diff --git a/justfile b/justfile
index c845134..8d57bba 100644
--- a/justfile
+++ b/justfile
@@ -248,10 +248,10 @@ rebase-commits commit=`cd "$invokedir"; just _a_commit`:
 
 [no-cd]
 _bump +$packages:
-    #!/usr/bin/env -S bash -euo pipefail
-    test -e .git
+    #!/usr/bin/env -S bash -euo pipefail -x
+    [[ -e .git && flake.nix ]]
     printf "%s.src\n" "$@" | xargs just _build_packages results-src-old ||: # TODO: unpack?
-    config=(
+    config=(env
         NIXPKGS_ALLOW_UNFREE=1
         NIXPKGS_ALLOW_BROKEN=1
         NIXPKGS_ALLOW_INSECURE=1
@@ -281,59 +281,72 @@ _bump +$packages:
     $GIT diff
     printf "delta results-src-{old,new}/%s/.\n" "$@"
 
-#fix package=`just _a_package`:
-
-# ./mk-fix.sh "{{package}}"
-@fix $package=`just _a_package`:
+@fix +packages:
+    [[ $# -gt 0 ]] || set -- $(just _some_packages); \
     cd "$(just _new_worktree fix "$(echo "$package" | rev | cut -d. -f1 | rev)")"; \
     just _fix "$package" && $SHELL
 
 [no-cd]
-_fix $package:
+_fix +packages:
     #!/usr/bin/env -S bash -euo pipefail
-    test -e .git
-    nix-build . -A "$package".src --out-link result-src
-    test -d $(readlink result-src) && {
-        mkdir -p result-src-writeable
-        rsync -rxL result-src/ result-src-writeable/
-        chmod -R +w result-src-writeable
-    } ||:
-    test -f $(readlink result-src) && {
-      mkdir result-src-writeable
-      atool $(readlink result-src) --extract-to=result-src-writeable
-      if test $(ls result-src-writeable | wc -l ) -eq 1 && test -d result-src-writeable/* ; then
-          mv result-src-writeable{,-old}
-          mv result-src-writeable-old/* result-src-writeable
-          rmdir result-src-writeable-old
-      fi
-    } ||:
-    test -d result-src-writeable && (
-        cd result-src-writeable
-        $GIT init
-        $GIT add .
-        $GIT commit -m "Base" >/dev/null
-    )
-    cat <<-"EOF" > build.nix
-        #!/usr/bin/env -S nom build -f
-        let pkgs = import ./. {}; in pkgs.{{ package }}.overrideAttrs { src = ./result-src-writeable; }
-    EOF
+    [[ -e .git && flake.nix ]]
+    local packages=("$@")
+    just _build_packages results-src "${packages[@]/%/.src}" ||:
+    # TODO: make this rutine reuseable?
+    mkdir -p result-src-writeable
+    for result in results-src/*; do;
+        result_writeable=result-src-writeable/$(basename "$result")
+        mkdir -p "$result_writeable"
+        if [[ -d $(readlink "$result") ]]; then
+            rsync -rxL "$result/" "$result_writeable/" &&
+            chmod -R +w "$result_writeable/" ||:
+        elif [[ -f $(readlink "$result") ]]; then
+            atool "$(readlink result-src)" --extract-to="$result_writeable/" ||:
+            if [[ $(ls "$result_writeable" | wc -l ) -eq 1 && test -d "$result_writeable"/* ]]; then
+                mv "$result_writeable"{,-old}
+                mv "$result_writeable"-old/* "$result_writeable"
+                rmdir "$result_writeable"-old
+            fi
+        fi
+        (
+            cd "$result_writeable"
+            $GIT init
+            $GIT add .
+            $GIT commit -m "Base" >/dev/null
+        ) ||:
+    done
+    printf >build.nix "#!/usr/bin/env -S nom build -f\n"
+    printf >build.nix "let pkgs = import ./. { }; in {\n%s\n}\n" "$(
+        for package in "${packages[@]}"; do
+            printf "  %s = pkgs.%s.overrideAttrs { src = ./result-src-writeable/%s-src; };" "$package" "$package" "$package"
+        done
+    )"
     chmod +x build.nix
-    NIXPKGS_ALLOW_UNFREE=1 just build-packages "$package" ||:
+    if command -v bat >/dev/null;
+    then bat build.nix
+    else cat build.nix
+    fi
+    NIXPKGS_ALLOW_UNFREE=1 just build-packages "${packages[@]}" ||:
     echo "# $package"
-    echo ' ./build.nix'
-    echo ' ./results/_rerun.sh'
+    echo " ./build.nix "${packages[*]/#/-A }"
+    echo " ./results/_rerun.sh"
 
 pr $number=`just _a_pr`:
     #!/usr/bin/env -S bash -euo pipefail
     number=$(just _sanitize_pr_url "$number")
-    if test -d prs/pr-"$number"-* ; then
-        cd prs/pr-"$number"-* && $SHELL
+    if [[ -d prs/pr-"$number" ]]; then
+        cd prs/pr-"$number"
+    elif test -d prs/pr-"$number"-*; then
+        cd prs/pr-"$number"-*
     else
-        cd "$(just _new_worktree prs pr-{{ number }} "upstream/master" "")"
-        gh pr checkout {{ number }}
-        $GIT branch -D prs-$(basename "$PWD")
-        $SHELL
+        (cd master;
+            $GIT worktree prune
+            $GIT worktree add ../prs/pr-"$number"
+        )
+        cd prs/pr-"$number"
+        gh pr checkout "$number"
     fi
+    $SHELL
 
 @pr-comment-diff:
     cd "$invokedir"; just _pr_post_diff comment
@@ -414,7 +427,7 @@ _mk_worktree $name $dir $base="upstream/master" $onto="":
     $GIT worktree add ../"$dir" "$name"
     cd ../"$dir"
     $GIT pull "$remote" "$branch"
-    test -z "$onto" || just rebase-onto HEAD "$onto"
+    just rebase-onto HEAD "$onto"
 
 pop-commits-to-new-worktree $commits=`cd "$invokedir"; just _some_commits`:
     #!/usr/bin/env -S bash -euo pipefail
@@ -565,7 +578,7 @@ _packages_json:
     gum spin --show-output just list-packages | cut -f1 | fzf --sync --layout=reverse --height 15 | grep .
 
 @_some_packages:
-    gum spin --show-output just list-packages | cut -f1 | fzf --sync --layout=reverse --multi | grep .
+    gum spin --show-output just list-packages | cut -f1 | fzf --sync --layout=reverse --height 15 --multi | grep .
 
 @_a_pr:
     cd master; gh pr list --limit 1000 --json 'number,title' --state open | jq '.[]|"\(.number) - \(.title)"' -r | gum filter --placeholder "Pick PR..." --height 10 | cut -d' ' -f1