change working directory

Did you know installables are parsed with regex? This mitigates how
horrifying that is.

bin/nix-build-and-cache

@@ -2,8 +2,6 @@
 
 set -euo pipefail
 
-toplevel="$(git rev-parse --show-toplevel)"
-
 # Build and cache the specified arguments
 just() {
     if command -v nom &> /dev/null; then
@@ -17,7 +15,7 @@ just() {
         return
     fi
 
-    nix run --inputs-from "$toplevel" attic -- \
+    nix run --inputs-from . attic -- \
         login \
         "$ATTIC_SERVER" \
         "$ATTIC_ENDPOINT" \
@@ -38,7 +36,7 @@ just() {
     # store paths include a newline in them.
     (
         IFS=$'\n'
-        nix shell --inputs-from "$toplevel" attic -c xargs \
+        nix shell --inputs-from . attic -c xargs \
             attic push "$ATTIC_SERVER:$ATTIC_CACHE" <<< "${cache[*]}"
     )
 }
@@ -46,10 +44,10 @@ just() {
 # Build and cache things needed for CI
 ci() {
     cache=(
-        --inputs-from "$toplevel"
+        --inputs-from .
 
         # Keep sorted
-        "$toplevel#devShells.x86_64-linux.default"
+        ".#devShells.x86_64-linux.default"
         attic#default
         nixpkgs#direnv
         nixpkgs#jq
@@ -63,12 +61,14 @@ ci() {
 packages() {
     readarray -t cache < <(
         nix flake show --json 2> /dev/null |
-            nix run --inputs-from "$toplevel" nixpkgs#jq -- \
+            nix run --inputs-from . nixpkgs#jq -- \
             -r \
-            '.packages."x86_64-linux" | keys | map("'"$toplevel"'#" + .) | .[]'
+            '.packages."x86_64-linux" | keys | map(".#" + .) | .[]'
     )
 
     just "${cache[@]}"
 }
 
+pushd "$(git rev-parse --show-toplevel)" > /dev/null
 "$@"
+popd > /dev/null