diff --git a/README.md b/README.md
index 1955cbcb..5cb307d3 100644
--- a/README.md
+++ b/README.md
@@ -91,6 +91,7 @@ Supported file systems
 * Amiga Fast File System, with international characters, directory cache and multi-user patches
 * Amiga Fast File System v2, untested
 * Acorn Advanced Disc Filing System
+* B-tree file system (btrfs)
 
 Supported checksums
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