diff --git a/README.md b/README.md
index e6a9f7a..bfcd1ab 100644
--- a/README.md
+++ b/README.md
@@ -34,6 +34,7 @@ Project or files:
 │   ├── err_derive
 │   └── quick_error
 ├── __ffi
+│   ├── c
 │   ├── c_export
 │   ├── c_layout
 │   ├── cpp
@@ -142,7 +143,7 @@ Project or files:
     ├── vec.rs
     └── while.rs
 
-114 directories, 26 files
+115 directories, 26 files
 
 ```
 
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new file mode 100644
index 0000000..52ad7a7
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diff --git a/__ffi/c/Cargo.toml b/__ffi/c/Cargo.toml
new file mode 100644
index 0000000..0f82653
--- /dev/null
+++ b/__ffi/c/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "c"
+version = "0.1.0"
+authors = ["Hatter Jiang <jht5945@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+inline-c = "0.1.3"
+
diff --git a/__ffi/c/src/main.rs b/__ffi/c/src/main.rs
new file mode 100644
index 0000000..11ba9e4
--- /dev/null
+++ b/__ffi/c/src/main.rs
@@ -0,0 +1,22 @@
+use inline_c::assert_c;
+
+fn main() {
+    println!("Hello, world!");
+}
+
+#[test]
+fn test_stdout() {
+    (assert_c! {
+        #include <stdio.h>
+
+        int main() {
+            printf("Hello, World!");
+
+            return 0;
+        }
+    })
+    .success()
+    .stdout("Hello, World!");
+}
+
+