diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..e9c24e3
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,5 @@
+# Files whose SHA-256 is frozen in mappings/benchmark_reserve.json and checked by
+# tests/test_benchmark_reserve.py. Keep them LF on every platform so a Windows
+# checkout (core.autocrlf=true) doesn't change the bytes and fail the hash check.
+mappings/soulcap_entities.tsv  text eol=lf
+mappings/curated_mappings.tsv  text eol=lf