diff --git a/README.md b/README.md
index e371950..087d7e5 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,8 @@ Project or files:
 ├── README_2.md
 ├── __bin
 │   └── goblin
+├── __compress
+│   └── zstd-demo
 ├── __concurrent
 │   ├── arc-swap
 │   ├── async_study
@@ -267,6 +269,6 @@ Project or files:
     ├── vec.rs
     └── while.rs
 
-236 directories, 39 files
+238 directories, 39 files
 ```
 
diff --git a/__compress/zstd-demo/Cargo.lock b/__compress/zstd-demo/Cargo.lock
new file mode 100644
index 0000000..79d7060
--- /dev/null
+++ b/__compress/zstd-demo/Cargo.lock
@@ -0,0 +1,70 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "cc"
+version = "1.0.79"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50d30906286121d95be3d479533b458f87493b30a4b5f79a607db8f5d11aa91f"
+dependencies = [
+ "jobserver",
+]
+
+[[package]]
+name = "jobserver"
+version = "0.1.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "068b1ee6743e4d11fb9c6a1e6064b3693a1b600e7f5f5988047d98b3dc9fb90b"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.139"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "201de327520df007757c1f0adce6e827fe8562fbc28bfd9c15571c66ca1f5f79"
+
+[[package]]
+name = "pkg-config"
+version = "0.3.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"
+
+[[package]]
+name = "zstd"
+version = "0.12.3+zstd.1.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76eea132fb024e0e13fd9c2f5d5d595d8a967aa72382ac2f9d39fcc95afd0806"
+dependencies = [
+ "zstd-safe",
+]
+
+[[package]]
+name = "zstd-demo"
+version = "0.1.0"
+dependencies = [
+ "zstd",
+]
+
+[[package]]
+name = "zstd-safe"
+version = "6.0.4+zstd.1.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7afb4b54b8910cf5447638cb54bf4e8a65cbedd783af98b98c62ffe91f185543"
+dependencies = [
+ "libc",
+ "zstd-sys",
+]
+
+[[package]]
+name = "zstd-sys"
+version = "2.0.7+zstd.1.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94509c3ba2fe55294d752b79842c530ccfab760192521df74a081a78d2b3c7f5"
+dependencies = [
+ "cc",
+ "libc",
+ "pkg-config",
+]
diff --git a/__compress/zstd-demo/Cargo.toml b/__compress/zstd-demo/Cargo.toml
new file mode 100644
index 0000000..ad19853
--- /dev/null
+++ b/__compress/zstd-demo/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "zstd-demo"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+zstd = "0.12.3"
diff --git a/__compress/zstd-demo/src/main.rs b/__compress/zstd-demo/src/main.rs
new file mode 100644
index 0000000..ab428b3
--- /dev/null
+++ b/__compress/zstd-demo/src/main.rs
@@ -0,0 +1,29 @@
+use std::collections::VecDeque;
+use std::io;
+use zstd::Encoder;
+
+fn main() {
+    let inputs = "hello world".repeat(100);
+    let outputs = compress_manually(1, inputs.as_bytes().to_vec().into());
+
+    println!("Inputs len: {}", inputs.len());
+    println!("Outputs len: {}", outputs.len());
+    println!("{:x?}", outputs);
+}
+
+// fn compress(level: i32) {
+//     zstd::stream::copy_encode(io::stdin(), io::stdout(), level).unwrap();
+// }
+// fn decompress() {
+//     zstd::stream::copy_decode(io::stdin(), io::stdout()).unwrap();
+// }
+
+// This function does the same thing, directly using an `Encoder`:
+fn compress_manually(level: i32, mut input: VecDeque<u8>) -> Vec<u8> {
+    let mut output: Vec<u8> = vec![];
+    let mut encoder = Encoder::new(&mut output, level).unwrap();
+    io::copy(&mut input, &mut encoder).unwrap();
+    encoder.finish().unwrap();
+    output
+}
+