I've been using it to wrap nodejs package managers in response to all malware shipped through them over the past few years. A simple wrapper script like this works fine (symlinked to `npm`/`yarn`/`pnpm` into whatever directory is the first in $PATH):

  bin=$(basename "$0")

  exec bwrap \
    --bind "$PWD" "$PWD" \
    --dev /dev \
    --die-with-parent \
    --dir /tmp \
    --dir /var \
    --disable-userns \
    --new-session \
    --proc /proc \
    --ro-bind /etc/ca-certificates /etc/ca-certificates \
    --ro-bind /etc/resolv.conf /etc/resolv.conf \
    --ro-bind /etc/ssl /etc/ssl \
    --ro-bind /usr /usr \
    --setenv PATH /usr/bin \
    --share-net \
    --symlink /tmp /var/tmp \
    --symlink /usr/bin /bin \
    --symlink /usr/lib /lib \
    --symlink /usr/lib64 /lib64 \
    --unshare-all \
    --unshare-user \
    "/usr/bin/$bin" "$@"

It gets read-write access to the current path, and to its own copy of ~/.cache and ~/.local/share. It doesn't see anything else from your home directory, including any adjacent projects. It can easily be locked down further by allowing read-only access to the project, and read-write access to node_modules and nothing else.