diff --git a/bin/launch-client.md b/bin/launch-client.md
index d34e1d7f03888f100914c4c1b512b687423c78a7..e65333338cb69a8a95434768e0b42e5371265e75 100644
--- a/bin/launch-client.md
+++ b/bin/launch-client.md
@@ -78,8 +78,8 @@ This uses **$SHELL** if available in the container, falling back to
     that is running inside a Steam Linux Runtime container, so that
     the *COMMAND* is run outside the container in approximately the
     same execution environment as the script that launches the Steam client.
-    The Steam Runtime 1 'scout' and Steam Runtime 1½ 'heavy' library
-    stacks that are used to run major components of the Steam client will
+    The Steam Runtime 1 'scout' library stack that is
+    used to run major components of the Steam client will
     usually **not** be present in the **LD_LIBRARY_PATH** for commands
     run like this.
 
diff --git a/docs/distro-assumptions.md b/docs/distro-assumptions.md
index 924a38cafe436dc69cbce89adc75213667d79c9b..b6f4110e659692ef20743ca11644c06a4af87d00 100644
--- a/docs/distro-assumptions.md
+++ b/docs/distro-assumptions.md
@@ -26,16 +26,10 @@ Steam games:
 
 - The [traditional Steam Runtime][ldlp],
     implemented in terms of `LD_LIBRARY_PATH`.
-    Instances of this can be found in
-    `~/.steam/root/ubuntu12_32/steam-runtime` and
-    `~/.steam/root/ubuntu12_64/steam-runtime-heavy` in a working Steam
-    installation.
+    In a working Steam installation,
     `~/.steam/root/ubuntu12_32/steam-runtime` provides
     [Steam Runtime 1 'scout'][scout],
-    based on Ubuntu 12.04.
-    `~/.steam/root/ubuntu12_64/steam-runtime-heavy` provides
-    [Steam Runtime 1½ 'heavy'][heavy],
-    based on Debian 8.
+    based on Ubuntu 12.04, as a `LD_LIBRARY_PATH` runtime.
 
 - The [container runtime framework][container runtime],
     implemented in terms of containers launched by the pressure-vessel tool.
@@ -317,7 +311,7 @@ single `ld.so.cache`.
 The operating system should not edit the Steam Runtime in-place or
 attempt to disable it.
 
-For the `LD_LIBRARY_PATH`-based 'scout' and 'heavy' runtimes, the
+For the `LD_LIBRARY_PATH`-based 'scout' runtime, the
 operating system may provide shared libraries that are newer than
 the corresponding libraries in the Steam Runtime, backwards-compatible
 with the Steam Runtime libraries, and have the same `DT_SONAME` ELF header.
@@ -467,7 +461,7 @@ On entry to Steam code, the following environment variables should
 
 * `STEAM_RUNTIME` *(debug) (internal)*
 * `STEAM_RUNTIME_SCOUT` *(debug)*
-* `STEAM_RUNTIME_HEAVY` *(debug)*
+* `STEAM_RUNTIME_HEAVY` *(debug) (obsolete)*
 * `STEAM_RUNTIME_DEBUG` *(debug)*
 * `STEAM_RUNTIME_DEBUG_DIR` *(debug)*
 * `STEAM_RUNTIME_LIBRARY_PATH` *(internal)*
@@ -666,7 +660,6 @@ container runtime on a new distribution, in particular:
 [bubblewrap]: https://github.com/containers/bubblewrap
 [container runtime]: container-runtime.md
 [eudev]: https://github.com/eudev-project/eudev
-[heavy]: https://gitlab.steamos.cloud/steamrt/steamrt/-/blob/steamrt/heavy/README.md
 [ldlp]: ld-library-path-runtime.md
 [libcapsule]: https://gitlab.collabora.com/vivek/libcapsule
 [libudev0-shim]: https://github.com/archlinux/libudev0-shim
diff --git a/docs/ld-library-path-runtime.md b/docs/ld-library-path-runtime.md
index a199b99b5563c22f77be1144ebca77df9dc15945..b9ce9baf814f2b2f0288242ae950257bc0ed32db 100644
--- a/docs/ld-library-path-runtime.md
+++ b/docs/ld-library-path-runtime.md
@@ -101,15 +101,10 @@ recorded at FOSDEM 2020: [Containers and Steam][].
 
 ## The `heavy` runtime
 
-The `steamwebhelper` component that is used for the Steam user interface
-requires newer libraries than the ones available in `scout`.
-To avoid destabilizing `scout`, it has its own set of libraries,
+Historically, the `steamwebhelper` component that is used for the Steam
+user interface used a newer `LD_LIBRARY_PATH` runtime,
 referred to as Steam Runtime 1½ `heavy`.
-
-This behaves in the same way as the `scout` runtime, but it contains
-fewer libraries (only the ones that are needed for the `steamwebhelper`),
-and it is newer than `scout` (it's based on Debian 8 instead of
-Ubuntu 12.04).
+It is now obsolete and is no longer included in Steam.
 
 Documentation in the `steamrt` "metapackage" provides
 [more information about heavy][heavy].
diff --git a/pressure-vessel/CONTRIBUTING.md b/pressure-vessel/CONTRIBUTING.md
index 11e7bef3d945c07659430f527f981bd9daf6f9f3..4f6d68afa6f73517f6ad7c6f0f13aea11d3bd492 100644
--- a/pressure-vessel/CONTRIBUTING.md
+++ b/pressure-vessel/CONTRIBUTING.md
@@ -59,7 +59,3 @@ in scout, which are pretty old.
 
 The scout build environment has backports of Python 3.5 and Meson, so we
 can rely on those at build-time.
-
-If we gain a dependency on glibc 2.19 or other newer libraries, we'll have
-to increase the build environment to SteamRT 1½ 'heavy', and backport
-Python 3.5 and Meson to 'heavy'.
diff --git a/subprojects/container-runtime/README.md b/subprojects/container-runtime/README.md
index 6284f0886682a9e623addb470b7d1df866d7b13b..f5ab9646d149bc16882e95ee05a3592f4ce47880 100644
--- a/subprojects/container-runtime/README.md
+++ b/subprojects/container-runtime/README.md
@@ -15,7 +15,7 @@ How this fits into the overall Steam Runtime project
     <https://repo.steampowered.com/steamrt-images-scout/snapshots/latest-container-runtime-depot/sources/>.
     This is not part of this git repository.
 
-2. For `scout` and `heavy` only: Put together the .deb packages into the
+2. For `scout` only: Put together the .deb packages into the
     `LD_LIBRARY_PATH`-based Steam Runtime.
     This git repository is not relevant for this step.