reverse build depends on stretch

[Brian May <brian@linuxpenguins.xyz>]

How do I do this? I am getting defeated at every step:

root@740eafbd9794:/build# grep-dctrl -s Package -F Build-Depends,Build-Depends-Indep quilt /var/lib/apt/lists/*Sources
grep-dctrl: /var/lib/apt/lists/*Sources: No such file or directory

root@740eafbd9794:/build# ls -l /var/lib/apt/lists/
total 83120
-rw-r----- 1 root root        0 Dec  2 21:40 lock
drwx------ 2 _apt root     4096 Dec  2 21:45 partial
-rw-r--r-- 1 root root 15040156 Jul 18 10:40 proxy.pri:9999_debian_dists_stretch_main_binary-amd64_Packages.lz4
-rw-r--r-- 1 root root 54488073 Jul 18 10:42 proxy.pri:9999_debian_dists_stretch_main_Contents-amd64.lz4
-rw-r--r-- 1 root root 14139930 Jul 18 10:40 proxy.pri:9999_debian_dists_stretch_main_source_Sources.lz4
-rw-r--r-- 1 root root   117947 Jul 18 10:52 proxy.pri:9999_debian_dists_stretch_Release
-rw-r--r-- 1 root root     2410 Jul 18 11:00 proxy.pri:9999_debian_dists_stretch_Release.gpg
-rw-r--r-- 1 root root    53018 Dec  2 10:51 proxy.pri:9999_security_dists_stretch_updates_InRelease
-rw-r--r-- 1 root root  1260511 Dec  2 10:51 proxy.pri:9999_security_dists_stretch_updates_main_binary-amd64_Packages.lz4

root@740eafbd9794:/build# file  /var/lib/apt/lists/*Sources.lz4 
/var/lib/apt/lists/proxy.pri:9999_debian_dists_stretch_main_source_Sources.lz4:
LZ4 compressed data (v1.4+)

root@740eafbd9794:/build# lzcat  /var/lib/apt/lists/*Sources.lz4 
lzcat:
/var/lib/apt/lists/proxy.pri:9999_debian_dists_stretch_main_source_Sources.lz4:
File format not recognized

root@740eafbd9794:/build# grep-dctrl -s Package -F Build-Depends,Build-Depends-Indep quilt /var/lib/apt/lists/*Sources.lz4
grep-dctrl:
/var/lib/apt/lists/proxy.pri:9999_debian_dists_stretch_main_source_Sources.lz4:7:
expected a colon.

root@740eafbd9794:/build# grep-aptavail -s Package -F Build-Depends,Build-Depends-Indep quilt
[ no results ]
-- 
Brian May <brian@linuxpenguins.xyz>
https://linuxpenguins.xyz/brian/