diff --git a/Cargo.lock b/Cargo.lock
index e7db65e..824e64e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1373,7 +1373,7 @@ checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
  "libc",
  "rand_chacha",
- "rand_core",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -1383,7 +1383,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -1395,6 +1395,12 @@ dependencies = [
  "getrandom 0.2.16",
 ]
 
+[[package]]
+name = "rand_core"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "99d9a13982dcf210057a8a78572b2217b667c3beacbf3a0d8b454f6f82837d38"
+
 [[package]]
 name = "redox_syscall"
 version = "0.5.13"
@@ -1417,7 +1423,7 @@ dependencies = [
  "num-traits",
  "pkcs1",
  "pkcs8",
- "rand_core",
+ "rand_core 0.6.4",
  "signature",
  "spki",
  "subtle",
@@ -1548,7 +1554,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77549399552de45a898a580c1b41d445bf730df867cc44e6c0233bbc4b8329de"
 dependencies = [
  "digest",
- "rand_core",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -2071,6 +2077,20 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "varo"
+version = "0.1.0"
+dependencies = [
+ "blake3",
+ "digest",
+ "rand_core 0.9.3",
+ "serde",
+ "serde_json",
+ "tempfile",
+ "vanth",
+ "vanth_derive",
+]
+
 [[package]]
 name = "vcpkg"
 version = "0.2.15"
diff --git a/Cargo.toml b/Cargo.toml
index 6606edd..1219416 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ edition = "2024"
 clap = { version = "4.5.42", features = ["derive"] }
 bevy_app = "0.16.1"
 bevy_ecs = "0.16.1"
-bitcode = "0.6.6"
+bincode = "2.0.1"
 serde = { version = "1.0.219", features = ["derive"] }
 serde_json = "1.0.140"
 digest = "0.10.7"
@@ -21,3 +21,4 @@ proc-macro2 = "1.0"
 sqlx = "0.8.6"
 rusqlite = { version = "0.32.1", features = ["bundled"] }
 tempfile = "3.12.0"
+rand_core = "0.9.3"
diff --git a/crates/vanth/src/lib.rs b/crates/vanth/src/lib.rs
index 8796aa6..120c1ec 100644
--- a/crates/vanth/src/lib.rs
+++ b/crates/vanth/src/lib.rs
@@ -180,3 +180,8 @@ impl Plugin for VanthPlugin {
 // fn run_reference_tasks(tasks: Query<(&ReferenceGetTask<>)>) {
 
 // }
+
+/// A world which Vanth entities live in. Lifetimes `'v` of [`Vanth<'v>`] types are tied to the lifetime of the `Root`.
+pub struct Root {
+    
+}
diff --git a/crates/vanth/tests/integration/main.rs b/crates/vanth/tests/integration/main.rs
index 3c9841a..3044c26 100644
--- a/crates/vanth/tests/integration/main.rs
+++ b/crates/vanth/tests/integration/main.rs
@@ -4,3 +4,4 @@ use vanth::{Component, Node, Reference};
 mod derive;
 mod fs;
 mod store;
+mod reference;
diff --git a/crates/vanth/tests/integration/reference.rs b/crates/vanth/tests/integration/reference.rs
new file mode 100644
index 0000000..a926e3b
--- /dev/null
+++ b/crates/vanth/tests/integration/reference.rs
@@ -0,0 +1,20 @@
+use bevy_ecs::{component::Component, entity::Entity, event::{Event, EventWriter}, system::Query};
+
+#[derive(Event)]
+struct LevelUpEvent<T> {
+    inner: T,
+}
+
+#[derive(Component)]
+struct FooTask {
+    field: i32,
+}
+
+fn player_level_up(
+    mut ev_levelup: EventWriter<LevelUpEvent<i32>>,
+    query: Query<(Entity, &FooTask)>,
+) {
+    for (entity, xp) in query.iter() {
+        ev_levelup.write(LevelUpEvent::<i32> { inner: 5 });
+    }
+}
diff --git a/crates/varo/Cargo.toml b/crates/varo/Cargo.toml
new file mode 100644
index 0000000..4436fc2
--- /dev/null
+++ b/crates/varo/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "varo"
+version.workspace = true
+edition.workspace = true
+
+[lib]
+path = "src/lib.rs"
+
+[dependencies]
+digest.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+blake3.workspace = true
+vanth = { path = "../vanth" }
+vanth_derive = { path = "../vanth_derive" }
+rand_core.workspace = true
+
+[dev-dependencies]
+tempfile = { workspace = true }
diff --git a/crates/varo/src/lib.rs b/crates/varo/src/lib.rs
new file mode 100644
index 0000000..409af7c
--- /dev/null
+++ b/crates/varo/src/lib.rs
@@ -0,0 +1,49 @@
+use rand_core::SeedableRng;
+use serde::{Deserialize, Serialize};
+use vanth_derive::Vanth;
+
+#[derive(Clone, Debug, Deserialize, Serialize, Vanth)]
+pub struct Rng {
+    // TODO: RNG
+}
+
+impl Rng {
+    // TODO
+}
+
+pub trait Varo {
+    /// Produce a random 
+    fn next(digest: &mut Rng) -> Self;
+}
+
+#[derive(Clone, Debug, Deserialize, Serialize, Vanth)]
+pub struct Distribution {
+    /// 0th element is the mean, 1st is the variance etc.
+    pub moments: Vec<f32>,
+}
+
+impl Distribution {
+    pub fn sample(digest: &mut Rng) -> f32 {
+        todo!()
+    }
+}
+
+#[derive(Clone, Debug, Deserialize, Serialize, Vanth)]
+pub struct Score {
+    value: f32,
+}
+
+#[derive(Clone, Debug, Deserialize, Serialize, Vanth)]
+pub struct OptimizationResult {
+    /// List of pairs of evaluation score and Rng used to generate the value.
+    values: Vec<(Rng, f32)>
+}
+
+pub fn optimize<T: Varo>(evaluator: impl Fn(T) -> Score, rng: &mut Rng, rounds: u32) -> OptimizationResult {
+    // TODO:
+    // `for i in 0..rounds`: create a clone of `rng` and feed it `i`.
+    // Call T::next() and pass it to the evaluator.
+    // Return a sorted list, highest scores first.
+    
+    todo!()
+}