diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..b259bac
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,158 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
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+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
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+]
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+ "futures-util",
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+ "futures-core",
+ "futures-io",
+ "futures-macro",
+ "futures-sink",
+ "futures-task",
+ "memchr",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
+[[package]]
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+ "futures",
+]
+
+[[package]]
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+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-xid",
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diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..03a5fc5
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "hrtb_test"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+futures = "0.3.21"
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..9308005
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,35 @@
+use futures::Future;
+trait TestFn<'a>: Send + Sync {
+    type Fut: Future<Output = ()>;
+    fn call(self, v: &'a i64) -> Self::Fut;
+}
+
+impl<'a, F, Fut> TestFn<'a> for F
+where
+    F: FnOnce(&'a i64) -> Fut + Send + Sync,
+    Fut: Future<Output = ()>,
+{
+    type Fut = Fut;
+
+    fn call(self, v: &'a i64) -> Self::Fut {
+        self(v)
+    }
+}
+
+async fn test<F>(func: F)
+where
+    F: for<'a> TestFn<'a>,
+{
+    func.call(&3).await
+}
+
+async fn main_async() {
+    test(|v| async move {
+        println!("works! {} ", v);
+    })
+    .await;
+}
+
+fn main() {
+    futures::executor::block_on(main_async());
+}