diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..5cacc85
--- /dev/null
+++ b/.gitattributes
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+# Line-ending policy lives here, not in each contributor's core.autocrlf.
+# `text=auto` canonicalizes every file git detects as text to LF *in the
+# repository*; working trees may still use CRLF on Windows if that's the
+# local preference.
+* text=auto
+
+# Binary fixtures. DBN captures are byte-compared in tests, so make their
+# exemption explicit rather than relying on git's NUL-byte heuristic.
+# (`binary` is shorthand for `-text -diff`.)
+*.dbn  binary
+*.dbz  binary
+*.zst  binary
+*.frag binary