--- a/taskcluster/ci/config.yml
+++ b/taskcluster/ci/config.yml
@@ -36,16 +36,17 @@ treeherder:
         'BM-L10n': 'Beetmover for locales'
         'BMR-L10n': 'Beetmover repackages for locales'
         'c-Up': 'Balrog submission of complete updates'
         'cs': 'Checksum signing'
         'rs': 'Repackage signing'
         'BMcs': 'Beetmover checksums,'
         'Aries': 'Aries Device Image'
         'Deb7': 'Packages for Debian 7'
+        'Deb9': 'Packages for Debian 9'
         'Nexus 5-L': 'Nexus 5-L Device Image'
         'I': 'Docker Image Builds'
         'TL': 'Toolchain builds for Linux 64-bits'
         'TM': 'Toolchain builds for OSX'
         'TMW': 'Toolchain builds for Windows MinGW'
         'TW32': 'Toolchain builds for Windows 32-bits'
         'TW64': 'Toolchain builds for Windows 64-bits'
         'Searchfox': 'Searchfox builds'

--- a/taskcluster/ci/packages/kind.yml
+++ b/taskcluster/ci/packages/kind.yml
@@ -77,16 +77,32 @@ jobs:
         url: https://www.mercurial-scm.org/release/mercurial-4.4.2.tar.gz
         sha256: dc2f72caccd6b760226753d48c2f4e8889fe176a6b23ef50775caac55ce28b85
       pre-build-command: >-
         cp -r contrib/debian debian &&
         sed -i -e "s/__VERSION__/$(awk -F\" '$2 {print $2}' mercurial/__version__.py)-1.deb7moz1/" \
                -e "s/__DATE__/$(date --rfc-2822)/" \
                -e "s/__CODENAME__/wheezy/" debian/changelog
 
+  deb9-mercurial:
+    description: "Modern Mercurial for Debian stretch"
+    treeherder:
+      symbol: Deb9(hg)
+    run:
+      using: debian-package
+      dist: stretch
+      tarball:
+        url: https://www.mercurial-scm.org/release/mercurial-4.4.2.tar.gz
+        sha256: dc2f72caccd6b760226753d48c2f4e8889fe176a6b23ef50775caac55ce28b85
+      pre-build-command: >-
+        cp -r contrib/debian debian &&
+        sed -i -e "s/__VERSION__/$(awk -F\" '$2 {print $2}' mercurial/__version__.py)-1.deb9moz1/" \
+               -e "s/__DATE__/$(date --rfc-2822)/" \
+               -e "s/__CODENAME__/stretch/" debian/changelog
+
   deb7-git:
     description: "Modern git for Debian wheezy"
     treeherder:
       symbol: Deb7(git)
     run:
       using: debian-package
       dsc:
         url: http://snapshot.debian.org/archive/debian/20160317T100542Z/pool/main/g/git/git_2.8.0%7Erc3-1.dsc