pdnsutil edit-zone requires EDITOR to be set. Currently there's no editor installed at all. Adding vim, so that it can be used as default editor by pdnsutil edit-zone.
# Reusable layer for base update - Should be cached from builder
RUN apt-get update && apt-get -y dist-upgrade && apt-get clean
-# Ensure python3 and jinja2 is present (for startup script), and sqlite3 (for db schema), and tini (for signal management)
-RUN apt-get install -y python3 python3-jinja2 sqlite3 tini libcap2-bin && apt-get clean
+# Ensure python3 and jinja2 is present (for startup script), and sqlite3 (for db schema), and tini (for signal management),
+# and vim (for pdnsutil edit-zone)
+RUN apt-get install -y python3 python3-jinja2 sqlite3 tini libcap2-bin vim && apt-get clean
# Output from builder
COPY --from=builder /build /