diff --git a/artiq/firmware/libc/Cargo.toml b/artiq/firmware/libc/Cargo.toml
new file mode 100644
index 000000000..7231c77c4
--- /dev/null
+++ b/artiq/firmware/libc/Cargo.toml
@@ -0,0 +1,5 @@
+[package]
+name = "libc"
+version = "0.1.0"
+authors = ["M-Labs"]
+edition = "2018"
diff --git a/artiq/firmware/libc/src/lib.rs b/artiq/firmware/libc/src/lib.rs
new file mode 100644
index 000000000..e5eb97a23
--- /dev/null
+++ b/artiq/firmware/libc/src/lib.rs
@@ -0,0 +1,8 @@
+// Helper crate for dealing with c ffi
+#![allow(non_camel_case_types)]
+#![no_std]
+pub type c_char = i8;
+pub type c_int = i32;
+pub type size_t = usize;
+pub type uintptr_t = usize;
+pub type c_void = core::ffi::c_void;