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+# BigIntArrayPackingStrategy
+
+Packs/unpacks arrays of 64-bit BigInt values.
+
+<!-- begin:auto-docs -->
+_(no submodules)_
+<!-- end:auto-docs -->
+
+## Schema tokens
+
+- `"bigint-i64[]"` — signed 64-bit BigInt array
+- `"bigint-u64[]"` — unsigned 64-bit BigInt array
+
+## Behaviour
+
+- Accepts `bigint[]`, `BigInt64Array`, or `BigUint64Array`.
+- Writes a 16-bit unsigned length prefix.
+- Each element is written as 8 bytes (big-endian).