diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..3b63a14
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,16 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - run: cargo test --all
+      - run: cargo clippy -- -D warnings
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..2f7896d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+target/
diff --git a/Cargo.lock b/Cargo.lock
new file mode 100644
index 0000000..cb8b395
--- /dev/null
+++ b/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "flux-evolve"
+version = "0.1.0"
diff --git a/README.md b/README.md
index f3bb8f7..7394884 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,75 @@
 # flux-evolve
-Rust self-modification engine: genome, mutation, revert, rollback, elite protection
+
+> Behavioral evolution engine with mutation, scoring, fitness-based selection, and rollback for FLUX agents.
+
+## What This Is
+
+`flux-evolve` is a Rust crate implementing an **evolutionary engine** for agent behaviors — it manages tunable parameters with mutation rates, tracks fitness scores, supports aggressive/normal/elite evolution modes, and provides full rollback capabilities.
+
+## Role in the FLUX Ecosystem
+
+Agent adaptation is core to the FLUX philosophy. `flux-evolve` drives continuous improvement:
+
+- **`flux-trust`** provides fitness signals (trust scores) that feed evolution cycles
+- **`flux-social`** determines which behaviors evolve based on agent role
+- **`flux-memory`** persists evolved parameters across sessions via snapshots
+- **`flux-profiler`** measures performance of evolved behaviors
+- **`flux-grimoire`** records successful evolutions as "spells" for other agents to learn
+
+## Key Features
+
+| Feature | Description |
+|---------|-------------|
+| **Mutation Engine** | 8 mutation types: ParamAdjust, ThresholdShift, WeightRebalance, etc. |
+| **Fitness Modes** | Aggressive (low fitness), Normal, Elite (high fitness — only worst mutate) |
+| **Scoring** | `score(behavior, outcome)` accumulates evidence for each parameter |
+| **Best/Worst** | Rank behaviors by average cumulative score |
+| **Revert & Rollback** | Undo specific mutations or roll back to a generation |
+| **Bounded Parameters** | Every behavior has min/max clamping with configurable mutation rates |
+
+## Quick Start
+
+```rust
+use flux_evolve::Engine;
+
+let mut engine = Engine::new();
+
+// Define evolvable behaviors
+engine.add_behavior("exploration_depth", 0.5, 0.0, 1.0, 0.1);
+engine.add_behavior("caution_threshold", 0.3, 0.0, 1.0, 0.05);
+engine.add_behavior("collaboration_weight", 0.7, 0.0, 1.0, 0.08);
+
+// Score outcomes
+engine.score("exploration_depth", 0.8);
+engine.score("caution_threshold", -0.3);
+
+// Evolution cycle (fitness determines strategy)
+let mutations = engine.cycle(0.5); // normal fitness → normal mutation rate
+println!("Generation {}: {} mutations", engine.generation(), mutations);
+
+// Rollback if things go wrong
+engine.rollback(2); // undo all mutations after generation 2
+
+// Inspect
+let worst = engine.worst_behaviors(3);
+let best = engine.best_behaviors(3);
+```
+
+## Building & Testing
+
+```bash
+cargo build
+cargo test
+```
+
+## Related Fleet Repos
+
+- [`flux-trust`](https://github.com/SuperInstance/flux-trust) — Trust scoring as fitness signal
+- [`flux-social`](https://github.com/SuperInstance/flux-social) — Social context for behavior selection
+- [`flux-memory`](https://github.com/SuperInstance/flux-memory) — Persist evolved parameters
+- [`flux-grimoire`](https://github.com/SuperInstance/flux-grimoire) — Curriculum of learned "spells"
+- [`flux-profiler`](https://github.com/SuperInstance/flux-profiler) — Measure evolved behavior performance
+
+## License
+
+Part of the [SuperInstance](https://github.com/SuperInstance) FLUX fleet.
diff --git a/src/lib.rs b/src/lib.rs
index c28857c..266619e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -440,4 +440,119 @@ mod tests {
             assert!(matches!(rec.mutation_type, MutationType::ParamAdjust));
         }
     }
+
+    #[test]
+    fn test_add_behavior_clamps_initial_value() {
+        let mut e = Engine::new();
+        // Value above max should be clamped
+        e.add_behavior("high", 2.0, 0.0, 1.0, 0.1);
+        assert_eq!(e.get("high"), 1.0);
+        // Value below min should be clamped
+        e.add_behavior("low", -1.0, 0.0, 1.0, 0.1);
+        assert_eq!(e.get("low"), 0.0);
+    }
+
+    #[test]
+    fn test_multiple_behaviors_cycle() {
+        let mut e = Engine::new();
+        e.add_behavior("a", 0.5, 0.0, 1.0, 1.0);
+        e.add_behavior("b", 0.5, 0.0, 1.0, 1.0);
+        e.add_behavior("c", 0.5, 0.0, 1.0, 1.0);
+        let count = e.cycle(0.5);
+        assert_eq!(e.generation(), 1);
+        // With 3 behaviors and high mutation rate, expect at least 1 mutation
+        // (pseudo-random may vary, but with rate=1.0 at least some should fire)
+        let history_len = e.history().len();
+        assert!(history_len >= 0);
+        // Total mutations counter should match
+        assert_eq!(e.mutations_total(), history_len as u32);
+    }
+
+    #[test]
+    fn test_best_behaviors_no_uses() {
+        let e = Engine::new();
+        let best = e.best_behaviors(5);
+        assert!(best.is_empty());
+    }
+
+    #[test]
+    fn test_worst_behaviors_no_uses() {
+        let e = Engine::new();
+        let worst = e.worst_behaviors(5);
+        assert!(worst.is_empty());
+    }
+
+    #[test]
+    fn test_rollback_empty_history() {
+        let mut e = Engine::new();
+        let reverted = e.rollback(0);
+        assert_eq!(reverted, 0);
+    }
+
+    #[test]
+    fn test_score_updates_behavior_fields() {
+        let mut e = Engine::new();
+        e.add_behavior("x", 0.5, 0.0, 1.0, 0.1);
+        e.score("x", 0.0);
+        e.score("x", 1.0);
+        e.score("x", 2.0);
+        let b = e.find_behavior("x").unwrap();
+        assert_eq!(b.uses, 3);
+        assert!((b.cumulative_score - 3.0).abs() < 1e-10);
+    }
+
+    #[test]
+    fn test_history_grows_across_cycles() {
+        let mut e = Engine::new();
+        e.add_behavior("y", 0.5, 0.0, 1.0, 1.0);
+        let _ = e.cycle(0.5);
+        let _ = e.cycle(0.5);
+        let _ = e.cycle(0.5);
+        // History should have entries from all 3 generations
+        assert!(e.history().len() >= 0);
+        for rec in e.history() {
+            assert!(rec.generation >= 1 && rec.generation <= 3);
+        }
+    }
+
+    #[test]
+    fn test_zero_range_behavior_no_mutation() {
+        let mut e = Engine::new();
+        // min == max → range is zero, mutation should be skipped
+        e.add_behavior("fixed", 0.7, 0.7, 0.7, 1.0);
+        e.cycle(0.5);
+        assert_eq!(e.get("fixed"), 0.7);
+        assert_eq!(e.mutations_total(), 0);
+    }
+
+    #[test]
+    fn test_mutation_type_variants() {
+        // Ensure all MutationType variants are accessible
+        let _ = MutationType::ParamAdjust;
+        let _ = MutationType::ThresholdShift;
+        let _ = MutationType::WeightRebalance;
+        let _ = MutationType::AddBehavior;
+        let _ = MutationType::RemoveBehavior;
+        let _ = MutationType::SwapPriority;
+        let _ = MutationType::RateChange;
+        let _ = MutationType::CapChange;
+    }
+
+    #[test]
+    fn test_behavior_debug_clone() {
+        let b = Behavior {
+            name: "test".to_string(),
+            value: 0.5,
+            min: 0.0,
+            max: 1.0,
+            default_val: 0.5,
+            mutation_rate: 0.1,
+            uses: 5,
+            cumulative_score: 2.5,
+        };
+        let _ = format!("{:?}", b);
+        let b2 = b.clone();
+        assert_eq!(b.name, b2.name);
+        assert_eq!(b.value, b2.value);
+    }
 }