diff --git a/doc/next/5-toolchain.md b/doc/next/5-toolchain.md
index 0f4a816479..971fa39608 100644
--- a/doc/next/5-toolchain.md
+++ b/doc/next/5-toolchain.md
@@ -1,7 +1,15 @@
 ## Compiler {#compiler}
 
+<!-- https://go.dev/issue/26379 -->
+
+The compiler and linker in Go 1.25 now generate debug information
+using [DWARF version 5](https://dwarfstd.org/dwarf5std.html); the
+newer DWARF version reduces the space required for debuging
+information in Go binaries.
+DWARF 5 generation is gated by the "dwarf5" GOEXPERIMENT; this
+functionality can be disabled (for now) using GOEXPERIMENT=nodwarf5.
+
 ## Assembler {#assembler}
 
 ## Linker {#linker}
 
-