'
-
-      cp ../../sys/${mkBsdArch stdenv}/include/elf.h ../../sys/sys
-      cp ../../sys/${mkBsdArch stdenv}/include/elf.h ../../sys/sys/${mkBsdArch stdenv}
-    '' + lib.optionalString stdenv.hostPlatform.isx86 ''
-      cp ../../sys/x86/include/elf.h ../../sys/x86
-    '';
-
-    setupHooks = [
-      ../../../build-support/setup-hooks/role.bash
-      ./compat-setup-hook.sh
-    ];
-
-    # This one has an ifdefed `#include_next` that makes it annoying.
-    postInstall = ''
-      rm ''${!outputDev}/0-include/libelf.h
-    '';
-
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal
-      boot-install
-
-      which
-    ];
-    buildInputs = [ expat zlib ];
-
-    makeFlags = [
-      "STRIP=-s" # flag to install, not command
-      "MK_WERROR=no"
-      "HOST_INCLUDE_ROOT=${lib.getDev stdenv.cc.libc}/include"
-      "INSTALL=boot-install"
-    ];
-
-    preIncludes = ''
-      mkdir -p $out/{0,1}-include
-      cp --no-preserve=mode -r cross-build/include/common/* $out/0-include
-    '' + lib.optionalString stdenv.hostPlatform.isLinux ''
-      cp --no-preserve=mode -r cross-build/include/linux/* $out/1-include
-    '' + lib.optionalString stdenv.hostPlatform.isDarwin ''
-      cp --no-preserve=mode -r cross-build/include/darwin/* $out/1-include
-    '';
-  };
-
-  libnetbsd = mkDerivation {
-    path = "lib/libnetbsd";
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal mandoc groff
-      (if stdenv.hostPlatform == stdenv.buildPlatform
-       then boot-install
-       else install)
-    ];
-    patches = lib.optionals (!stdenv.hostPlatform.isFreeBSD) [
-      ./libnetbsd-do-install.patch
-      #./libnetbsd-define-__va_list.patch
-    ];
-    makeFlags = [
-      "STRIP=-s" # flag to install, not command
-      "MK_WERROR=no"
-    ] ++ lib.optional (stdenv.hostPlatform == stdenv.buildPlatform) "INSTALL=boot-install";
-    buildInputs = with self; compatIfNeeded;
-  };
-
-  # HACK: to ensure parent directories exist. This emulates GNU
-  # install’s -D option. No alternative seems to exist in BSD install.
-  install = let binstall = writeShellScript "binstall" (install-wrapper + ''
-
-    @out@/bin/xinstall "''${args[@]}"
-  ''); in mkDerivation {
-    path = "usr.bin/xinstall";
-    extraPaths = with self; [ mtree.path ];
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal mandoc groff
-      (if stdenv.hostPlatform == stdenv.buildPlatform
-       then boot-install
-       else install)
-    ];
-    skipIncludesPhase = true;
-    buildInputs = with self; compatIfNeeded ++ [ libmd libnetbsd ];
-    makeFlags = [
-      "STRIP=-s" # flag to install, not command
-      "MK_WERROR=no"
-      "TESTSDIR=${builtins.placeholder "test"}"
-    ] ++ lib.optional (stdenv.hostPlatform == stdenv.buildPlatform) "INSTALL=boot-install";
-    postInstall = ''
-      install -D -m 0550 ${binstall} $out/bin/binstall
-      substituteInPlace $out/bin/binstall --subst-var out
-      mv $out/bin/install $out/bin/xinstall
-      ln -s ./binstall $out/bin/install
-    '';
-    outputs = [ "out" "man" "test" ];
-  };
-
-  sed = mkDerivation {
-    path = "usr.bin/sed";
-    TESTSRC = "${freebsdSrc}/contrib/netbsd-tests";
-    MK_TESTS = "no";
-  };
-
-  # Don't add this to nativeBuildInputs directly.  Use statHook instead.
-  stat = mkDerivation {
-    path = "usr.bin/stat";
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-    ];
-  };
-
-  # stat isn't in POSIX, and NetBSD stat supports a completely
-  # different range of flags than GNU stat, so including it in PATH
-  # breaks stdenv.  Work around that with a hook that will point
-  # NetBSD's build system and NetBSD stat without including it in
-  # PATH.
-  statHook = makeSetupHook {
-    name = "netbsd-stat-hook";
-  } (writeText "netbsd-stat-hook-impl" ''
-    makeFlagsArray+=(TOOL_STAT=${self.stat}/bin/stat)
-  '');
-
-  tsort = mkDerivation {
-    path = "usr.bin/tsort";
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-    ];
-  };
-
-  lorder = mkDerivation rec {
-    path = "usr.bin/lorder";
-    noCC = true;
-    dontBuild = true;
-    installPhase = ''
-      mkdir -p "$out/bin" "$man/share/man"
-      mv "lorder.sh" "$out/bin/lorder"
-      chmod +x "$out/bin/lorder"
-      mv "lorder.1" "$man/share/man"
-    '';
-    nativeBuildInputs = [ bsdSetupHook freebsdSetupHook ];
-    buildInputs = [];
-    outputs = [ "out" "man" ];
-  };
-
-  ##
-  ## END BOOTSTRAPPING
-  ##
-
-  ##
-  ## START COMMAND LINE TOOLS
-  ##
-  make = mkDerivation {
-    path = "contrib/bmake";
-    version = "9.2";
-    postPatch = ''
-      # make needs this to pick up our sys make files
-      export NIX_CFLAGS_COMPILE+=" -D_PATH_DEFSYSPATH=\"$out/share/mk\""
-
-    '' + lib.optionalString stdenv.isDarwin ''
-      substituteInPlace $BSDSRCDIR/share/mk/bsd.sys.mk \
-        --replace '-Wl,--fatal-warnings' "" \
-        --replace '-Wl,--warn-shared-textrel' ""
-    '';
-    postInstall = ''
-      make -C $BSDSRCDIR/share/mk FILESDIR=$out/share/mk install
-    '';
-    extraPaths = [ "share/mk" ]
-      ++ lib.optional (!stdenv.hostPlatform.isFreeBSD) "tools/build/mk";
-  };
-  mtree = mkDerivation {
-    path = "contrib/mtree";
-    extraPaths = with self; [ mknod.path ];
-  };
-
-  mknod = mkDerivation {
-    path = "sbin/mknod";
-  };
-
-  rpcgen = mkDerivation rec {
-    path = "usr.bin/rpcgen";
-    patches = lib.optionals (stdenv.hostPlatform.libc == "glibc") [
-      # `WUNTRACED` is defined privately `bits/waitflags.h` in glibc.
-      # But instead of having a regular header guard, it has some silly
-      # non-modular logic. `stdlib.h` will include it if `sys/wait.h`
-      # hasn't yet been included (for it would first), and vice versa.
-      #
-      # The problem is that with the FreeBSD compat headers, one of
-      # those headers ends up included other headers...which ends up
-      # including the other one, this means by the first time we reach
-      # `#include `<bits/waitflags.h>`, both `_SYS_WAIT_H` and
-      # `_STDLIB_H` are already defined! Thus, we never ned up including
-      # `<bits/waitflags.h>` and defining `WUNTRACED`.
-      #
-      # This hacks around this by manually including `WUNTRACED` until
-      # the problem is fixed properly in glibc.
-      ./rpcgen-glibc-hack.patch
-    ];
-  };
-
-  gencat = mkDerivation {
-    path = "usr.bin/gencat";
-  };
-
-  file2c = mkDerivation {
-    path = "usr.bin/file2c";
-    MK_TESTS = "no";
-  };
-
-  libnv = mkDerivation {
-    path = "lib/libnv";
-    extraPaths = [
-      "sys/contrib/libnv"
-      "sys/sys"
-    ];
-    MK_TESTS = "no";
-  };
-
-  libsbuf = mkDerivation {
-    path = "lib/libsbuf";
-    extraPaths = [
-      "sys/kern"
-    ];
-    MK_TESTS = "no";
-  };
-
-  libelf = mkDerivation {
-    path = "lib/libelf";
-    extraPaths = [
-      "contrib/elftoolchain/libelf"
-      "contrib/elftoolchain/common"
-      "sys/sys/elf32.h"
-      "sys/sys/elf64.h"
-      "sys/sys/elf_common.h"
-    ];
-    BOOTSTRAPPING = !stdenv.isFreeBSD;
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-
-      m4
-    ];
-    MK_TESTS = "no";
-  };
-
-  libdwarf = mkDerivation {
-    path = "lib/libdwarf";
-    extraPaths = [
-      "contrib/elftoolchain/libdwarf"
-      "contrib/elftoolchain/common"
-      "sys/sys/elf32.h"
-      "sys/sys/elf64.h"
-      "sys/sys/elf_common.h"
-    ];
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-
-      m4
-    ];
-    buildInputs = with self; compatIfNeeded ++ [
-      libelf
-    ];
-    MK_TESTS = "no";
-  };
-
-  uudecode = mkDerivation {
-    path = "usr.bin/uudecode";
-    MK_TESTS = "no";
-  };
-
-  config = mkDerivation {
-    path = "usr.sbin/config";
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-
-      flex byacc file2c
-    ];
-    buildInputs = with self; compatIfNeeded ++ [ libnv libsbuf ];
-  };
-  ##
-  ## END COMMAND LINE TOOLS
-  ##
-
-  ##
-  ## START HEADERS
-  ##
-  include = mkDerivation {
-    path = "include";
-
-    extraPaths = [
-      "contrib/libc-vis"
-      "etc/mtree/BSD.include.dist"
-      "sys"
-    ];
-
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal
-      install
-      mandoc groff rsync /*nbperf*/ rpcgen
-
-      # HACK use NetBSD's for now
-      buildPackages.netbsd.mtree
-    ];
-
-    patches = [
-      ./no-perms-BSD.include.dist.patch
-    ];
-
-    # The makefiles define INCSDIR per subdirectory, so we have to set
-    # something else on the command line so those definitions aren't
-    # overridden.
-    postPatch = ''
-      find "$BSDSRCDIR" -name Makefile -exec \
-        sed -i -E \
-          -e 's_/usr/include_''${INCSDIR0}_' \
-          {} \;
-    '';
-
-    makeFlags = [
-      "RPCGEN_CPP=${buildPackages.stdenv.cc.cc}/bin/cpp"
-    ];
-
-    # multiple header dirs, see above
-    postConfigure = ''
-      makeFlags=''${makeFlags/INCSDIR/INCSDIR0}
-    '';
-
-    headersOnly = true;
-
-    MK_HESIOD = "yes";
-
-    meta.platforms = lib.platforms.freebsd;
-  };
-
-  ##
-  ## END HEADERS
-  ##
-
-  csu = mkDerivation {
-    path = "lib/csu";
-    extraPaths = with self; [
-      "lib/Makefile.inc"
-      "lib/libc/include/libc_private.h"
-    ];
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal
-      install
-
-      flex byacc gencat
-    ];
-    buildInputs = with self; [ include ];
-    MK_TESTS = "no";
-    meta.platforms = lib.platforms.freebsd;
-  };
-
-  libc = mkDerivation rec {
-    pname = "libc";
-    path = "lib/libc";
-    extraPaths = [
-      "etc/group"
-      "etc/master.passwd"
-      "etc/shells"
-      "lib/libmd"
-      "lib/libutil"
-      "lib/msun"
-      "sys/kern"
-      "sys/libkern"
-      "sys/sys"
-      "sys/crypto/chacha20"
-      "include/rpcsvc"
-      "contrib/jemalloc"
-      "contrib/gdtoa"
-      "contrib/libc-pwcache"
-      "contrib/libc-vis"
-      "contrib/tzcode/stdtime"
-
-      # libthr
-      "lib/libthr"
-      "lib/libthread_db"
-      "libexec/rtld-elf"
-
-      # librpcsvc
-      "lib/librpcsvc"
-
-      # librt
-      "lib/librt"
-
-      # libcrypt
-      "lib/libcrypt"
-      "lib/libmd"
-      "sys/crypto/sha2"
-    ];
-
-    patches = [
-      # Hack around broken propogating MAKEFLAGS to submake, just inline logic
-      ./libc-msun-arch-subdir.patch
-
-      # Don't force -lcompiler-rt, we don't actually call it that
-      ./libc-no-force--lcompiler-rt.patch
-
-      # Fix extra include dir to get rpcsvc headers.
-      ./librpcsvc-include-subdir.patch
-    ];
-
-    postPatch = ''
-      substituteInPlace $COMPONENT_PATH/Makefile --replace '.include <src.opts.mk>' ""
-    '';
-
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal
-      install
-
-      flex byacc gencat rpcgen
-    ];
-    buildInputs = with self; [ include csu ];
-    env.NIX_CFLAGS_COMPILE = "-B${self.csu}/lib";
-
-    # Suppress lld >= 16 undefined version errors
-    # https://github.com/freebsd/freebsd-src/commit/2ba84b4bcdd6012e8cfbf8a0d060a4438623a638
-    env.NIX_LDFLAGS = lib.optionalString (stdenv.targetPlatform.linker == "lld") "--undefined-version";
-
-    makeFlags = [
-      "STRIP=-s" # flag to install, not command
-      # lib/libc/gen/getgrent.c has sketchy cast from `void *` to enum
-      "MK_WERROR=no"
-    ];
-
-    MK_SYMVER = "yes";
-    MK_SSP = "yes";
-    MK_NLS = "yes";
-    MK_ICONV = "no"; # TODO make srctop
-    MK_NS_CACHING = "yes";
-    MK_INET6_SUPPORT = "yes";
-    MK_HESIOD = "yes";
-    MK_NIS = "yes";
-    MK_HYPERV = "yes";
-    MK_FP_LIBC = "yes";
-
-    MK_TCSH = "no";
-    MK_MALLOC_PRODUCTION = "yes";
-
-    MK_TESTS = "no";
-
-    postInstall = ''
-      pushd ${self.include}
-      find . -type d -exec mkdir -p $out/\{} \;
-      find . \( -type f -o -type l \) -exec cp -pr \{} $out/\{} \;
-      popd
-
-      pushd ${self.csu}
-      find . -type d -exec mkdir -p $out/\{} \;
-      find . \( -type f -o -type l \) -exec cp -pr \{} $out/\{} \;
-      popd
-
-      sed -i -e 's| [^ ]*/libc_nonshared.a||' $out/lib/libc.so
-
-      $CC -nodefaultlibs -lgcc -shared -o $out/lib/libgcc_s.so
-
-      NIX_CFLAGS_COMPILE+=" -B$out/lib"
-      NIX_CFLAGS_COMPILE+=" -I$out/include"
-      NIX_LDFLAGS+=" -L$out/lib"
-
-      make -C $BSDSRCDIR/lib/libthr $makeFlags
-      make -C $BSDSRCDIR/lib/libthr $makeFlags install
-
-      make -C $BSDSRCDIR/lib/msun $makeFlags
-      make -C $BSDSRCDIR/lib/msun $makeFlags install
-
-      make -C $BSDSRCDIR/lib/librpcsvc $makeFlags
-      make -C $BSDSRCDIR/lib/librpcsvc $makeFlags install
-
-      make -C $BSDSRCDIR/lib/libutil $makeFlags
-      make -C $BSDSRCDIR/lib/libutil $makeFlags install
-
-      make -C $BSDSRCDIR/lib/librt $makeFlags
-      make -C $BSDSRCDIR/lib/librt $makeFlags install
-
-      make -C $BSDSRCDIR/lib/libcrypt $makeFlags
-      make -C $BSDSRCDIR/lib/libcrypt $makeFlags install
-    '';
-
-    meta.platforms = lib.platforms.freebsd;
-  };
-
-  ##
-  ## Kernel
-  ##
-
-  libspl = mkDerivation {
-    path = "cddl/lib/libspl";
-    extraPaths = [
-      "sys/contrib/openzfs/lib/libspl"
-      "sys/contrib/openzfs/include"
-
-      "cddl/compat/opensolaris/include"
-      "sys/contrib/openzfs/module/icp/include"
-      "sys/modules/zfs"
-    ];
-    # nativeBuildInputs = with buildPackages.freebsd; [
-    #   bsdSetupHook freebsdSetupHook
-    #   makeMinimal install mandoc groff
-
-    #   flex byacc file2c
-    # ];
-    # buildInputs = with self; compatIfNeeded ++ [ libnv libsbuf ];
-    meta.license = lib.licenses.cddl;
-  };
-
-  ctfconvert = mkDerivation {
-    path = "cddl/usr.bin/ctfconvert";
-    extraPaths = [
-      "cddl/compat/opensolaris"
-      "cddl/contrib/opensolaris"
-      "sys/cddl/compat/opensolaris"
-      "sys/cddl/contrib/opensolaris"
-      "sys/contrib/openzfs"
-    ];
-    OPENSOLARIS_USR_DISTDIR = "$(SRCTOP)/cddl/contrib/opensolaris";
-    OPENSOLARIS_SYS_DISTDIR = "$(SRCTOP)/sys/cddl/contrib/opensolaris";
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-
-      # flex byacc file2c
-    ];
-    buildInputs = with self; compatIfNeeded ++ [
-      libelf libdwarf zlib libspl
-    ];
-    meta.license = lib.licenses.cddl;
-  };
-
-  xargs-j = substituteAll {
-    name = "xargs-j";
-    shell = runtimeShell;
-    src = ../xargs-j.sh;
-    dir = "bin";
-    isExecutable = true;
-  };
-
-  sys = mkDerivation (let
-    cfg = "MINIMAL";
-  in rec {
-    path = "sys";
-
-    nativeBuildInputs = with buildPackages.freebsd; [
-      bsdSetupHook freebsdSetupHook
-      makeMinimal install mandoc groff
-
-      config rpcgen file2c gawk uudecode xargs-j
-      #ctfconvert
-    ];
-
-    patches = [
-      ./sys-gnu-date.patch
-      ./sys-no-explicit-intrinsics-dep.patch
-    ];
-
-    # --dynamic-linker /red/herring is used when building the kernel.
-    NIX_ENFORCE_PURITY = 0;
-
-    AWK = "${buildPackages.gawk}/bin/awk";
-
-    CWARNEXTRA = "-Wno-error=shift-negative-value -Wno-address-of-packed-member";
-
-    MK_CTF = "no";
-
-    KODIR = "${builtins.placeholder "out"}/kernel";
-    KMODDIR = "${builtins.placeholder "out"}/kernel";
-    DTBDIR = "${builtins.placeholder"out"}/dbt";
-
-    KERN_DEBUGDIR = "${builtins.placeholder "out"}/debug";
-    KERN_DEBUGDIR_KODIR = "${KERN_DEBUGDIR}/kernel";
-    KERN_DEBUGDIR_KMODDIR = "${KERN_DEBUGDIR}/kernel";
-
-    skipIncludesPhase = true;
-
-    configurePhase = ''
-      runHook preConfigure
-
-      for f in conf/kmod.mk contrib/dev/acpica/acpica_prep.sh; do
-        substituteInPlace "$f" --replace 'xargs -J' 'xargs-j '
-      done
-
-      for f in conf/*.mk; do
-        substituteInPlace "$f" --replace 'KERN_DEBUGDIR}''${' 'KERN_DEBUGDIR_'
-      done
-
-      cd ${mkBsdArch stdenv}/conf
-      sed -i ${cfg} \
-        -e 's/WITH_CTF=1/WITH_CTF=0/' \
-        -e '/KDTRACE/d'
-      config ${cfg}
-
-      runHook postConfigure
-    '';
-    preBuild = ''
-      cd ../compile/${cfg}
-    '';
   });
-
-});
 }
diff --git a/pkgs/os-specific/bsd/freebsd/lib/default.nix b/pkgs/os-specific/bsd/freebsd/lib/default.nix
new file mode 100644
index 000000000000..30fea7e17dce
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/lib/default.nix
@@ -0,0 +1,16 @@
+{ version }:
+
+{
+  inherit version;
+
+  mkBsdArch = stdenv':  {
+    x86_64 = "amd64";
+    aarch64 = "arm64";
+    i486 = "i386";
+    i586 = "i386";
+    i686 = "i386";
+  }.${stdenv'.hostPlatform.parsed.cpu.name}
+    or stdenv'.hostPlatform.parsed.cpu.name;
+
+  install-wrapper = builtins.readFile ./install-wrapper.sh;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/lib/install-wrapper.sh b/pkgs/os-specific/bsd/freebsd/lib/install-wrapper.sh
new file mode 100644
index 000000000000..91a7a2679f20
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/lib/install-wrapper.sh
@@ -0,0 +1,30 @@
+set -eu
+
+args=()
+declare -i path_args=0
+
+while (( $# )); do
+  if (( $# == 1 )); then
+    if (( path_args > 1)) || [[ "$1" = */ ]]; then
+      mkdir -p "$1"
+    else
+      mkdir -p "$(dirname "$1")"
+    fi
+  fi
+  case $1 in
+    -C) ;;
+    -o | -g) shift ;;
+    -s) ;;
+    -m | -l)
+      # handle next arg so not counted as path arg
+      args+=("$1" "$2")
+      shift
+      ;;
+    -*) args+=("$1") ;;
+    *)
+      path_args+=1
+      args+=("$1")
+      ;;
+  esac
+  shift
+done
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/boot-install.nix b/pkgs/os-specific/bsd/freebsd/pkgs/boot-install.nix
new file mode 100644
index 000000000000..71ecef1bcae4
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/boot-install.nix
@@ -0,0 +1,7 @@
+{ buildPackages, freebsd-lib }:
+
+# Wrap NetBSD's install
+buildPackages.writeShellScriptBin "boot-install" (freebsd-lib.install-wrapper + ''
+
+  ${buildPackages.netbsd.install}/bin/xinstall "''${args[@]}"
+'')
diff --git a/pkgs/os-specific/bsd/freebsd/compat-fix-typedefs-locations.patch b/pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-fix-typedefs-locations.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/compat-fix-typedefs-locations.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-fix-typedefs-locations.patch
diff --git a/pkgs/os-specific/bsd/freebsd/compat-install-dirs.patch b/pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-install-dirs.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/compat-install-dirs.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-install-dirs.patch
diff --git a/pkgs/os-specific/bsd/freebsd/compat-setup-hook.sh b/pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-setup-hook.sh
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/compat-setup-hook.sh
rename to pkgs/os-specific/bsd/freebsd/pkgs/compat/compat-setup-hook.sh
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/compat/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/compat/package.nix
new file mode 100644
index 000000000000..5e4528fbf46a
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/compat/package.nix
@@ -0,0 +1,135 @@
+{ lib, stdenv, mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, boot-install
+, which
+, freebsd-lib
+, expat, zlib,
+}:
+
+let
+  inherit (freebsd-lib) mkBsdArch;
+in
+
+mkDerivation rec {
+  pname = "compat";
+  path = "tools/build";
+  extraPaths = [
+    "lib/libc/db"
+    "lib/libc/stdlib" # getopt
+    "lib/libc/gen" # getcap
+    "lib/libc/locale" # rpmatch
+  ] ++ lib.optionals stdenv.hostPlatform.isLinux [
+    "lib/libc/string" # strlcpy
+    "lib/libutil"
+  ] ++ [
+    "contrib/libc-pwcache"
+    "contrib/libc-vis"
+    "sys/libkern"
+    "sys/kern/subr_capability.c"
+
+    # Take only individual headers, or else we will clobber native libc, etc.
+
+    "sys/rpc/types.h"
+
+    # Listed in Makekfile as INC
+    "include/mpool.h"
+    "include/ndbm.h"
+    "include/err.h"
+    "include/stringlist.h"
+    "include/a.out.h"
+    "include/nlist.h"
+    "include/db.h"
+    "include/getopt.h"
+    "include/nl_types.h"
+    "include/elf.h"
+    "sys/sys/ctf.h"
+
+    # Listed in Makekfile as SYSINC
+
+    "sys/sys/capsicum.h"
+    "sys/sys/caprights.h"
+    "sys/sys/imgact_aout.h"
+    "sys/sys/nlist_aout.h"
+    "sys/sys/nv.h"
+    "sys/sys/dnv.h"
+    "sys/sys/cnv.h"
+
+    "sys/sys/elf32.h"
+    "sys/sys/elf64.h"
+    "sys/sys/elf_common.h"
+    "sys/sys/elf_generic.h"
+    "sys/${mkBsdArch stdenv}/include"
+  ] ++ lib.optionals stdenv.hostPlatform.isx86 [
+    "sys/x86/include"
+  ] ++ [
+
+    "sys/sys/queue.h"
+    "sys/sys/md5.h"
+    "sys/sys/sbuf.h"
+    "sys/sys/tree.h"
+    "sys/sys/font.h"
+    "sys/sys/consio.h"
+    "sys/sys/fnv_hash.h"
+
+    "sys/crypto/chacha20/_chacha.h"
+    "sys/crypto/chacha20/chacha.h"
+    # included too, despite ".c"
+    "sys/crypto/chacha20/chacha.c"
+
+    "sys/fs"
+    "sys/ufs"
+    "sys/sys/disk"
+
+    "lib/libcapsicum"
+    "lib/libcasper"
+  ];
+
+  patches = [
+    ./compat-install-dirs.patch
+    ./compat-fix-typedefs-locations.patch
+  ];
+
+  preBuild = ''
+    NIX_CFLAGS_COMPILE+=' -I../../include -I../../sys'
+
+    cp ../../sys/${mkBsdArch stdenv}/include/elf.h ../../sys/sys
+    cp ../../sys/${mkBsdArch stdenv}/include/elf.h ../../sys/sys/${mkBsdArch stdenv}
+  '' + lib.optionalString stdenv.hostPlatform.isx86 ''
+    cp ../../sys/x86/include/elf.h ../../sys/x86
+  '';
+
+  setupHooks = [
+    ../../../../../build-support/setup-hooks/role.bash
+    ./compat-setup-hook.sh
+  ];
+
+  # This one has an ifdefed `#include_next` that makes it annoying.
+  postInstall = ''
+    rm ''${!outputDev}/0-include/libelf.h
+  '';
+
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal
+    boot-install
+
+    which
+  ];
+  buildInputs = [ expat zlib ];
+
+  makeFlags = [
+    "STRIP=-s" # flag to install, not command
+    "MK_WERROR=no"
+    "HOST_INCLUDE_ROOT=${lib.getDev stdenv.cc.libc}/include"
+    "INSTALL=boot-install"
+  ];
+
+  preIncludes = ''
+    mkdir -p $out/{0,1}-include
+    cp --no-preserve=mode -r cross-build/include/common/* $out/0-include
+  '' + lib.optionalString stdenv.hostPlatform.isLinux ''
+    cp --no-preserve=mode -r cross-build/include/linux/* $out/1-include
+  '' + lib.optionalString stdenv.hostPlatform.isDarwin ''
+    cp --no-preserve=mode -r cross-build/include/darwin/* $out/1-include
+  '';
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/config.nix b/pkgs/os-specific/bsd/freebsd/pkgs/config.nix
new file mode 100644
index 000000000000..641cfc46b4e9
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/config.nix
@@ -0,0 +1,17 @@
+{ mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+, flex, byacc, file2c
+, compatIfNeeded, libnv, libsbuf
+}:
+
+mkDerivation {
+  path = "usr.sbin/config";
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+
+    flex byacc file2c
+  ];
+  buildInputs = compatIfNeeded ++ [ libnv libsbuf ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/csu.nix b/pkgs/os-specific/bsd/freebsd/pkgs/csu.nix
new file mode 100644
index 000000000000..0b17cb1c8481
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/csu.nix
@@ -0,0 +1,25 @@
+{ lib, mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal
+, install
+, flex, byacc, gencat
+, include
+}:
+
+mkDerivation {
+  path = "lib/csu";
+  extraPaths = [
+    "lib/Makefile.inc"
+    "lib/libc/include/libc_private.h"
+  ];
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal
+    install
+
+    flex byacc gencat
+  ];
+  buildInputs = [ include ];
+  MK_TESTS = "no";
+  meta.platforms = lib.platforms.freebsd;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/ctfconvert.nix b/pkgs/os-specific/bsd/freebsd/pkgs/ctfconvert.nix
new file mode 100644
index 000000000000..0aebc9b3d0b9
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/ctfconvert.nix
@@ -0,0 +1,28 @@
+{ lib, stdenv, mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+, compatIfNeeded, libelf, libdwarf, zlib, libspl
+}:
+
+mkDerivation {
+  path = "cddl/usr.bin/ctfconvert";
+  extraPaths = [
+    "cddl/compat/opensolaris"
+    "cddl/contrib/opensolaris"
+    "sys/cddl/compat/opensolaris"
+    "sys/cddl/contrib/opensolaris"
+    "sys/contrib/openzfs"
+  ];
+  OPENSOLARIS_USR_DISTDIR = "$(SRCTOP)/cddl/contrib/opensolaris";
+  OPENSOLARIS_SYS_DISTDIR = "$(SRCTOP)/sys/cddl/contrib/opensolaris";
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+
+    # flex byacc file2c
+  ];
+  buildInputs = compatIfNeeded ++ [
+    libelf libdwarf zlib libspl
+  ];
+  meta.license = lib.licenses.cddl;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/file2c.nix b/pkgs/os-specific/bsd/freebsd/pkgs/file2c.nix
new file mode 100644
index 000000000000..ff35d97afe36
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/file2c.nix
@@ -0,0 +1,6 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "usr.bin/file2c";
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/package.nix
new file mode 100644
index 000000000000..430c4c5c43ac
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/package.nix
@@ -0,0 +1,5 @@
+{ makeSetupHook }:
+
+makeSetupHook {
+  name = "freebsd-setup-hook";
+} ./setup-hook.sh
diff --git a/pkgs/os-specific/bsd/freebsd/setup-hook.sh b/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/setup-hook.sh
rename to pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/gencat.nix b/pkgs/os-specific/bsd/freebsd/pkgs/gencat.nix
new file mode 100644
index 000000000000..e9ae9f27cc05
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/gencat.nix
@@ -0,0 +1,5 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "usr.bin/gencat";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/no-perms-BSD.include.dist.patch b/pkgs/os-specific/bsd/freebsd/pkgs/include/no-perms-BSD.include.dist.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/no-perms-BSD.include.dist.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/include/no-perms-BSD.include.dist.patch
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/include/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/include/package.nix
new file mode 100644
index 000000000000..73fa887c5123
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/include/package.nix
@@ -0,0 +1,56 @@
+{ lib, mkDerivation
+, buildPackages
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal
+, install
+, mandoc, groff, rsync /*, nbperf*/, rpcgen
+}:
+
+mkDerivation {
+  path = "include";
+
+  extraPaths = [
+    "contrib/libc-vis"
+    "etc/mtree/BSD.include.dist"
+    "sys"
+  ];
+
+  nativeBuildInputs =  [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal
+    install
+    mandoc groff rsync /*nbperf*/ rpcgen
+
+    # HACK use NetBSD's for now
+    buildPackages.netbsd.mtree
+  ];
+
+  patches = [
+    ./no-perms-BSD.include.dist.patch
+  ];
+
+  # The makefiles define INCSDIR per subdirectory, so we have to set
+  # something else on the command line so those definitions aren't
+  # overridden.
+  postPatch = ''
+    find "$BSDSRCDIR" -name Makefile -exec \
+      sed -i -E \
+        -e 's_/usr/include_''${INCSDIR0}_' \
+        {} \;
+  '';
+
+  makeFlags = [
+    "RPCGEN_CPP=${buildPackages.stdenv.cc.cc}/bin/cpp"
+  ];
+
+  # multiple header dirs, see above
+  postConfigure = ''
+    makeFlags=''${makeFlags/INCSDIR/INCSDIR0}
+  '';
+
+  headersOnly = true;
+
+  MK_HESIOD = "yes";
+
+  meta.platforms = lib.platforms.freebsd;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/install.nix b/pkgs/os-specific/bsd/freebsd/pkgs/install.nix
new file mode 100644
index 000000000000..3db6cd3633d4
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/install.nix
@@ -0,0 +1,41 @@
+{ lib, stdenv, mkDerivation, writeShellScript
+, freebsd-lib
+, mtree
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, mandoc, groff
+, boot-install, install
+, compatIfNeeded, libmd, libnetbsd
+}:
+
+# HACK: to ensure parent directories exist. This emulates GNU
+# install’s -D option. No alternative seems to exist in BSD install.
+let
+  binstall = writeShellScript "binstall" (freebsd-lib.install-wrapper + ''
+
+    @out@/bin/xinstall "''${args[@]}"
+  '');
+in mkDerivation {
+  path = "usr.bin/xinstall";
+  extraPaths = [ mtree.path ];
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal mandoc groff
+    (if stdenv.hostPlatform == stdenv.buildPlatform
+     then boot-install
+     else install)
+  ];
+  skipIncludesPhase = true;
+  buildInputs = compatIfNeeded ++ [ libmd libnetbsd ];
+  makeFlags = [
+    "STRIP=-s" # flag to install, not command
+    "MK_WERROR=no"
+    "TESTSDIR=${builtins.placeholder "test"}"
+  ] ++ lib.optional (stdenv.hostPlatform == stdenv.buildPlatform) "INSTALL=boot-install";
+  postInstall = ''
+    install -D -m 0550 ${binstall} $out/bin/binstall
+    substituteInPlace $out/bin/binstall --subst-var out
+    mv $out/bin/install $out/bin/xinstall
+    ln -s ./binstall $out/bin/install
+  '';
+  outputs = [ "out" "man" "test" ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/libc-msun-arch-subdir.patch b/pkgs/os-specific/bsd/freebsd/pkgs/libc/libc-msun-arch-subdir.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/libc-msun-arch-subdir.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/libc/libc-msun-arch-subdir.patch
diff --git a/pkgs/os-specific/bsd/freebsd/libc-no-force--lcompiler-rt.patch b/pkgs/os-specific/bsd/freebsd/pkgs/libc/libc-no-force--lcompiler-rt.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/libc-no-force--lcompiler-rt.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/libc/libc-no-force--lcompiler-rt.patch
diff --git a/pkgs/os-specific/bsd/freebsd/librpcsvc-include-subdir.patch b/pkgs/os-specific/bsd/freebsd/pkgs/libc/librpcsvc-include-subdir.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/librpcsvc-include-subdir.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/libc/librpcsvc-include-subdir.patch
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libc/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libc/package.nix
new file mode 100644
index 000000000000..0225d44be4c3
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libc/package.nix
@@ -0,0 +1,139 @@
+{ lib, stdenv, mkDerivation
+
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal
+, install
+, flex, byacc, gencat, rpcgen
+
+, csu, include
+}:
+
+mkDerivation rec {
+  pname = "libc";
+  path = "lib/libc";
+  extraPaths = [
+    "etc/group"
+    "etc/master.passwd"
+    "etc/shells"
+    "lib/libmd"
+    "lib/libutil"
+    "lib/msun"
+    "sys/kern"
+    "sys/libkern"
+    "sys/sys"
+    "sys/crypto/chacha20"
+    "include/rpcsvc"
+    "contrib/jemalloc"
+    "contrib/gdtoa"
+    "contrib/libc-pwcache"
+    "contrib/libc-vis"
+    "contrib/tzcode/stdtime"
+
+    # libthr
+    "lib/libthr"
+    "lib/libthread_db"
+    "libexec/rtld-elf"
+
+    # librpcsvc
+    "lib/librpcsvc"
+
+    # librt
+    "lib/librt"
+
+    # libcrypt
+    "lib/libcrypt"
+    "lib/libmd"
+    "sys/crypto/sha2"
+  ];
+
+  patches = [
+    # Hack around broken propogating MAKEFLAGS to submake, just inline logic
+    ./libc-msun-arch-subdir.patch
+
+    # Don't force -lcompiler-rt, we don't actually call it that
+    ./libc-no-force--lcompiler-rt.patch
+
+    # Fix extra include dir to get rpcsvc headers.
+    ./librpcsvc-include-subdir.patch
+  ];
+
+  postPatch = ''
+    substituteInPlace $COMPONENT_PATH/Makefile --replace '.include <src.opts.mk>' ""
+  '';
+
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal
+    install
+
+    flex byacc gencat rpcgen
+  ];
+  buildInputs = [ include csu ];
+  env.NIX_CFLAGS_COMPILE = "-B${csu}/lib";
+
+  # Suppress lld >= 16 undefined version errors
+  # https://github.com/freebsd/freebsd-src/commit/2ba84b4bcdd6012e8cfbf8a0d060a4438623a638
+  env.NIX_LDFLAGS = lib.optionalString (stdenv.targetPlatform.linker == "lld") "--undefined-version";
+
+  makeFlags = [
+    "STRIP=-s" # flag to install, not command
+    # lib/libc/gen/getgrent.c has sketchy cast from `void *` to enum
+    "MK_WERROR=no"
+  ];
+
+  MK_SYMVER = "yes";
+  MK_SSP = "yes";
+  MK_NLS = "yes";
+  MK_ICONV = "no"; # TODO make srctop
+  MK_NS_CACHING = "yes";
+  MK_INET6_SUPPORT = "yes";
+  MK_HESIOD = "yes";
+  MK_NIS = "yes";
+  MK_HYPERV = "yes";
+  MK_FP_LIBC = "yes";
+
+  MK_TCSH = "no";
+  MK_MALLOC_PRODUCTION = "yes";
+
+  MK_TESTS = "no";
+
+  postInstall = ''
+    pushd ${include}
+    find . -type d -exec mkdir -p $out/\{} \;
+    find . \( -type f -o -type l \) -exec cp -pr \{} $out/\{} \;
+    popd
+
+    pushd ${csu}
+    find . -type d -exec mkdir -p $out/\{} \;
+    find . \( -type f -o -type l \) -exec cp -pr \{} $out/\{} \;
+    popd
+
+    sed -i -e 's| [^ ]*/libc_nonshared.a||' $out/lib/libc.so
+
+    $CC -nodefaultlibs -lgcc -shared -o $out/lib/libgcc_s.so
+
+    NIX_CFLAGS_COMPILE+=" -B$out/lib"
+    NIX_CFLAGS_COMPILE+=" -I$out/include"
+    NIX_LDFLAGS+=" -L$out/lib"
+
+    make -C $BSDSRCDIR/lib/libthr $makeFlags
+    make -C $BSDSRCDIR/lib/libthr $makeFlags install
+
+    make -C $BSDSRCDIR/lib/msun $makeFlags
+    make -C $BSDSRCDIR/lib/msun $makeFlags install
+
+    make -C $BSDSRCDIR/lib/librpcsvc $makeFlags
+    make -C $BSDSRCDIR/lib/librpcsvc $makeFlags install
+
+    make -C $BSDSRCDIR/lib/libutil $makeFlags
+    make -C $BSDSRCDIR/lib/libutil $makeFlags install
+
+    make -C $BSDSRCDIR/lib/librt $makeFlags
+    make -C $BSDSRCDIR/lib/librt $makeFlags install
+
+    make -C $BSDSRCDIR/lib/libcrypt $makeFlags
+    make -C $BSDSRCDIR/lib/libcrypt $makeFlags install
+  '';
+
+  meta.platforms = lib.platforms.freebsd;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libdwarf.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libdwarf.nix
new file mode 100644
index 000000000000..9fc8fc5f9a62
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libdwarf.nix
@@ -0,0 +1,27 @@
+{ lib, stdenv, mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+, m4
+, compatIfNeeded, libelf
+}:
+
+mkDerivation {
+  path = "lib/libdwarf";
+  extraPaths = [
+    "contrib/elftoolchain/libdwarf"
+    "contrib/elftoolchain/common"
+    "sys/sys/elf32.h"
+    "sys/sys/elf64.h"
+    "sys/sys/elf_common.h"
+  ];
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+
+    m4
+  ];
+  buildInputs = compatIfNeeded ++ [
+    libelf
+  ];
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libelf.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libelf.nix
new file mode 100644
index 000000000000..a44ce1685e57
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libelf.nix
@@ -0,0 +1,24 @@
+{ lib, stdenv, mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+, m4
+}:
+
+mkDerivation {
+  path = "lib/libelf";
+  extraPaths = [
+    "contrib/elftoolchain/libelf"
+    "contrib/elftoolchain/common"
+    "sys/sys/elf32.h"
+    "sys/sys/elf64.h"
+    "sys/sys/elf_common.h"
+  ];
+  BOOTSTRAPPING = !stdenv.isFreeBSD;
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+
+    m4
+  ];
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/libnetbsd-do-install.patch b/pkgs/os-specific/bsd/freebsd/pkgs/libnetbsd/libnetbsd-do-install.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/libnetbsd-do-install.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/libnetbsd/libnetbsd-do-install.patch
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libnetbsd/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libnetbsd/package.nix
new file mode 100644
index 000000000000..4011e4d8a649
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libnetbsd/package.nix
@@ -0,0 +1,26 @@
+{ lib, stdenv
+, mkDerivation
+, bsdSetupHook, freebsdSetupHook, makeMinimal, mandoc, groff
+, boot-install, install
+, compatIfNeeded
+}:
+
+mkDerivation {
+  path = "lib/libnetbsd";
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal mandoc groff
+    (if stdenv.hostPlatform == stdenv.buildPlatform
+     then boot-install
+     else install)
+  ];
+  patches = lib.optionals (!stdenv.hostPlatform.isFreeBSD) [
+    ./libnetbsd-do-install.patch
+    #./libnetbsd-define-__va_list.patch
+  ];
+  makeFlags = [
+    "STRIP=-s" # flag to install, not command
+    "MK_WERROR=no"
+  ] ++ lib.optional (stdenv.hostPlatform == stdenv.buildPlatform) "INSTALL=boot-install";
+  buildInputs = compatIfNeeded;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libnv.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libnv.nix
new file mode 100644
index 000000000000..6ce61e5a68c7
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libnv.nix
@@ -0,0 +1,10 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "lib/libnv";
+  extraPaths = [
+    "sys/contrib/libnv"
+    "sys/sys"
+  ];
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libsbuf.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libsbuf.nix
new file mode 100644
index 000000000000..719474dbb11a
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libsbuf.nix
@@ -0,0 +1,9 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "lib/libsbuf";
+  extraPaths = [
+    "sys/kern"
+  ];
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libspl.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libspl.nix
new file mode 100644
index 000000000000..da5445a09fcd
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libspl.nix
@@ -0,0 +1,21 @@
+{ lib, mkDerivation }:
+
+mkDerivation {
+  path = "cddl/lib/libspl";
+  extraPaths = [
+    "sys/contrib/openzfs/lib/libspl"
+    "sys/contrib/openzfs/include"
+
+    "cddl/compat/opensolaris/include"
+    "sys/contrib/openzfs/module/icp/include"
+    "sys/modules/zfs"
+  ];
+  # nativeBuildInputs = [
+  #   bsdSetupHook freebsdSetupHook
+  #   makeMinimal install mandoc groff
+
+  #   flex byacc file2c
+  # ];
+  # buildInputs = compatIfNeeded ++ [ libnv libsbuf ];
+  meta.license = lib.licenses.cddl;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/libutil.nix b/pkgs/os-specific/bsd/freebsd/pkgs/libutil.nix
new file mode 100644
index 000000000000..c420d0daf852
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/libutil.nix
@@ -0,0 +1,7 @@
+{ mkDerivation, lib, stdenv }:
+mkDerivation {
+  path = "lib/libutil";
+  extraPaths = ["lib/libc/gen"];
+  clangFixup = true;
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/lorder.nix b/pkgs/os-specific/bsd/freebsd/pkgs/lorder.nix
new file mode 100644
index 000000000000..d1fd86ab5e46
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/lorder.nix
@@ -0,0 +1,20 @@
+{ mkDerivation
+, bsdSetupHook, freebsdSetupHook
+}:
+
+mkDerivation rec {
+  path = "usr.bin/lorder";
+  noCC = true;
+  dontBuild = true;
+  installPhase = ''
+    mkdir -p "$out/bin" "$man/share/man"
+    mv "lorder.sh" "$out/bin/lorder"
+    chmod +x "$out/bin/lorder"
+    mv "lorder.1" "$man/share/man"
+  '';
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+  ];
+  buildInputs = [];
+  outputs = [ "out" "man" ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/make.nix b/pkgs/os-specific/bsd/freebsd/pkgs/make.nix
new file mode 100644
index 000000000000..fa1722cfec22
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/make.nix
@@ -0,0 +1,20 @@
+{ lib, mkDerivation, stdenv }:
+
+mkDerivation {
+  path = "contrib/bmake";
+  version = "9.2";
+  postPatch = ''
+    # make needs this to pick up our sys make files
+    export NIX_CFLAGS_COMPILE+=" -D_PATH_DEFSYSPATH=\"$out/share/mk\""
+
+  '' + lib.optionalString stdenv.isDarwin ''
+    substituteInPlace $BSDSRCDIR/share/mk/bsd.sys.mk \
+      --replace '-Wl,--fatal-warnings' "" \
+      --replace '-Wl,--warn-shared-textrel' ""
+  '';
+  postInstall = ''
+    make -C $BSDSRCDIR/share/mk FILESDIR=$out/share/mk install
+  '';
+  extraPaths = [ "share/mk" ]
+    ++ lib.optional (!stdenv.hostPlatform.isFreeBSD) "tools/build/mk";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/makeMinimal.nix b/pkgs/os-specific/bsd/freebsd/pkgs/makeMinimal.nix
new file mode 100644
index 000000000000..e6a8e38a4ace
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/makeMinimal.nix
@@ -0,0 +1,61 @@
+{ lib, stdenv, mkDerivation
+, make
+, bsdSetupHook, freebsdSetupHook
+}:
+
+mkDerivation rec {
+  inherit (make) path;
+
+  buildInputs = [];
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+  ];
+
+  skipIncludesPhase = true;
+
+  makeFlags = [];
+
+  postPatch = ''
+    patchShebangs configure
+    ${make.postPatch}
+  '';
+
+  buildPhase = ''
+    runHook preBuild
+
+    sh ./make-bootstrap.sh
+
+    runHook postBuild
+  '';
+
+  installPhase = ''
+    runHook preInstall
+
+    install -D bmake "$out/bin/bmake"
+    ln -s "$out/bin/bmake" "$out/bin/make"
+    mkdir -p "$out/share"
+    cp -r "$BSDSRCDIR/share/mk" "$out/share/mk"
+    find "$out/share/mk" -type f -print0 |
+      while IFS= read -r -d "" f; do
+        substituteInPlace "$f" --replace 'usr/' ""
+      done
+    substituteInPlace "$out/share/mk/bsd.symver.mk" \
+      --replace '/share/mk' "$out/share/mk"
+
+    runHook postInstall
+  '';
+
+  postInstall = lib.optionalString (!stdenv.targetPlatform.isFreeBSD) ''
+    boot_mk="$BSDSRCDIR/tools/build/mk"
+    cp "$boot_mk"/Makefile.boot* "$out/share/mk"
+    replaced_mk="$out/share/mk.orig"
+    mkdir "$replaced_mk"
+    mv "$out"/share/mk/bsd.{lib,prog}.mk "$replaced_mk"
+    for m in bsd.{lib,prog}.mk; do
+      cp "$boot_mk/$m" "$out/share/mk"
+      substituteInPlace "$out/share/mk/$m" --replace '../../../share/mk' '../mk.orig'
+    done
+  '';
+
+  extraPaths = make.extraPaths;
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/mkDerivation.nix b/pkgs/os-specific/bsd/freebsd/pkgs/mkDerivation.nix
new file mode 100644
index 000000000000..14c9f0405534
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/mkDerivation.nix
@@ -0,0 +1,78 @@
+{ lib, stdenv, stdenvNoCC
+, compatIfNeeded
+, runCommand, rsync
+, freebsd-lib
+, freebsdSrc
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal
+, install, tsort, lorder, mandoc, groff
+}:
+
+lib.makeOverridable (attrs: let
+  stdenv' = if attrs.noCC or false then stdenvNoCC else stdenv;
+in stdenv'.mkDerivation (rec {
+  pname = "${attrs.pname or (baseNameOf attrs.path)}-freebsd";
+  inherit (freebsd-lib) version;
+  src = runCommand "${pname}-filtered-src" {
+    nativeBuildInputs = [ rsync ];
+  } ''
+    for p in ${lib.concatStringsSep " " ([ attrs.path ] ++ attrs.extraPaths or [])}; do
+      set -x
+      path="$out/$p"
+      mkdir -p "$(dirname "$path")"
+      src_path="${freebsdSrc}/$p"
+      if [[ -d "$src_path" ]]; then src_path+=/; fi
+      rsync --chmod="+w" -r "$src_path" "$path"
+      set +x
+    done
+  '';
+
+  extraPaths = [ ];
+
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal
+    install tsort lorder mandoc groff #statHook
+  ];
+  buildInputs = compatIfNeeded;
+
+  HOST_SH = stdenv'.shell;
+
+  # Since STRIP below is the flag
+  STRIPBIN = "${stdenv.cc.bintools.targetPrefix}strip";
+
+  makeFlags = [
+    "STRIP=-s" # flag to install, not command
+  ] ++ lib.optional (!stdenv.hostPlatform.isFreeBSD) "MK_WERROR=no";
+
+  # amd64 not x86_64 for this on unlike NetBSD
+  MACHINE_ARCH = freebsd-lib.mkBsdArch stdenv';
+
+  MACHINE = freebsd-lib.mkBsdArch stdenv';
+
+  MACHINE_CPUARCH = MACHINE_ARCH;
+
+  COMPONENT_PATH = attrs.path or null;
+
+  strictDeps = true;
+
+  meta = with lib; {
+    maintainers = with maintainers; [ ericson2314 ];
+    platforms = platforms.unix;
+    license = licenses.bsd2;
+  };
+} // lib.optionalAttrs stdenv'.hasCC {
+  # TODO should CC wrapper set this?
+  CPP = "${stdenv'.cc.targetPrefix}cpp";
+} // lib.optionalAttrs stdenv'.isDarwin {
+  MKRELRO = "no";
+} // lib.optionalAttrs (stdenv'.cc.isClang or false) {
+  HAVE_LLVM = lib.versions.major (lib.getVersion stdenv'.cc.cc);
+} // lib.optionalAttrs (stdenv'.cc.isGNU or false) {
+  HAVE_GCC = lib.versions.major (lib.getVersion stdenv'.cc.cc);
+} // lib.optionalAttrs (stdenv'.isx86_32) {
+  USE_SSP = "no";
+} // lib.optionalAttrs (attrs.headersOnly or false) {
+  installPhase = "includesPhase";
+  dontBuild = true;
+} // attrs))
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/mknod.nix b/pkgs/os-specific/bsd/freebsd/pkgs/mknod.nix
new file mode 100644
index 000000000000..56dff7d606bd
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/mknod.nix
@@ -0,0 +1,5 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "sbin/mknod";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/mtree.nix b/pkgs/os-specific/bsd/freebsd/pkgs/mtree.nix
new file mode 100644
index 000000000000..23a4672069e6
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/mtree.nix
@@ -0,0 +1,6 @@
+{ mkDerivation, mknod }:
+
+mkDerivation {
+  path = "contrib/mtree";
+  extraPaths = [ mknod.path ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/rpcgen/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/rpcgen/package.nix
new file mode 100644
index 000000000000..56141255af5e
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/rpcgen/package.nix
@@ -0,0 +1,22 @@
+{ lib, mkDerivation, stdenv }:
+
+mkDerivation rec {
+  path = "usr.bin/rpcgen";
+  patches = lib.optionals (stdenv.hostPlatform.libc == "glibc") [
+    # `WUNTRACED` is defined privately `bits/waitflags.h` in glibc.
+    # But instead of having a regular header guard, it has some silly
+    # non-modular logic. `stdlib.h` will include it if `sys/wait.h`
+    # hasn't yet been included (for it would first), and vice versa.
+    #
+    # The problem is that with the FreeBSD compat headers, one of
+    # those headers ends up included other headers...which ends up
+    # including the other one, this means by the first time we reach
+    # `#include `<bits/waitflags.h>`, both `_SYS_WAIT_H` and
+    # `_STDLIB_H` are already defined! Thus, we never ned up including
+    # `<bits/waitflags.h>` and defining `WUNTRACED`.
+    #
+    # This hacks around this by manually including `WUNTRACED` until
+    # the problem is fixed properly in glibc.
+    ./rpcgen-glibc-hack.patch
+  ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/rpcgen-glibc-hack.patch b/pkgs/os-specific/bsd/freebsd/pkgs/rpcgen/rpcgen-glibc-hack.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/rpcgen-glibc-hack.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/rpcgen/rpcgen-glibc-hack.patch
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/sed.nix b/pkgs/os-specific/bsd/freebsd/pkgs/sed.nix
new file mode 100644
index 000000000000..6532506b3fc2
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/sed.nix
@@ -0,0 +1,7 @@
+{ mkDerivation, freebsdSrc }:
+
+mkDerivation {
+  path = "usr.bin/sed";
+  TESTSRC = "${freebsdSrc}/contrib/netbsd-tests";
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/stat.nix b/pkgs/os-specific/bsd/freebsd/pkgs/stat.nix
new file mode 100644
index 000000000000..c730f00869f8
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/stat.nix
@@ -0,0 +1,13 @@
+{ mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+}:
+
+# Don't add this to nativeBuildInputs directly.  Use statHook instead.
+mkDerivation {
+  path = "usr.bin/stat";
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+  ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/statHook.nix b/pkgs/os-specific/bsd/freebsd/pkgs/statHook.nix
new file mode 100644
index 000000000000..07129938b095
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/statHook.nix
@@ -0,0 +1,12 @@
+{ makeSetupHook, writeText, stat }:
+
+# stat isn't in POSIX, and NetBSD stat supports a completely
+# different range of flags than GNU stat, so including it in PATH
+# breaks stdenv.  Work around that with a hook that will point
+# NetBSD's build system and NetBSD stat without including it in
+# PATH.
+makeSetupHook {
+  name = "netbsd-stat-hook";
+} (writeText "netbsd-stat-hook-impl" ''
+  makeFlagsArray+=(TOOL_STAT=${stat}/bin/stat)
+'')
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/sys/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/sys/package.nix
new file mode 100644
index 000000000000..81cf4114e873
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/sys/package.nix
@@ -0,0 +1,67 @@
+{ lib, stdenv, mkDerivation, freebsd-lib
+, buildPackages
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+, config, rpcgen, file2c, gawk, uudecode, xargs-j #, ctfconvert
+}:
+
+mkDerivation (let
+  cfg = "MINIMAL";
+in rec {
+  path = "sys";
+
+  nativeBuildInputs = [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+
+    config rpcgen file2c gawk uudecode xargs-j
+    #ctfconvert
+  ];
+
+  patches = [
+    ./sys-gnu-date.patch
+    ./sys-no-explicit-intrinsics-dep.patch
+  ];
+
+  # --dynamic-linker /red/herring is used when building the kernel.
+  NIX_ENFORCE_PURITY = 0;
+
+  AWK = "${buildPackages.gawk}/bin/awk";
+
+  CWARNEXTRA = "-Wno-error=shift-negative-value -Wno-address-of-packed-member";
+
+  MK_CTF = "no";
+
+  KODIR = "${builtins.placeholder "out"}/kernel";
+  KMODDIR = "${builtins.placeholder "out"}/kernel";
+  DTBDIR = "${builtins.placeholder"out"}/dbt";
+
+  KERN_DEBUGDIR = "${builtins.placeholder "out"}/debug";
+  KERN_DEBUGDIR_KODIR = "${KERN_DEBUGDIR}/kernel";
+  KERN_DEBUGDIR_KMODDIR = "${KERN_DEBUGDIR}/kernel";
+
+  skipIncludesPhase = true;
+
+  configurePhase = ''
+    runHook preConfigure
+
+    for f in conf/kmod.mk contrib/dev/acpica/acpica_prep.sh; do
+      substituteInPlace "$f" --replace 'xargs -J' 'xargs-j '
+    done
+
+    for f in conf/*.mk; do
+      substituteInPlace "$f" --replace 'KERN_DEBUGDIR}''${' 'KERN_DEBUGDIR_'
+    done
+
+    cd ${freebsd-lib.mkBsdArch stdenv}/conf
+    sed -i ${cfg} \
+      -e 's/WITH_CTF=1/WITH_CTF=0/' \
+      -e '/KDTRACE/d'
+    config ${cfg}
+
+    runHook postConfigure
+  '';
+  preBuild = ''
+    cd ../compile/${cfg}
+  '';
+})
diff --git a/pkgs/os-specific/bsd/freebsd/sys-gnu-date.patch b/pkgs/os-specific/bsd/freebsd/pkgs/sys/sys-gnu-date.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/sys-gnu-date.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/sys/sys-gnu-date.patch
diff --git a/pkgs/os-specific/bsd/freebsd/sys-no-explicit-intrinsics-dep.patch b/pkgs/os-specific/bsd/freebsd/pkgs/sys/sys-no-explicit-intrinsics-dep.patch
similarity index 100%
rename from pkgs/os-specific/bsd/freebsd/sys-no-explicit-intrinsics-dep.patch
rename to pkgs/os-specific/bsd/freebsd/pkgs/sys/sys-no-explicit-intrinsics-dep.patch
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/tsort.nix b/pkgs/os-specific/bsd/freebsd/pkgs/tsort.nix
new file mode 100644
index 000000000000..cdc1b27ce8fe
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/tsort.nix
@@ -0,0 +1,12 @@
+{ mkDerivation
+, bsdSetupHook, freebsdSetupHook
+, makeMinimal, install, mandoc, groff
+}:
+
+mkDerivation {
+  path = "usr.bin/tsort";
+  nativeBuildInputs =  [
+    bsdSetupHook freebsdSetupHook
+    makeMinimal install mandoc groff
+  ];
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/uudecode.nix b/pkgs/os-specific/bsd/freebsd/pkgs/uudecode.nix
new file mode 100644
index 000000000000..7e2341913dc0
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/uudecode.nix
@@ -0,0 +1,6 @@
+{ mkDerivation }:
+
+mkDerivation {
+  path = "usr.bin/uudecode";
+  MK_TESTS = "no";
+}
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/xargs-j/package.nix b/pkgs/os-specific/bsd/freebsd/pkgs/xargs-j/package.nix
new file mode 100644
index 000000000000..3a6b0ff00428
--- /dev/null
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/xargs-j/package.nix
@@ -0,0 +1,9 @@
+{ substituteAll, runtimeShell }:
+
+substituteAll {
+  name = "xargs-j";
+  shell = runtimeShell;
+  src = ./xargs-j.sh;
+  dir = "bin";
+  isExecutable = true;
+}
diff --git a/pkgs/os-specific/bsd/xargs-j.sh b/pkgs/os-specific/bsd/freebsd/pkgs/xargs-j/xargs-j.sh
similarity index 100%
rename from pkgs/os-specific/bsd/xargs-j.sh
rename to pkgs/os-specific/bsd/freebsd/pkgs/xargs-j/xargs-j.sh