diff --git a/stack.yaml b/stack.yaml
index 3cdc70c8b7bb744508c2e2e15fa076f799e240fa..7bf856dc34150fdc57a7bf1ea5410cac2cca4791 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -10,6 +10,9 @@ build:
         additional-args: [--hide-successes]
 
 extra-deps:
+- process-1.6.5.1
+- unix-2.7.2.2
+- directory-1.3.3.2
 - git: https://github.com/AshleyYakeley/haskell-src-exts.git
   commit: 31e1466e35cee9a91fa6678d73c938f0f44759eb
 - git: https://github.com/AshleyYakeley/hindent.git
diff --git a/stack.yaml.lock b/stack.yaml.lock
new file mode 100644
index 0000000000000000000000000000000000000000..dd249247ed0efacb0406469609da65a9a3ed20c9
--- /dev/null
+++ b/stack.yaml.lock
@@ -0,0 +1,61 @@
+# This file was autogenerated by Stack.
+# You should not edit this file by hand.
+# For more information, please see the documentation at:
+#   https://docs.haskellstack.org/en/stable/lock_files
+
+packages:
+- completed:
+    hackage: process-1.6.5.1@sha256:77a9afeb676357f67fe5cf1ad79aca0745fb6f7fb96b786d510af08f622643f6,2468
+    pantry-tree:
+      size: 1211
+      sha256: 19d944da6aa37944332e0726372288319852e5f72aa57dbc3516dc15e760a502
+  original:
+    hackage: process-1.6.5.1
+- completed:
+    hackage: unix-2.7.2.2@sha256:4ef1d010d70a4a07a717e853d4a440c105dad38c6199316e320fdd4c48dacd34,3495
+    pantry-tree:
+      size: 3536
+      sha256: 5b20b069022566dfd31f0061dc83cac8b4077725c6d780f097b4c35c7b6982f8
+  original:
+    hackage: unix-2.7.2.2
+- completed:
+    hackage: directory-1.3.3.2@sha256:79e15a62f90cb9f20f46b2b56fe67d00d71ed54cfad07ea337695f9ebb74baa4,2829
+    pantry-tree:
+      size: 3363
+      sha256: 07702ef1e423c4d3eb2e56f581c684e6a6956f40bf5a269bd41c758ccff7f493
+  original:
+    hackage: directory-1.3.3.2
+- completed:
+    cabal-file:
+      size: 4428
+      sha256: e9cd03672627da8e85225a8c855356df9ecaa7141e61b7d97860b511bfb6c7f0
+    name: haskell-src-exts
+    version: 1.21.1
+    git: https://github.com/AshleyYakeley/haskell-src-exts.git
+    pantry-tree:
+      size: 97010
+      sha256: 429025c159bccacbea490310ae69f5319ab524a845a07a5c3d51328b18fe4be8
+    commit: 31e1466e35cee9a91fa6678d73c938f0f44759eb
+  original:
+    git: https://github.com/AshleyYakeley/haskell-src-exts.git
+    commit: 31e1466e35cee9a91fa6678d73c938f0f44759eb
+- completed:
+    cabal-file:
+      size: 3609
+      sha256: f264293c32b704c623d98df85f873e322124e2c0058b9062798f891472f48ad4
+    name: hindent
+    version: 5.3.0
+    git: https://github.com/AshleyYakeley/hindent.git
+    pantry-tree:
+      size: 1906
+      sha256: 7221b71f7191814395b94522ed9d3599bb58cdfbf780a5a1196b27bc85ddd310
+    commit: d240eb7334cd08c7e377b59fcb1977bdf95527d6
+  original:
+    git: https://github.com/AshleyYakeley/hindent.git
+    commit: d240eb7334cd08c7e377b59fcb1977bdf95527d6
+snapshots:
+- completed:
+    size: 498186
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/13/22.yaml
+    sha256: d4f07dc3d5658260c2fe34266ad7618f6c84d34decf559c9c786ac1cfccf4e7b
+  original: lts-13.22