diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..766dd08
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,95 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "c2-chacha"
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diff --git a/Cargo.toml b/Cargo.toml
index 77a04db..4e8d54e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,4 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+rand = "0.7"
diff --git a/src/main.rs b/src/main.rs
index e7a11a9..ba5f5ca 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,19 @@
-fn main() {
-    println!("Hello, world!");
+mod random;
+
+#[derive(Debug, Copy, Clone)]
+pub enum Tetrino {
+    I,
+    O,
+    T,
+    S,
+    Z,
+    J,
+    L,
+}
+
+fn main() {
+    let mut rs = random::RandomSystem::new();
+    for _ in 0..1000000 {
+        rs.get_tetrino();
+    }
 }
diff --git a/src/random.rs b/src/random.rs
new file mode 100644
index 0000000..5f09e6e
--- /dev/null
+++ b/src/random.rs
@@ -0,0 +1,42 @@
+use crate::Tetrino;
+use rand::{rngs::ThreadRng, seq::SliceRandom, thread_rng};
+
+pub struct RandomSystem {
+    rng: ThreadRng,
+    bag: [Tetrino; 7],
+    cur_pos: usize,
+}
+
+impl RandomSystem {
+    pub fn new() -> Self {
+        let rng = thread_rng();
+        RandomSystem {
+            rng: rng,
+            bag: [Tetrino::I; 7],
+            cur_pos: 0,
+        }
+    }
+
+    pub fn get_tetrino(&mut self) -> Tetrino {
+        if self.cur_pos == 0 {
+            self.refresh_bag();
+        }
+        let to_return = self.bag[self.cur_pos];
+        self.cur_pos = (self.cur_pos + 1) % 7;
+        to_return
+    }
+
+    fn refresh_bag(&mut self) {
+        self.bag = [
+            Tetrino::I,
+            Tetrino::O,
+            Tetrino::T,
+            Tetrino::S,
+            Tetrino::Z,
+            Tetrino::J,
+            Tetrino::L,
+        ];
+        self.bag.shuffle(&mut self.rng);
+        self.cur_pos = 0;
+    }
+}