diff --git a/debian/changelog b/debian/changelog
index 56d61ce..ceedc5c 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,11 @@
+slib (3b6-4) UNRELEASED; urgency=medium
+
+  * Update watch file format version to 4.
+  * Use secure URI in Homepage field.
+  * Update standards version to 4.5.1, no changes needed.
+
+ -- Debian Janitor <janitor@jelmer.uk>  Wed, 16 Jun 2021 07:58:08 -0000
+
 slib (3b6-3) unstable; urgency=low
 
   * debian/tests: exclude mit-scheme and chezscheme tests on platforms
diff --git a/debian/control b/debian/control
index 5e9cfdf..2d39171 100644
--- a/debian/control
+++ b/debian/control
@@ -4,8 +4,8 @@ Priority: optional
 Maintainer: Nick Gasson <nick@nickg.me.uk>
 Build-Depends: debhelper-compat (= 13), scm, texi2html, texinfo, mit-scheme,
  chezscheme, gambc
-Standards-Version: 4.5.0
-Homepage: http://people.csail.mit.edu/jaffer/SLIB.html
+Standards-Version: 4.5.1
+Homepage: https://people.csail.mit.edu/jaffer/SLIB.html
 Vcs-Browser: https://salsa.debian.org/nickg/slib
 Vcs-Git: https://salsa.debian.org/nickg/slib.git
 
diff --git a/debian/watch b/debian/watch
index 1793b22..54352da 100644
--- a/debian/watch
+++ b/debian/watch
@@ -1,2 +1,2 @@
-version=3
+version=4
 https://people.csail.mit.edu/jaffer/SLIB.html .*slib-([\d.]+.*)\.zip