diff --git a/_docs/060_alternates.md b/_docs/060_alternates.md
index 09c6aa6..1c91e0c 100644
--- a/_docs/060_alternates.md
+++ b/_docs/060_alternates.md
@@ -30,11 +30,15 @@ be omitted. Most attributes can be abbreviated as a single letter.
 | `template`, `t` | Valid when the value matches a supported template processor. See the [Templates](/docs/templates) section for more details.|
 | `user`, `u` | Valid if the value matches the current user. Current user is calculated by running <code>id&nbsp;&#8209;u&nbsp;&#8209;n</code>. |
 | `distro`, `d` | Valid if the value matches the distro. Distro is calculated by running <code>lsb_release&nbsp;&#8209;si</code>. |
-| `os`, `o` | Valid if the value matches the OS. OS is calculated by running <code>uname&nbsp;&#8209;s</code>. |
+| `os`, `o` | Valid if the value matches the OS. OS is calculated by running <code>uname&nbsp;&#8209;s</code>. <sup>*</sup> |
 | `class`, `c` | Valid if the value matches the local.class configuration. Class must be manually set using <code>yadm&nbsp;config&nbsp;local.class&nbsp;&lt;class&gt;</code>. |
 |`hostname`, `h`|Valid if the value matches the short hostname. Hostname is calculated by running `hostname`, and trimming off any domain.|
 |`default`|Valid when no other alternate is valid.|
 
+<sub><sup>*
+The OS for "Windows Subsystem for Linux" is reported as "WSL", even though uname identifies as "Linux".
+</sup></sub>
+
 You may use any number of conditions, in any order. An alternate will only be
 used if _ALL_ conditions are valid. For all files managed by yadm's repository
 or listed in `$HOME/.config/yadm/encrypt`, if they match this naming convention,
diff --git a/_docs/070_templates.md b/_docs/070_templates.md
index 655bc4b..7c13eb4 100644
--- a/_docs/070_templates.md
+++ b/_docs/070_templates.md
@@ -43,10 +43,14 @@ When template processors run, they will be provided the following set of data.
 | `yadm.class`       | `YADM_CLASS`    | Locally defined yadm class | <code>yadm&nbsp;config&nbsp;local.class</code> |
 | `yadm.distro`      | `YADM_DISTRO`   | Distribution               | <code>lsb_release&nbsp;&#8209;si</code>        |
 | `yadm.hostname`    | `YADM_HOSTNAME` | Hostname                   | `hostname` (without domain)                    |
-| `yadm.os`          | `YADM_OS`       | Operating system           | <code>uname&nbsp;&#8209;s</code>               |
+| `yadm.os`          | `YADM_OS`       | Operating system           | <code>uname&nbsp;&#8209;s</code> <sup>*</sup>  |
 | `yadm.user`        | `YADM_USER`     | Current user               | <code>id&nbsp;&#8209;u&nbsp;&#8209;n</code>    |
 | `yadm.source`      | `YADM_SOURCE`   | Template filename          | (fully qualified path)                         |
 
+<sub><sup>*
+The OS for "Windows Subsystem for Linux" is reported as "WSL", even though uname identifies as "Linux".
+</sup></sub>
+
 ## Supported template processors
 
 default