3 files changed, 6 insertions, 1 deletions
diff --git a/safety.md b/safety.md
index 8a03652..b8a2303 100644
--- a/safety.md
+++ b/safety.md
@@ -1,5 +1,9 @@
 Each item in Wikipedia's [list of types of memory errors](https://en.wikipedia.org/wiki/Memory_safety#Types_of_memory_errors) and what Crowbar does to prevent them.
 
+In general, Crowbar does its best to ensure that code will not exhibit any of the following memory errors.
+However, sometimes the compiler knows less than the programmer, and so code that looks dangerous is actually fine.
+Crowbar allows programmers to suspend the memory safety checks with the `fragile` keyword.
+
 # Access errors
 
 ## Buffer overflow
diff --git a/syntax.md b/syntax.md
index 89c1c49..6413f8a 100644
--- a/syntax.md
+++ b/syntax.md
@@ -36,6 +36,7 @@ A *keyword* is one of the following literal words:
 - `extern`
 - `float`
 - `for`
+- `fragile`
 - `function`
 - `if`
 - `include`
diff --git a/vs-c.md b/vs-c.md
index bceaab1..b6cbcd5 100644
--- a/vs-c.md
+++ b/vs-c.md
@@ -45,7 +45,7 @@ Some type modifiers in C only apply in very specific circumstances and so aren't
 Some C features are footguns by default, so Crowbar ensures that they are only used correctly.
 
 -   Unions are not robust by default.
-    Crowbar only supports unions when they are [tagged unions](tagged-unions.md).
+    Crowbar only supports unions when they are [tagged unions](tagged-unions.md) (or declared and used with the `fragile` keyword).
 
 C's syntax isn't perfect, but it's usually pretty good.
 However, sometimes it just sucks, and in those cases Crowbar makes changes.