diff --git a/maintainers/maintainer-list.nix b/maintainers/maintainer-list.nix
index 3c56c36d90c..59c0cd4997c 100644
--- a/maintainers/maintainer-list.nix
+++ b/maintainers/maintainer-list.nix
@@ -2233,6 +2233,12 @@
       fingerprint = "4749 0887 CF3B 85A1 6355  C671 78C7 DD40 DF23 FB16";
     }];
   };
+  dpercy = {
+    email = "dpercy@dpercy.dev";
+    github = "dpercy";
+    githubId = 349909;
+    name = "David Percy";
+  };
   dpflug = {
     email = "david@pflug.email";
     github = "dpflug";
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new file mode 100644
index 00000000000..86768d4611e
--- /dev/null
+++ b/pkgs/development/tools/build-managers/fac/cargo-lock.patch
@@ -0,0 +1,802 @@
+diff --git a/Cargo.lock b/Cargo.lock
+new file mode 100644
+index 0000000..4ab2c17
+--- /dev/null
++++ b/Cargo.lock
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++checksum = "200976cc4ff22cd8b9c6c23681fe6aa89a12aa3637c86dd16e44c05d7c373488"
++dependencies = [
++ "gcc",
++ "libc",
++ "pkg-config",
++]
++
++[[package]]
++name = "serde"
++version = "1.0.115"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "e54c9a88f2da7238af84b5101443f0c0d0a3bbdc455e34a5c9497b1903ed55d5"
++
++[[package]]
++name = "slab"
++version = "0.4.2"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "c111b5bd5695e56cffe5129854aa230b39c93a305372fdbb2668ca2394eea9f8"
++
++[[package]]
++name = "state"
++version = "0.4.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "7345c971d1ef21ffdbd103a75990a15eb03604fc8b8852ca8cb418ee1a099028"
++dependencies = [
++ "thread_local 0.3.3",
++]
++
++[[package]]
++name = "strsim"
++version = "0.8.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
++
++[[package]]
++name = "syn"
++version = "1.0.40"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "963f7d3cc59b59b9325165add223142bbf1df27655d07789f109896d353d8350"
++dependencies = [
++ "proc-macro2",
++ "quote",
++ "unicode-xid",
++]
++
++[[package]]
++name = "termcolor"
++version = "1.1.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "bb6bfa289a4d7c5766392812c0a1f4c1ba45afa1ad47803c11e1f407d846d75f"
++dependencies = [
++ "winapi-util",
++]
++
++[[package]]
++name = "textwrap"
++version = "0.11.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
++dependencies = [
++ "unicode-width",
++]
++
++[[package]]
++name = "thread-id"
++version = "3.3.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "c7fbf4c9d56b320106cd64fd024dadfa0be7cb4706725fc44a7d7ce952d820c1"
++dependencies = [
++ "libc",
++ "redox_syscall",
++ "winapi 0.3.9",
++]
++
++[[package]]
++name = "thread_local"
++version = "0.3.3"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "c85048c6260d17cf486ceae3282d9fb6b90be220bf5b28c400f5485ffc29f0c7"
++dependencies = [
++ "thread-id",
++ "unreachable",
++]
++
++[[package]]
++name = "thread_local"
++version = "1.0.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
++dependencies = [
++ "lazy_static 1.4.0",
++]
++
++[[package]]
++name = "tinyset"
++version = "0.4.4"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "784f540960a63144d63992caf430ed87e39d920f2c474cb8ac586ff31fb861fc"
++dependencies = [
++ "itertools",
++ "rand",
++]
++
++[[package]]
++name = "unicode-width"
++version = "0.1.8"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "9337591893a19b88d8d87f2cec1e73fad5cdfd10e5a6f349f498ad6ea2ffb1e3"
++
++[[package]]
++name = "unicode-xid"
++version = "0.2.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "f7fe0bb3479651439c9112f72b6c505038574c9fbb575ed1bf3b797fa39dd564"
++
++[[package]]
++name = "unreachable"
++version = "0.1.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "1f2ae5ddb18e1c92664717616dd9549dde73f539f01bd7b77c2edb2446bdff91"
++dependencies = [
++ "void",
++]
++
++[[package]]
++name = "vec_map"
++version = "0.8.2"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "f1bddf1187be692e79c5ffeab891132dfb0f236ed36a43c7ed39f1165ee20191"
++
++[[package]]
++name = "void"
++version = "1.0.2"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
++
++[[package]]
++name = "walkdir"
++version = "2.3.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "777182bc735b6424e1a57516d35ed72cb8019d85c8c9bf536dccb3445c1a2f7d"
++dependencies = [
++ "same-file",
++ "winapi 0.3.9",
++ "winapi-util",
++]
++
++[[package]]
++name = "wasi"
++version = "0.9.0+wasi-snapshot-preview1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
++
++[[package]]
++name = "winapi"
++version = "0.2.8"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
++
++[[package]]
++name = "winapi"
++version = "0.3.9"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
++dependencies = [
++ "winapi-i686-pc-windows-gnu",
++ "winapi-x86_64-pc-windows-gnu",
++]
++
++[[package]]
++name = "winapi-build"
++version = "0.1.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
++
++[[package]]
++name = "winapi-i686-pc-windows-gnu"
++version = "0.4.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
++
++[[package]]
++name = "winapi-util"
++version = "0.1.5"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
++dependencies = [
++ "winapi 0.3.9",
++]
++
++[[package]]
++name = "winapi-x86_64-pc-windows-gnu"
++version = "0.4.0"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
++
++[[package]]
++name = "ws2_32-sys"
++version = "0.2.1"
++source = "registry+https://github.com/rust-lang/crates.io-index"
++checksum = "d59cefebd0c892fa2dd6de581e937301d8552cb44489cdff035c6187cb63fa5e"
++dependencies = [
++ "winapi 0.2.8",
++ "winapi-build",
++]
diff --git a/pkgs/development/tools/build-managers/fac/default.nix b/pkgs/development/tools/build-managers/fac/default.nix
new file mode 100644
index 00000000000..8c41eb3ac51
--- /dev/null
+++ b/pkgs/development/tools/build-managers/fac/default.nix
@@ -0,0 +1,50 @@
+{ stdenv, git, fetchFromGitHub, rustPlatform }:
+
+rustPlatform.buildRustPackage rec {
+  pname = "fac-build";
+  version = "0.5.3";
+
+  src = fetchFromGitHub {
+    owner = "droundy";
+    repo = "fac";
+    rev = version;
+    sha256 = "1gifrlb31jy8633rnhny58ccp3wlmd338129c6sh0h1a38vkmsxk";
+  };
+
+  # workaround for missing Cargo.lock file
+  cargoPatches = [ ./cargo-lock.patch ];
+
+  cargoSha256 = "0hjfq61y1ikdcajr2k514k7fad2zxbwq7yb5nk1wx38f1524709q";
+
+  # fac includes a unit test called ls_files_works which assumes it's
+  # running in a git repo. Nix's sandbox runs cargo build outside git,
+  # so this test won't work.
+  checkFlagsArray = [ "--skip=ls_files_works" ];
+
+  # fac calls git at runtime, expecting it to be in the PATH,
+  # so we need to patch it to call git by absolute path instead.
+  postPatch = ''
+    substituteInPlace src/git.rs \
+        --replace 'std::process::Command::new("git")' \
+        'std::process::Command::new("${git}/bin/git")'
+  '';
+
+  meta = with stdenv.lib; {
+    description = ''
+      A build system that uses ptrace to handle dependencies automatically
+    '';
+    longDescription = ''
+      Fac is a general-purpose build system inspired by make that utilizes
+      ptrace to ensure that all dependences are enumerated and that all
+      source files are added to a (git) repo. An important feature of fac
+      is that it automatically handles dependencies, rather than either
+      complaining about them or giving an incorrect build. Currently, fac
+      only runs on linux systems, but on those systems it is incredibly
+      easy to use!
+    '';
+    homepage = "https://physics.oregonstate.edu/~roundyd/fac";
+    license = licenses.gpl2Plus;
+    platforms = platforms.linux;
+    maintainers = [ maintainers.dpercy ];
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 698b11a5bfd..fa293f56ba9 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -27981,4 +27981,6 @@ in
 
   unifi-poller = callPackage ../servers/monitoring/unifi-poller {};
 
+  fac-build = callPackage ../development/tools/build-managers/fac {};
+
 }