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+# Compile Example
+
+This folder uses modified `fr` files from [witnesscalc](https://github.com/0xPolygonID/witnesscalc). These files modify the Circom generated circutes to support compilation on ARM64. This involves adding a `fr_raw_arm64.s` and `fr_raw_generic` to implement the required `fr` operations. It also changes some types to signed/unsigned to match the ARM versions.
+
+Requires `gmp` and `nlohmann-json` to be installed and usable from `pkg-config`. On macos you can install them using: `brew install gmp nlohmann-json`.
+
+To build:
+
+```sh
+cd example/circom_build/
+nim cpp product.nim
+./product
+```