The golang-github-mailgun-ttlmap package ships upstream code from 2017
and appears unmaintained.

https://tracker.debian.org/pkg/golang-github-mailgun-ttlmap

The upstream project was deprecated in 2017:

https://github.com/mailgun/ttlmap
   This repo is deprecated, Renamed to TTLMap and moved to
http://github.com/mailgun/holster

This package DO have one reverse dependency in Debian --
golang-github-vulcand-oxy -- however that package incorrectly
Build-Depends on golang-github-mailgun-ttlmap-dev, there is no mention
of 'ttlmap' in its go.mod.  That package is also not in testing due to a
FTBFS bug around two years ago:

https://tracker.debian.org/pkg/golang-github-vulcand-oxy

Removing golang-github-mailgun-ttlmap from the archive thus shouldn't
have any significant consequences, and if anyone is interested in
rescuing golang-github-vulcand-oxy they can drop the B-D.

This removal request is part of a larger batch to remove 100+ unused
golang-*-dev packages from Debian.  I believe the QA cost associated
with keeping all of them is larger than the cost of (hopefully extremely
rare) re-introduction of any accidentally removed package if there is
ever any future need for it.  Meanwhile, I don't think it is useful to
keep this package in Debian.

/Simon

jas@frallan:~/dpkg/golang-qa-find-zombies$ ssh mirror.ftp-master.debian.org dak rm -Rn golang-github-mailgun-ttlmap
Will remove the following packages from unstable:

golang-github-mailgun-ttlmap | 0.0~git20170619.c1c17f7-2 | source
golang-github-mailgun-ttlmap-dev | 0.0~git20170619.c1c17f7-2 | all

Maintainer: Debian Go Packaging Team <team+pkg-go@tracker.debian.org>
------------------- Reason -------------------

----------------------------------------------

Checking reverse dependencies...
# Broken Depends:
golang-github-vulcand-oxy: golang-github-vulcand-oxy-dev

# Broken Build-Depends:
golang-github-vulcand-oxy: golang-github-mailgun-ttlmap-dev

Dependency problem found.

jas@frallan:~/dpkg/golang-qa-find-zombies$ ssh mirror.ftp-master.debian.org dak rm -Rn golang-github-vulcand-oxy
Will remove the following packages from unstable:

golang-github-vulcand-oxy |    2.0.0-3 | source
golang-github-vulcand-oxy-dev |    2.0.0-3 | all

Maintainer: Debian Go Packaging Team <team+pkg-go@tracker.debian.org>

------------------- Reason -------------------

----------------------------------------------

Checking reverse dependencies...
No dependency problem found.

jas@frallan:~/dpkg/golang-qa-find-zombies$