diff --git a/.build.yml b/.build.yml
deleted file mode 100644
index 6118817..0000000
--- a/.build.yml
+++ /dev/null
@@ -1,8 +0,0 @@
-image: nixos/unstable
-environment:
-  NIX_CONFIG: "experimental-features = nix-command flakes"
-packages:
-  - cachix
-tasks:
-  -build: |
-    nix build . -vL --no-out-link
diff --git a/.github/workflows/repo-lockdown.yml b/.github/workflows/repo-lockdown.yml
deleted file mode 100644
index e513c4f..0000000
--- a/.github/workflows/repo-lockdown.yml
+++ /dev/null
@@ -1,16 +0,0 @@
-name: "Repo Lockdown"
-
-on:
-  pull_request_target:
-    types: 'opened'
-
-permissions:
-  pull-requests: write
-
-jobs:
-  action:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: dessant/repo-lockdown@v4
-        with:
-          pr-comment: "This repo does not accept pull requests as it is a mirror. Please instead submit patches to https://sr.ht/~bryan_bennett/flake_env."
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
deleted file mode 100644
index 3d7a1b5..0000000
--- a/.github/workflows/test.yml
+++ /dev/null
@@ -1,14 +0,0 @@
-name: "Test"
-on:
-  pull_request:
-  push:
-jobs:
-  tests:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-    - uses: cachix/install-nix-action@v25
-      with:
-        github_access_token: ${{ secrets.GITHUB_TOKEN }}
-    - run: nix build
-    - run: nix flake check --all-systems --keep-going
diff --git a/.gitignore b/.gitignore
deleted file mode 100644
index 65c12c2..0000000
--- a/.gitignore
+++ /dev/null
@@ -1,4 +0,0 @@
-_build/
-_coverage/
-result
-/.pre-commit-config.yaml
\ No newline at end of file
diff --git a/.ocamlformat b/.ocamlformat
deleted file mode 100644
index 40137a6..0000000
--- a/.ocamlformat
+++ /dev/null
@@ -1,2 +0,0 @@
-version=0.26.1
-profile=default
\ No newline at end of file
diff --git a/Justfile b/Justfile
deleted file mode 100644
index 6bcf045..0000000
--- a/Justfile
+++ /dev/null
@@ -1,10 +0,0 @@
-build:
-	@dune build
-
-test:
-	@dune test -f
-	@bisect-ppx-report html
-	@bisect-ppx-report summary --per-file
-
-fmt:
-	@dune build @fmt --auto-promote
diff --git a/README.md b/README.md
index 53a8b09..9d3ac9d 100644
--- a/README.md
+++ b/README.md
@@ -40,13 +40,6 @@ watch_file **/*.nix
 use flake_env .
 ```
 
-## Developing
-
-This repo uses [just](https://just.systems/) to manage simple build jobs.
-After activating the development environment in the repo, run `just -l`  to list tasks.
-
-Please remember to format code before issuing patches.
-
 ## Credits
 
 This takes huge inspiration (and literal code-chunks) from nix-direnv. 
diff --git a/bin/dune b/bin/dune
index 186c456..9b0e082 100644
--- a/bin/dune
+++ b/bin/dune
@@ -1,14 +1,5 @@
 (executable
- (name flake_env)
- (public_name flake_env)
- (libraries
-  core
-  core_unix
-  core_unix.filename_unix
-  core_unix.sys_unix
-  ppx_yojson_conv
-  re
-  sha
-  lib)
- (preprocess
-  (pps ppx_yojson_conv ppx_jane)))
+  (name flake_env)
+  (public_name flake_env)
+  (libraries core core_unix core_unix.filename_unix core_unix.sys_unix ppx_yojson_conv re sha lib)
+  (preprocess (pps ppx_yojson_conv ppx_jane)))
\ No newline at end of file
diff --git a/bin/flake_env.re b/bin/flake_env.re
index 1c147a3..e9845c3 100644
--- a/bin/flake_env.re
+++ b/bin/flake_env.re
@@ -1,64 +1,149 @@
 open Core;
 module Unix = Core_unix;
 
-open Lib;
 
-let main = () => {
-  let argv = Sys.get_argv();
-  switch (Util.get_args(argv)) {
-  | Ok((layout_directory, flake_specifier, other_args)) =>
-    switch (preflight(layout_directory)) {
-    | Ok () =>
-      switch (Lib.Watches.get()) {
-      | Ok(watches) =>
-        let paths = Array.map(~f=watch => watch.path, watches);
-        let hash =
-          switch (Util.hash_files(paths)) {
-          | Ok(hsh) => hsh
-          | Error(msg) =>
-            Printf.eprintf("%s\n", msg);
-            exit(1);
-          };
-
-        let profile = layout_directory ++ "/flake-profile-" ++ hash;
-        let profile_rc = profile ++ ".rc";
-
-        switch (Sys_unix.is_file(profile_rc), Sys_unix.is_file(profile)) {
-        | (`Yes, `Yes) =>
-          let profile_rc_mtime = Unix.stat(profile_rc).st_mtime;
-          let all_older =
-            Array.map(~f=watch => watch.modtime, watches)
-            |> Array.for_all(~f=watch_mtime =>
-                 watch_mtime <= int_of_float(profile_rc_mtime)
-               );
-          if (all_older) {
-            print_cur_cache(profile_rc);
-          } else {
-            freshen_cache(
-              layout_directory,
-              hash,
-              flake_specifier,
-              other_args,
-            );
-          };
-        | _ =>
-          freshen_cache(layout_directory, hash, flake_specifier, other_args)
-        };
-      | Error(e) =>
-        Printf.eprintf("%s\n", e);
-        exit(1);
-      }
-    | Error(e) =>
-      Printf.eprintf("%s\n", e);
-      exit(1);
+let preflight = (layout_directory) => {
+  switch (Lib.Versions.preflight_versions(), Sys_unix.is_directory(layout_directory)) {
+    | (Ok(_), `Yes) => Ok()
+    | (Ok(_), _) => {
+      Unix.mkdir_p(layout_directory);
+      Ok()
     }
-  | Error () =>
-    Printf.eprintf(
-      "%s  <layout_directory> <flake specifier> <...args>\n",
-      argv[0],
-    );
-    exit(1);
-  };
+    | (err, _) => err
+  }
+}
+
+let hash_files = (filenames) => {
+  let ctx = Sha1.init();
+  let () = filenames
+  |> Array.filter(~f=f => switch (Sys_unix.file_exists(f)) {
+      | `Yes => true
+      | _ => false
+    })
+  |> Array.iter(~f=(f) => {
+    f |> In_channel.create |> In_channel.input_all |> Sha1.update_string(ctx);
+  });
+  Sha1.finalize(ctx) |> Sha1.to_hex
 };
 
+// TODO: Maybe make this more terse?
+let rec rmrf = (path) => {
+  switch (Unix.lstat(path).st_kind) {
+  | exception Unix.Unix_error(_, _, _) => ()
+  | S_REG => Unix.unlink(path)
+  | S_LNK => Unix.unlink(path)
+  | S_DIR => {
+      Sys_unix.readdir(path) |> Array.iter(~f=name => rmrf(Filename.concat(path, name)));
+      Unix.rmdir(path)
+    }
+  | S_CHR => Printf.eprintf("Don't know how to handle Character Device file\n")
+  | S_BLK => Printf.eprintf("Don't know how to handle Block Device file\n")
+  | S_FIFO => Printf.eprintf("Don't know how to handle FIFO file\n")
+  | S_SOCK => Printf.eprintf("Don't know how to handle Socket file\n")
+  }
+};
+
+let clean_old_gcroots = (layout_dir) => {
+  rmrf(layout_dir ++ "/flake-inputs/");
+  rmrf(layout_dir);
+  Unix.mkdir_p(layout_dir ++ "/flake-inputs/");
+};
+
+let print_cur_cache = (profile_rc) => {
+  In_channel.read_all(profile_rc) |> Printf.printf("%s")
+};
+
+let add_gcroot = (store_path, symlink) => {
+  switch (Lib.Util.nix(["build", "--out-link", symlink, store_path])) {
+  | (Ok(), _) => Ok()
+  | (err, _) => err
+  }
+}
+
+let freshen_cache = (layout_dir, hash, flake_specifier) => {
+  clean_old_gcroots(layout_dir);
+  let tmp_profile = layout_dir ++ "flake-tmp-profile."  ++ Core.Pid.to_string(Core_unix.getpid());
+  let (exit_code, stdout_content) = Lib.Util.nix(["print-dev-env", "--profile", tmp_profile, flake_specifier]);
+
+  let profile = layout_dir ++ "/flake-profile-" ++ hash;
+  let profile_rc = profile ++ ".rc";
+
+  switch (exit_code) {
+  | Ok() => {
+      Out_channel.with_file(~f=f=> Out_channel.output_string(f, stdout_content), profile_rc);
+      switch (add_gcroot(tmp_profile, profile)) {
+        | Ok() => {
+          Sys_unix.remove(tmp_profile);
+          let flake_input_cache_path = layout_dir ++ "/flake-inputs/"
+          let flake_inputs = Lib.Watches.get_input_paths();
+          flake_inputs |> List.iter(~f=(inpt) => {
+            switch (add_gcroot("/nix/store/" ++ inpt, flake_input_cache_path ++ inpt)) {
+            | Ok() => ()
+            | err => Printf.eprintf("Failed creating flake-input gcroot: %s\n", Core_unix.Exit_or_signal.to_string_hum(err));
+            };
+          });
+          print_cur_cache(profile_rc);
+        }
+        | err => {
+          Printf.eprintf("Failed creating gcroot: %s\n", Core_unix.Exit_or_signal.to_string_hum(err));
+          exit(1);
+        }
+      };
+    }
+  | err => {
+      Printf.eprintf("Failed evaluating flake: %s\n", Core_unix.Exit_or_signal.to_string_hum(err));
+      exit(1);
+    }
+  };
+
+};
+
+// TODO: Extend to add support for additional flags, maybe?
+let main = () => {
+  let argv = Sys.get_argv();
+  switch (Array.length(argv)) {
+  | 3 => {
+      let flake_specifier = argv[1];
+      let layout_directory = argv[2];
+      switch (preflight(layout_directory)) {
+        | Ok() => {
+            switch (Lib.Watches.get()) {
+            | Ok(watches) => {
+                let paths = Array.map(~f=watch => watch.path, watches);
+                let hash = hash_files(paths);
+                let profile = layout_directory ++ "/flake-profile-" ++ hash;
+                let profile_rc = profile ++ ".rc";
+
+                switch ((Sys_unix.is_file(profile_rc), Sys_unix.is_file(profile))) {
+                | (`Yes, `Yes) => {
+                    let profile_rc_mtime = Unix.stat(profile_rc).st_mtime;
+                    let all_older= Array.map(~f=watch => watch.modtime, watches)
+                    |> Array.for_all(~f=watch_mtime => watch_mtime <= int_of_float(profile_rc_mtime))
+                    switch (all_older) {
+                    | true => print_cur_cache(profile_rc)
+                    | false => freshen_cache(layout_directory, hash, flake_specifier)
+                    }
+                  }
+                | _ => freshen_cache(layout_directory, hash, flake_specifier)
+                }
+              };
+            | Error(e) => {
+                Printf.eprintf("%s\n", e);
+                exit(1);
+              }
+            }
+          }
+      | Error(e) => {
+          Printf.eprintf("%s\n", e);
+          exit(1);
+        }
+      };
+    }
+  | _ => {
+      Printf.eprintf("%s <flake specifier> <layout_directory>\n", argv[0]);
+      exit(1);
+      }
+  }
+}
+
 let () = main();
diff --git a/default.nix b/default.nix
index 7b4b0a7..0ef7fe8 100644
--- a/default.nix
+++ b/default.nix
@@ -1,10 +1,6 @@
-{ alcotest
-, bintools
-, bisect_ppx
-, buildDunePackage
+{ buildDunePackage
 , core
 , core_unix
-, coreutils
 , findlib
 , lib
 , nix-filter
@@ -14,8 +10,6 @@
 , re
 , reason
 , sha
-, upx
-,
 }:
 buildDunePackage {
   pname = "flake_env";
@@ -25,7 +19,6 @@ buildDunePackage {
     include = [
       "bin"
       "lib"
-      "tests"
       ./dune-project
       ./flake.nix
       ./default.nix
@@ -35,26 +28,25 @@ buildDunePackage {
     ];
   };
   duneVersion = "3";
-  doCheck = true;
   postPatch = ''
     substituteInPlace direnvrc --replace "@flake_env@" "$out/bin/flake_env"
-    substituteInPlace tests/spit*.sh --replace "/usr/bin/env" "${coreutils}/bin/env"
   '';
   postInstall = ''
-    ${bintools}/bin/strip --strip-unneeded $out/bin/flake_env
-    ${upx}/bin/upx $out/bin/flake_env
     install -m400 -D direnvrc $out/share/flake_env/direnvrc
   '';
-  buildInputs = [
+  nativeBuildInputs = [
+    reason
+  ];
+  propagatedBuildInputs = [
     core
     core_unix
+    findlib
+    ocaml
     ppx_yojson_conv
     ppx_yojson_conv_lib
     re
     sha
   ];
-  checkInputs = [ alcotest bisect_ppx ];
-  nativeBuildInputs = [ reason ];
 
   meta = with lib; {
     description = "Yet another flake plugin for direnv";
diff --git a/direnvrc b/direnvrc
index 85cc4bc..c498f73 100644
--- a/direnvrc
+++ b/direnvrc
@@ -41,7 +41,7 @@ use_flake_env() {
   local ld=$(direnv_layout_dir)
   export direnv
 
-  eval "$(@flake_env@ "${1:-"."}" "$ld")"
+  eval "$(@flake_env@ "$1" "$ld")"
 
   export -n direnv
 
diff --git a/dune-project b/dune-project
index 88a33ec..063ff61 100644
--- a/dune-project
+++ b/dune-project
@@ -1,11 +1,18 @@
 (lang dune 3.11)
 
 (name flake_env)
+
 (generate_opam_files true)
-(source (sourcehut bryan_bennett/flake_env))
+
+(source
+ (sourcehut bryan_bennett/flake_env))
+
 (authors "Bryan Bennett")
+
 (maintainers "Bryan Bennett")
+
 (license MIT)
+
 (documentation https://git.sr.ht/~bryan_bennett/flake_env)
 
 (package
diff --git a/dune-workspace b/dune-workspace
deleted file mode 100644
index 42130a0..0000000
--- a/dune-workspace
+++ /dev/null
@@ -1,2 +0,0 @@
-(lang dune 3.11)
-(instrument_with bisect_ppx)
\ No newline at end of file
diff --git a/flake.lock b/flake.lock
index 0cfb382..a1e8315 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,21 +1,5 @@
 {
   "nodes": {
-    "flake-compat": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1696426674,
-        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
-        "type": "github"
-      },
-      "original": {
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "type": "github"
-      }
-    },
     "flake-parts": {
       "inputs": {
         "nixpkgs-lib": [
@@ -23,11 +7,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1709336216,
-        "narHash": "sha256-Dt/wOWeW6Sqm11Yh+2+t0dfEWxoMxGBvv3JpIocFl9E=",
+        "lastModified": 1701473968,
+        "narHash": "sha256-YcVE5emp1qQ8ieHUnxt1wCZCC3ZfAS+SRRWZ2TMda7E=",
         "owner": "hercules-ci",
         "repo": "flake-parts",
-        "rev": "f7b3c975cf067e56e7cda6cb098ebe3fb4d74ca2",
+        "rev": "34fed993f1674c8d06d58b37ce1e0fe5eebcb9f5",
         "type": "github"
       },
       "original": {
@@ -36,52 +20,13 @@
         "type": "github"
       }
     },
-    "flake-utils": {
-      "inputs": {
-        "systems": "systems"
-      },
-      "locked": {
-        "lastModified": 1710146030,
-        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "gitignore": {
-      "inputs": {
-        "nixpkgs": [
-          "pre-commit-hooks",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1709087332,
-        "narHash": "sha256-HG2cCnktfHsKV0s4XW83gU3F57gaTljL9KNSuG6bnQs=",
-        "owner": "hercules-ci",
-        "repo": "gitignore.nix",
-        "rev": "637db329424fd7e46cf4185293b9cc8c88c95394",
-        "type": "github"
-      },
-      "original": {
-        "owner": "hercules-ci",
-        "repo": "gitignore.nix",
-        "type": "github"
-      }
-    },
     "nix-filter": {
       "locked": {
-        "lastModified": 1710156097,
-        "narHash": "sha256-1Wvk8UP7PXdf8bCCaEoMnOT1qe5/Duqgj+rL8sRQsSM=",
+        "lastModified": 1701697642,
+        "narHash": "sha256-L217WytWZHSY8GW9Gx1A64OnNctbuDbfslaTEofXXRw=",
         "owner": "numtide",
         "repo": "nix-filter",
-        "rev": "3342559a24e85fc164b295c3444e8a139924675b",
+        "rev": "c843418ecfd0344ecb85844b082ff5675e02c443",
         "type": "github"
       },
       "original": {
@@ -92,11 +37,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1711106783,
-        "narHash": "sha256-PDwAcHahc6hEimyrgGmFdft75gmLrJOZ0txX7lFqq+I=",
+        "lastModified": 1702272962,
+        "narHash": "sha256-D+zHwkwPc6oYQ4G3A1HuadopqRwUY/JkMwHz1YF7j4Q=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "a3ed7406349a9335cb4c2a71369b697cecd9d351",
+        "rev": "e97b3e4186bcadf0ef1b6be22b8558eab1cdeb5d",
         "type": "github"
       },
       "original": {
@@ -106,81 +51,11 @@
         "type": "github"
       }
     },
-    "nixpkgs-stable": {
-      "locked": {
-        "lastModified": 1710695816,
-        "narHash": "sha256-3Eh7fhEID17pv9ZxrPwCLfqXnYP006RKzSs0JptsN84=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "614b4613980a522ba49f0d194531beddbb7220d3",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixos-23.11",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs_2": {
-      "locked": {
-        "lastModified": 1710765496,
-        "narHash": "sha256-p7ryWEeQfMwTB6E0wIUd5V2cFTgq+DRRBz2hYGnJZyA=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "e367f7a1fb93137af22a3908f00b9a35e2d286a7",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixpkgs-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "pre-commit-hooks": {
-      "inputs": {
-        "flake-compat": "flake-compat",
-        "flake-utils": "flake-utils",
-        "gitignore": "gitignore",
-        "nixpkgs": "nixpkgs_2",
-        "nixpkgs-stable": "nixpkgs-stable"
-      },
-      "locked": {
-        "lastModified": 1710923068,
-        "narHash": "sha256-6hOpUiuxuwpXXc/xfJsBUJeqqgGI+JMJuLo45aG3cKc=",
-        "owner": "cachix",
-        "repo": "pre-commit-hooks.nix",
-        "rev": "e611897ddfdde3ed3eaac4758635d7177ff78673",
-        "type": "github"
-      },
-      "original": {
-        "owner": "cachix",
-        "repo": "pre-commit-hooks.nix",
-        "type": "github"
-      }
-    },
     "root": {
       "inputs": {
         "flake-parts": "flake-parts",
         "nix-filter": "nix-filter",
-        "nixpkgs": "nixpkgs",
-        "pre-commit-hooks": "pre-commit-hooks"
-      }
-    },
-    "systems": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
+        "nixpkgs": "nixpkgs"
       }
     }
   },
diff --git a/flake.nix b/flake.nix
index b61bbff..12bcdb7 100644
--- a/flake.nix
+++ b/flake.nix
@@ -6,70 +6,42 @@
       url = "github:hercules-ci/flake-parts";
       inputs.nixpkgs-lib.follows = "nixpkgs";
     };
-    pre-commit-hooks = { url = "github:cachix/pre-commit-hooks.nix"; };
-    nix-filter = { url = "github:numtide/nix-filter"; };
+    nix-filter = {
+      url = "github:numtide/nix-filter";
+    };
   };
 
-  outputs =
-    inputs @ { flake-parts
-    , nix-filter
-    , pre-commit-hooks
-    , ...
-    }:
-    flake-parts.lib.mkFlake { inherit inputs; } ({ lib, ... }: {
-      systems = [
-        "aarch64-linux"
-        "x86_64-linux"
+  outputs = inputs @ { flake-parts, nix-filter, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; }
+      ({ lib, ... }: {
+        systems = [
+          "aarch64-linux"
+          "x86_64-linux"
 
-        "x86_64-darwin"
-        "aarch64-darwin"
-      ];
-      imports = [ pre-commit-hooks.flakeModule ];
-      perSystem =
-        { config
-        , pkgs
-        , self'
-        , ...
-        }: {
+          "x86_64-darwin"
+          "aarch64-darwin"
+        ];
+        perSystem = { config, pkgs, self', ... }: {
           packages = {
-            flake_env = pkgs.ocamlPackages.callPackage ./default.nix {
-              inherit nix-filter;
-            };
+            flake_env = pkgs.ocamlPackages.callPackage ./default.nix { inherit nix-filter; };
             default = config.packages.flake_env;
           };
           devShells.default = pkgs.mkShell {
             inputsFrom = [ self'.packages.default ];
-            packages = builtins.attrValues {
-              inherit (pkgs)
-                just
-                nil
-                pre-commit
-                ;
-              inherit (pkgs.ocamlPackages)
-                dune_3
-                findlib
-                ocaml
-                ocaml-lsp
-                ocamlformat
-                ocamlformat-rpc-lib
-                ;
-            };
-            shellHook = config.pre-commit.installationScript;
-          };
-          pre-commit = {
-            check.enable = true;
-            settings.hooks = {
-              nixpkgs-fmt.enable = true;
-              dune-fmt.enable = true;
-            };
+            packages = [
+              pkgs.ocamlPackages.dune_3
+              pkgs.ocamlPackages.findlib
+              pkgs.ocamlPackages.ocaml
+              pkgs.ocamlPackages.ocaml-lsp
+              pkgs.ocamlPackages.ocamlformat
+              pkgs.ocamlPackages.ocamlformat-rpc-lib
+            ];
           };
         };
-      flake = {
-        overlays.default = final: _prev: {
-          flake_env = final.ocamlPackages.callPackage ./default.nix {
-            inherit nix-filter;
+        flake = {
+          overlays.default = final: _prev: {
+            flake_env = final.ocamlPackages.callPackage ./default.nix { inherit nix-filter; };
           };
         };
-      };
-    });
+      });
 }
diff --git a/lib/dune b/lib/dune
index 168d405..6e33744 100644
--- a/lib/dune
+++ b/lib/dune
@@ -1,15 +1,5 @@
 (library
- (name lib)
- (public_name flake_env.lib)
- (libraries
-  core
-  core_unix
-  core_unix.filename_unix
-  core_unix.sys_unix
-  ppx_yojson_conv
-  re
-  sha)
- (instrumentation
-  (backend bisect_ppx))
- (preprocess
-  (pps ppx_yojson_conv ppx_jane)))
+  (name lib)
+  (public_name flake_env.lib)
+  (libraries core core_unix core_unix.filename_unix core_unix.sys_unix ppx_yojson_conv re sha)
+  (preprocess (pps ppx_yojson_conv ppx_jane ppx_inline_test)))
\ No newline at end of file
diff --git a/lib/flake_env__util.re b/lib/flake_env__util.re
index e471010..e05c1fa 100644
--- a/lib/flake_env__util.re
+++ b/lib/flake_env__util.re
@@ -1,80 +1,10 @@
 open Core;
 module Unix = Core_unix;
 
-let run_process = (name, args) => {
-  /*** Run a process [name] with args [args], returning (exit_code, stdout text) */
-  let stdout_chan =
-    Unix.open_process_in(name ++ " " ++ (args |> String.concat(~sep=" ")));
+let nix = (args) => {
+  let stdout_chan = Unix.open_process_in(
+    "nix --extra-experimental-features \"nix-command flakes\" " ++ (args |> String.concat(~sep=" ")));
   let stdout_content = stdout_chan |> In_channel.input_all;
   let exit_code = Unix.close_process_in(stdout_chan);
-  (exit_code, stdout_content);
-};
-
-let nix = args =>
-  run_process(
-    "nix",
-    ["--extra-experimental-features", "\"nix-command flakes\" ", ...args],
-  );
-
-let hash_files = filenames => {
-  /*** Hash all entries in [filenames]
-         Returns Some(hex-string) or None if no filenames are found.
-       */
-  let ctx = Sha1.init();
-  let files_to_hash =
-    filenames
-    |> Array.filter(~f=f =>
-         switch (Sys_unix.file_exists(f)) {
-         | `Yes => true
-         | _ =>
-           // let fullpth = Filename_unix.realpath(f);
-           Printf.eprintf(
-             "Cannot find file %s (cwd: %s)\n",
-             f,
-             Core_unix.getcwd(),
-           );
-           false;
-         }
-       );
-
-  switch (files_to_hash |> Array.length) {
-  | 0 => Error("No files found to hash")
-  | _ =>
-    let () =
-      files_to_hash
-      |> Array.iter(~f=f => {
-           f
-           |> In_channel.create
-           |> In_channel.input_all
-           |> Sha1.update_string(ctx)
-         });
-    Ok(Sha1.finalize(ctx) |> Sha1.to_hex);
-  };
-};
-
-let rec rmrf = path => {
-  switch (Unix.lstat(path).st_kind) {
-  | exception (Unix.Unix_error(_, _, _)) => ()
-  | S_REG
-  | S_LNK => Unix.unlink(path)
-  | S_DIR =>
-    Sys_unix.readdir(path)
-    |> Array.iter(~f=name => rmrf(Filename.concat(path, name)));
-    Unix.rmdir(path);
-  | _ =>
-    Printf.eprintf(
-      "Unsupported file type (Chr or Block device, FIFO, or Socket)\n",
-    )
-  };
-};
-
-let get_args = argv => {
-  switch (Array.length(argv)) {
-  | x when x >= 3 =>
-    let layout_directory = argv[1];
-    let flake_specifier = argv[2];
-    let other_args = snd(List.split_n(List.of_array(argv), 3));
-    Ok((layout_directory, flake_specifier, other_args));
-  | _ => Error()
-  };
-};
+  (exit_code, stdout_content)
+}
diff --git a/lib/flake_env__versions.re b/lib/flake_env__versions.re
index c36fb04..2430daf 100644
--- a/lib/flake_env__versions.re
+++ b/lib/flake_env__versions.re
@@ -1,84 +1,82 @@
 open Core;
 module Unix = Core_unix;
 
-module Util = Flake_env__util;
-
 type t = {
   major: int,
   minor: int,
   point: int,
 };
 
-let init = (major, minor, point) => {major, minor, point};
-
-let required_direnv_version = init(2, 21, 3);
-
-let required_nix_version = init(2, 10, 0);
-
 let semver_re = Re.compile(Re.Posix.re({|([0-9]+)\.([0-9]+)\.([0-9]+)|}));
 
-let compare = (a, b) => {
-  switch (a, b) {
-  | (a, b) when a.major == b.major && a.minor == b.minor && a.point == b.point => 0
-  | (a, b) when a.major < b.major => (-1)
-  | (a, b) when a.major == b.major && a.minor < b.minor => (-1)
-  | (a, b) when a.major == b.major && a.minor == b.minor && a.point < b.point => (-1)
-  | _ => 1
-  };
+let required_direnv_version = {
+  major: 2,
+  minor: 21,
+  point: 3
 };
 
-let extract_version_number = cmd => {
-  switch (Util.run_process(cmd, ["--version"])) {
-  | (Ok (), stdout) when String.length(stdout) > 0 =>
-    switch (Re.exec(semver_re, stdout)) {
-    | exception Stdlib.Not_found =>
-      Error(
-        Printf.sprintf(
-          "Stdout did not contain a version number for `%s --version`",
-          cmd,
-        ),
-      )
-    | substrings =>
+let required_nix_version = {
+  major: 2,
+  minor: 10,
+  point: 0
+};
+
+// TODO: test this
+let compare_version_number = (a, b) => {
+  switch (a, b) {
+  | (a, b) when a.major == b.major && a.minor == b.minor && a.point == b.point => 0
+  | (a, b) when a.major < b.major => -1
+  | (a, b) when a.major == b.major && a.minor < b.minor => -1
+  | (a, b) when a.major == b.major && a.minor == b.minor && a.point < b.point => -1
+  | _ => 1
+  }
+}
+
+let%test_unit "compare_version_number" = [%test_eq: int](compare_version_number({major: 1, minor: 0, point: 0}, {major: 2, minor: 0, point: 0}), -1);
+
+let extract_version_number = (cmd) => {
+  let full_cmd = cmd ++ " --version";
+  switch (Core_unix.open_process_in(full_cmd) |> In_channel.input_line) {
+  | Some(stdout) => {
+      let substrings = Re.exec(semver_re, stdout);
       let groups = Re.Group.all(substrings);
       Ok({
         major: groups[1] |> int_of_string,
         minor: groups[2] |> int_of_string,
-        point: groups[3] |> int_of_string,
-      });
+        point: groups[3] |> int_of_string
+      })
     }
-  | _ => Error(Printf.sprintf("Failed executing '%s'", cmd))
-  };
+  | None => Error(Printf.sprintf("Failed executing '%s'\n", cmd))
+  }
 };
 
-let is_new_enough = (cur, needed) => {
+let is_version_new_enough = (cur, needed) => {
   switch (cur) {
-  | Ok(cur) =>
-    switch (compare(cur, needed)) {
-    | x when x < 0 => Ok(false)
-    | _ => Ok(true)
-    }
-  | Error(e) => Error(e)
-  };
-};
-
-let in_direnv = () =>
-  switch (Sys.getenv("direnv")) {
-  | Some(_) => true
-  | None => false
-  };
+    | Ok(cur) => {
+        switch (compare_version_number(cur, needed)) {
+        | x when x < 0 => Ok(false)
+        | _ => Ok(true)
+        }
+      }
+    | Error(e) => Error(e)
+  }
+}
 
 let preflight_versions = () => {
-  let is_nix_new_enough =
-    is_new_enough(extract_version_number("nix"), required_nix_version);
-  let is_direnv_new_enough =
-    is_new_enough(extract_version_number("direnv"), required_direnv_version);
-
-  switch (in_direnv(), is_direnv_new_enough, is_nix_new_enough) {
-  | (false, _, _) => Error("Not in direnv!")
-  | (_, Ok(false), _) => Error("Direnv version is not new enough")
-  | (_, _, Ok(false)) => Error("Nix version is not new enough")
-  | (_, Error(e), _) => Error(e)
-  | (_, _, Error(e)) => Error(e)
-  | (true, Ok(true), Ok(true)) => Ok()
+  let in_direnv = switch (Sys.getenv("direnv")) {
+    | Some(_) => true
+    | None => false
   };
+
+  let is_nix_new_enough = is_version_new_enough(extract_version_number("nix"), required_nix_version);
+  let is_direnv_new_enough = is_version_new_enough(extract_version_number("direnv"), required_direnv_version);
+
+  switch (in_direnv, is_direnv_new_enough, is_nix_new_enough) {
+    | (false, _, _) => Error("Not in direnv!")
+    | (_, Ok(false), _) => Error("Direnv version is not new enough")
+    | (_, _, Ok(false)) => Error("Nix version is not new enough")
+    | (_, Error(e), _) => Error(e)
+    | (_, _, Error(e)) => Error(e)
+    | (true, Ok(true), Ok(true)) => Ok()
+  }
 };
diff --git a/lib/flake_env__watches.re b/lib/flake_env__watches.re
index 5f0ee3e..db4cfc7 100644
--- a/lib/flake_env__watches.re
+++ b/lib/flake_env__watches.re
@@ -9,52 +9,40 @@ module Util = Flake_env__util;
 type watch = {
   exists: bool,
   modtime: int,
-  path: string,
+  path: string
 };
 
 [@deriving yojson]
-type watches = array(watch);
+type watches = array<watch>;
 
 let get = () => {
-  let direnv_watch_str =
-    Sys.getenv("DIRENV_WATCHES")
-    |> Option.value_exn(~message="Environment missing DIRENV_WATCHES");
-  let proc_info =
-    Unix.create_process(
-      ~prog="direnv",
-      ~args=["show_dump", direnv_watch_str],
-    );
+  let direnv_watch_str = Sys.getenv("DIRENV_WATCHES") |> Option.value_exn(~message="Environment missing DIRENV_WATCHES");
+  let proc_info = Unix.create_process(~prog="direnv", ~args=["show_dump", direnv_watch_str]);
   let sub_stdout = Unix.in_channel_of_descr(proc_info.stdout);
 
   switch (Unix.waitpid(proc_info.pid)) {
-  | Ok () => Ok(watches_of_yojson(Yojson.Safe.from_channel(sub_stdout)))
-  | _ => Error("Failed to parse watches")
-  };
+    | Ok() => Ok(watches_of_yojson(Yojson.Safe.from_channel(sub_stdout)))
+    | _ => Error("Failed to parse watches")
+  }
 };
 
-let get_path = doc =>
-  String.drop_prefix(doc |> member("path") |> to_string, 11);
+let get_path = (doc) => String.drop_prefix(doc |> member("path") |> to_string, 11);
 
 let rec get_paths_from_doc = (doc, paths) => {
   let p = get_path(doc);
-  let sub_paths =
-    List.concat(
-      doc
-      |> member("inputs")
-      |> to_assoc
-      |> List.map(~f=((_k, v)) => get_paths_from_doc(v, paths)),
-    );
-  List.concat([[p], sub_paths]);
+  let sub_paths = List.concat(
+    doc |> member("inputs")
+        |> to_assoc
+        |> List.map(~f=((_k, v)) => get_paths_from_doc(v, paths)));
+  List.concat([[p], sub_paths])
 };
 
 let get_input_paths = () => {
   switch (Util.nix(["flake", "archive", "--json", "--no-write-lock-file"])) {
-  | (Ok (), output) =>
-    get_paths_from_doc(Yojson.Safe.from_string(output), [])
-  | (Error(_), _) =>
-    Printf.eprintf(
-      "Failed to parse output of `nix flake archive --json`. Ignorning flake inputs. \n",
-    );
-    [];
-  };
+  | (Ok(), output) => get_paths_from_doc(Yojson.Safe.from_string(output), [])
+  | (Error(_), _) => {
+      Printf.eprintf("Failed to parse output of `nix flake archive --json`. Ignorning flake inputs. \n");
+      []
+    }
+  }
 };
diff --git a/lib/lib.re b/lib/lib.re
index e411503..1198207 100644
--- a/lib/lib.re
+++ b/lib/lib.re
@@ -1,96 +1,3 @@
-open Core;
-module Unix = Core_unix;
-
 module Util = Flake_env__util;
 module Watches = Flake_env__watches;
 module Versions = Flake_env__versions;
-
-let print_cur_cache = profile_rc => {
-  In_channel.read_all(profile_rc) |> Printf.printf("%s");
-};
-
-let clean_old_gcroots = layout_dir => {
-  Util.rmrf(layout_dir ++ "/flake-inputs/");
-  Util.rmrf(layout_dir);
-  Unix.mkdir_p(layout_dir ++ "/flake-inputs/");
-};
-
-let add_gcroot = (store_path, symlink) => {
-  switch (Util.nix(["build", "--out-link", symlink, store_path])) {
-  | (Ok (), _) => Ok()
-  | (err, _) => err
-  };
-};
-
-let freshen_cache = (layout_dir, hash, flake_specifier, other_args) => {
-  clean_old_gcroots(layout_dir);
-  let tmp_profile =
-    layout_dir
-    ++ "flake-tmp-profile."
-    ++ Core.Pid.to_string(Core_unix.getpid());
-
-  let pde_args = [
-    "print-dev-env",
-    "--profile",
-    tmp_profile,
-    flake_specifier,
-    ...other_args,
-  ];
-  let (exit_code, stdout_content) = Util.nix(pde_args);
-
-  let profile = layout_dir ++ "/flake-profile-" ++ hash;
-  let profile_rc = profile ++ ".rc";
-
-  switch (exit_code) {
-  | Ok () =>
-    Out_channel.with_file(
-      ~f=f => Out_channel.output_string(f, stdout_content),
-      profile_rc,
-    );
-    switch (add_gcroot(tmp_profile, profile)) {
-    | Ok () =>
-      Sys_unix.remove(tmp_profile);
-      let flake_input_cache_path = layout_dir ++ "/flake-inputs/";
-      let flake_inputs = Watches.get_input_paths();
-      flake_inputs
-      |> List.iter(~f=inpt => {
-           switch (
-             add_gcroot("/nix/store/" ++ inpt, flake_input_cache_path ++ inpt)
-           ) {
-           | Ok () => ()
-           | err =>
-             Printf.eprintf(
-               "Failed creating flake-input gcroot: %s\n",
-               Core_unix.Exit_or_signal.to_string_hum(err),
-             )
-           }
-         });
-      print_cur_cache(profile_rc);
-    | err =>
-      Printf.eprintf(
-        "Failed creating gcroot: %s\n",
-        Core_unix.Exit_or_signal.to_string_hum(err),
-      );
-      exit(1);
-    };
-  | err =>
-    Printf.eprintf(
-      "Failed evaluating flake: %s\n",
-      Core_unix.Exit_or_signal.to_string_hum(err),
-    );
-    exit(1);
-  };
-};
-
-let preflight = layout_directory => {
-  switch (
-    Versions.preflight_versions(),
-    Sys_unix.is_directory(layout_directory),
-  ) {
-  | (Ok(_), `Yes) => Ok()
-  | (Ok(_), _) =>
-    Unix.mkdir_p(layout_directory);
-    Ok();
-  | (err, _) => err
-  };
-};
diff --git a/tests/dune b/tests/dune
deleted file mode 100644
index dce3e4c..0000000
--- a/tests/dune
+++ /dev/null
@@ -1,10 +0,0 @@
-(tests
- (names flake_env_test_versions flake_env_test_watches flake_env_test_util)
- (deps spit_version.sh spit_gibberish.sh)
- (libraries
-  lib
-  alcotest
-  core
-  core_unix
-  core_unix.sys_unix
-  core_unix.filename_unix))
diff --git a/tests/flake_env_test_util.re b/tests/flake_env_test_util.re
deleted file mode 100644
index 9444d8a..0000000
--- a/tests/flake_env_test_util.re
+++ /dev/null
@@ -1,182 +0,0 @@
-open Core;
-module Unix = Core_unix;
-
-open Lib.Util;
-
-let _pp_exit_or_signal = (pp_fmt, e) =>
-  Fmt.pf(pp_fmt, "%s", Unix.Exit_or_signal.to_string_hum(e));
-let _exit_or_signal_eq = (a, b) => Unix.Exit_or_signal.compare(a, b) == 0;
-let testable_exit_or_signal =
-  Alcotest.testable(_pp_exit_or_signal, _exit_or_signal_eq);
-
-let _syst_to_bool =
-  fun
-  | `Yes => true
-  | _ => false;
-
-let check_exit_or_signal =
-  Alcotest.(check(Alcotest.pair(testable_exit_or_signal, string)));
-let testable_result_string =
-  Alcotest.testable(
-    (pp_fmt, elem) => {
-      switch (elem) {
-      | Ok(s) => Fmt.pf(pp_fmt, "Ok(%s)", s)
-      | Error(s) => Fmt.pf(pp_fmt, "Error(%s)", s)
-      }
-    },
-    (a, b) =>
-      switch (a, b) {
-      | (Ok(a), Ok(b)) => String.compare(a, b) == 0
-      | (Error(a), Error(b)) => String.compare(a, b) == 0
-      | _ => false
-      },
-  );
-let check_result_string = Alcotest.(check(testable_result_string));
-let check_bool = Alcotest.(check(bool));
-let check_get_args =
-  Alcotest.(
-    check(
-      Alcotest.result(Alcotest.triple(string, string, list(string)), unit),
-    )
-  );
-
-let test_run_process_success = () =>
-  check_exit_or_signal(
-    "Returns expected",
-    (Ok(), ""),
-    run_process("true", []),
-  );
-
-let test_run_process_failure = () =>
-  check_exit_or_signal(
-    "Returns expected",
-    (Error(`Exit_non_zero(1)), ""),
-    run_process("false", []),
-  );
-
-let test_run_process_stdout = () =>
-  check_exit_or_signal(
-    "Returns expected",
-    (Ok(), "echoed\n"),
-    run_process("echo", ["echoed"]),
-  );
-
-let test_hash_one = () => {
-  check_result_string(
-    "Hash matches",
-    Ok("32b4ac64be805d730745f6bac45a5d95174ebd10"),
-    hash_files([|"spit_version.sh"|]),
-  );
-};
-
-let test_hash_multiple = () => {
-  check_result_string(
-    "Hash matches",
-    Ok("e4c880fc6ab9a1b88e6be18e53fc4cec9f463d1a"),
-    hash_files([|"spit_version.sh", "spit_version.sh"|]),
-  );
-};
-
-let test_hash_filters_nonexistent = () => {
-  check_result_string(
-    "Hash matches",
-    Ok("32b4ac64be805d730745f6bac45a5d95174ebd10"),
-    hash_files([|"spit_version.sh", "FOOBARBAZ"|]),
-  );
-};
-
-let test_rmrf_file = () => {
-  let tmp_file_name = Filename_unix.temp_file("test", "txt");
-  rmrf(tmp_file_name);
-
-  check_bool(
-    "File removed",
-    false,
-    _syst_to_bool(Sys_unix.is_file(tmp_file_name)),
-  );
-};
-
-let test_rmrf_dir = () => {
-  let temp_dir_name = Filename_unix.temp_dir("test", "d");
-  let _ = Filename_unix.temp_file(~in_dir=temp_dir_name, "test", "txt");
-
-  rmrf(temp_dir_name);
-
-  check_bool(
-    "File removed",
-    false,
-    _syst_to_bool(Sys_unix.file_exists(temp_dir_name)),
-  );
-};
-
-let test_get_args_simple = () => {
-  check_get_args(
-    "Parses successfully",
-    Ok(("foo", "bar", ["oof", "rab", "zab"])),
-    get_args([|"000", "foo", "bar", "oof", "rab", "zab"|]),
-  );
-};
-
-let test_get_args_just_enough = () => {
-  check_get_args(
-    "Parses just enough args",
-    Ok(("foo", "bar", [])),
-    get_args([|"000", "foo", "bar"|]),
-  );
-};
-
-let test_get_args_error = () => {
-  check_get_args(
-    "Errors on too few args",
-    Error(),
-    get_args([|"000", "111"|]),
-  );
-};
-
-let () =
-  Alcotest.(
-    run(
-      "Watches",
-      [
-        (
-          "run_process",
-          [
-            test_case("Capture's Stdout", `Quick, test_run_process_stdout),
-            test_case("Success", `Quick, test_run_process_success),
-            test_case("Failure", `Quick, test_run_process_failure),
-          ],
-        ),
-        (
-          "hash_files",
-          [
-            test_case("Hashes one file", `Quick, test_hash_one),
-            test_case("Hashes multiple files", `Quick, test_hash_multiple),
-            test_case(
-              "Filters non-existent",
-              `Quick,
-              test_hash_filters_nonexistent,
-            ),
-          ],
-        ),
-        (
-          "rmrf helper",
-          [
-            test_case("Removes file", `Quick, test_rmrf_file),
-            test_case("Removes dir", `Quick, test_rmrf_dir),
-          ],
-        ),
-        (
-          "get_args",
-          [
-            test_case("Parses Args", `Quick, test_get_args_simple),
-            test_case(
-              "Parses just enough args",
-              `Quick,
-              test_get_args_just_enough,
-            ),
-            test_case("Handles too few args", `Quick, test_get_args_error),
-          ],
-        ),
-      ],
-    )
-  );
diff --git a/tests/flake_env_test_versions.re b/tests/flake_env_test_versions.re
deleted file mode 100644
index b0f7208..0000000
--- a/tests/flake_env_test_versions.re
+++ /dev/null
@@ -1,203 +0,0 @@
-open Lib;
-
-let pprint = (pp_fmt, version) => {
-  Versions.(
-    Fmt.pf(
-      pp_fmt,
-      "{ major: %d, minor: %d, point: %d }",
-      version.major,
-      version.minor,
-      version.point,
-    )
-  );
-};
-let testable_version =
-  Alcotest.testable(pprint, (a, b) => Versions.compare(a, b) == 0);
-
-let check_version =
-  Alcotest.(check(Alcotest.result(testable_version, string)));
-
-let test_compare_equal = () => {
-  let a = Versions.init(1, 0, 0);
-  Alcotest.(check(int))("equal", 0, Versions.compare(a, a));
-};
-
-let test_compare_first_major_greater = () => {
-  let a = Versions.init(2, 0, 0);
-  let b = Versions.init(1, 0, 0);
-  Alcotest.(check(int))("First major greater", 1, Versions.compare(a, b));
-};
-
-let test_compare_first_minor_greater = () => {
-  let a = Versions.init(1, 1, 0);
-  let b = Versions.init(1, 0, 0);
-  Alcotest.(check(int))("First minor greater", 1, Versions.compare(a, b));
-};
-
-let test_compare_first_point_greater = () => {
-  let a = Versions.init(1, 0, 1);
-  let b = Versions.init(1, 0, 0);
-  Alcotest.(check(int))("First point greater", 1, Versions.compare(a, b));
-};
-
-let test_compare_second_major_greater = () => {
-  let a = Versions.init(1, 0, 0);
-  let b = Versions.init(2, 0, 0);
-  Alcotest.(check(int))("Second major greater", -1, Versions.compare(a, b));
-};
-
-let test_compare_second_minor_greater = () => {
-  let a = Versions.init(1, 0, 0);
-  let b = Versions.init(1, 1, 0);
-  Alcotest.(check(int))("Second minor greater", -1, Versions.compare(a, b));
-};
-
-let test_compare_second_point_greater = () => {
-  let a = Versions.init(1, 0, 0);
-  let b = Versions.init(1, 0, 1);
-  Alcotest.(check(int))("Second point greater", -1, Versions.compare(a, b));
-};
-
-let test_ine_cur_newer = () => {
-  let a = Ok(Versions.init(2, 0, 0));
-  let b = Versions.init(1, 0, 0);
-  let ine = Versions.is_new_enough(a, b);
-  Alcotest.(check(bool))("Curr newer", true, ine |> Result.get_ok);
-};
-
-let test_ine_cur_older = () => {
-  let a = Ok(Versions.init(1, 0, 0));
-  let b = Versions.init(2, 0, 0);
-  let ine = Versions.is_new_enough(a, b);
-  Alcotest.(check(bool))("Curr older", false, ine |> Result.get_ok);
-};
-
-let test_ine_cur_equal = () => {
-  let a = Versions.init(1, 0, 0);
-  let ine = Versions.is_new_enough(Ok(a), a);
-  Alcotest.(check(bool))("Curr equal", true, ine |> Result.get_ok);
-};
-
-let test_ine_error = () => {
-  let a = Error("foobarbaz");
-  let ine = Versions.is_new_enough(a, Versions.init(1, 0, 0));
-  Alcotest.(check(Alcotest.result(bool, string)))(
-    "Error bubbled",
-    Error("foobarbaz"),
-    ine,
-  );
-};
-
-let test_in_direnv_true = () => {
-  Core_unix.putenv(~key="direnv", ~data="direnv");
-  Alcotest.(check(bool))("In direnv", true, Versions.in_direnv());
-};
-
-let test_in_direnv_false = () => {
-  Core_unix.unsetenv("direnv");
-  Alcotest.(check(bool))("Not in direnv", false, Versions.in_direnv());
-};
-
-let test_extract_version_number_success = () => {
-  let result = Versions.extract_version_number("../tests/spit_version.sh");
-  check_version("Versions", Ok(Versions.init(1, 1, 1)), result);
-};
-
-let test_extract_version_number_no_version = () => {
-  let result = Versions.extract_version_number("../tests/spit_gibberish.sh");
-  check_version(
-    "Versions",
-    Error(
-      "Stdout did not contain a version number for `../tests/spit_gibberish.sh --version`",
-    ),
-    result,
-  );
-};
-
-let test_extract_version_number_nonexistent = () => {
-  let result = Versions.extract_version_number("nonexistent.sh");
-  check_version(
-    "Versions",
-    Error("Failed executing 'nonexistent.sh'"),
-    result,
-  );
-};
-
-// TODO: Test:
-// * preflight_versions? impure, but m
-let () =
-  Alcotest.(
-    run(
-      "Versions",
-      [
-        (
-          "compare",
-          [
-            test_case("Versions Equal", `Quick, test_compare_equal),
-            test_case(
-              "First Major Greater",
-              `Quick,
-              test_compare_first_major_greater,
-            ),
-            test_case(
-              "First Minor Greater",
-              `Quick,
-              test_compare_first_minor_greater,
-            ),
-            test_case(
-              "First Point Greater",
-              `Quick,
-              test_compare_first_point_greater,
-            ),
-            test_case(
-              "Second Major Greater",
-              `Quick,
-              test_compare_second_major_greater,
-            ),
-            test_case(
-              "Second Minor Greater",
-              `Quick,
-              test_compare_second_minor_greater,
-            ),
-            test_case(
-              "Second Point Greater",
-              `Quick,
-              test_compare_second_point_greater,
-            ),
-          ],
-        ),
-        (
-          "is_new_enough",
-          [
-            test_case("Curr Newer", `Quick, test_ine_cur_newer),
-            test_case("Curr Older", `Quick, test_ine_cur_older),
-            test_case("Curr Equal", `Quick, test_ine_cur_equal),
-            test_case("Error", `Quick, test_ine_error),
-          ],
-        ),
-        (
-          "in_direnv",
-          [
-            test_case("true", `Quick, test_in_direnv_true),
-            test_case("false", `Quick, test_in_direnv_false),
-          ],
-        ),
-        (
-          "extract_version_number",
-          [
-            test_case("success", `Quick, test_extract_version_number_success),
-            test_case(
-              "no version number",
-              `Quick,
-              test_extract_version_number_no_version,
-            ),
-            test_case(
-              "missing binary",
-              `Quick,
-              test_extract_version_number_nonexistent,
-            ),
-          ],
-        ),
-      ],
-    )
-  );
diff --git a/tests/flake_env_test_watches.re b/tests/flake_env_test_watches.re
deleted file mode 100644
index 0a60efb..0000000
--- a/tests/flake_env_test_watches.re
+++ /dev/null
@@ -1,60 +0,0 @@
-open Lib.Watches;
-
-let test_get_path_removes_prefix = () => {
-  let input = `Assoc([("path", `String("aaaaaaaaaaabbbbb"))]);
-  Alcotest.(check(string))("Prefix removed", "bbbbb", get_path(input));
-};
-
-let test_get_paths_from_doc = () => {
-  let input =
-    `Assoc([
-      ("path", `String("aaaaaaaaaaabbbbb")),
-      (
-        "inputs",
-        `Assoc([
-          (
-            "foo",
-            `Assoc([
-              ("path", `String("aaaaaaaaaaaccccc")),
-              (
-                "inputs",
-                `Assoc([
-                  (
-                    "bar",
-                    `Assoc([
-                      ("path", `String("aaaaaaaaaaaddddd")),
-                      ("inputs", `Assoc([])),
-                    ]),
-                  ),
-                ]),
-              ),
-            ]),
-          ),
-        ]),
-      ),
-    ]);
-  Alcotest.(check(list(string)))(
-    "Gathers all inputs",
-    ["bbbbb", "ccccc", "ddddd"],
-    get_paths_from_doc(input, []),
-  );
-};
-
-let () =
-  Alcotest.(
-    run(
-      "Watches",
-      [
-        (
-          "get_path",
-          [
-            test_case("Removes prefix", `Quick, test_get_path_removes_prefix),
-          ],
-        ),
-        (
-          "get_paths_from_doc",
-          [test_case("Collects all paths", `Quick, test_get_paths_from_doc)],
-        ),
-      ],
-    )
-  );
diff --git a/tests/spit_gibberish.sh b/tests/spit_gibberish.sh
deleted file mode 100755
index e767e00..0000000
--- a/tests/spit_gibberish.sh
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/usr/bin/env sh
-
-echo "sdlfkjdsfweiojlsjslfj.dofiwoksdj/sfowiefjw0";
diff --git a/tests/spit_version.sh b/tests/spit_version.sh
deleted file mode 100755
index b8e3877..0000000
--- a/tests/spit_version.sh
+++ /dev/null
@@ -1,2 +0,0 @@
-#!/usr/bin/env bash
-echo "1.1.1";