diff --git a/Cargo.lock b/Cargo.lock
index 1b9b7d25..21a07046 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -453,6 +453,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "dissimilar"
+version = "1.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8975ffdaa0ef3661bfe02dbdcc06c9f829dfafe6a3c474de366a8d5e44276921"
+
 [[package]]
 name = "either"
 version = "1.15.0"
@@ -496,6 +502,16 @@ dependencies = [
  "windows-sys 0.61.1",
 ]
 
+[[package]]
+name = "expect-test"
+version = "1.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63af43ff4431e848fb47472a920f14fa71c24de13255a5692e93d4e90302acb0"
+dependencies = [
+ "dissimilar",
+ "once_cell",
+]
+
 [[package]]
 name = "fallible-iterator"
 version = "0.3.0"
@@ -1137,6 +1153,7 @@ dependencies = [
 name = "mchprs"
 version = "0.4.1"
 dependencies = [
+ "expect-test",
  "mchprs_blocks",
  "mchprs_core",
  "mchprs_redpiler",
diff --git a/Cargo.toml b/Cargo.toml
index 01649bf9..25a46951 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -46,6 +46,7 @@ mchprs_blocks = { path = "./crates/blocks" }
 mchprs_redpiler = { path = "./crates/redpiler" }
 mchprs_redstone = { path = "./crates/redstone" }
 paste = { workspace = true }
+expect-test = { workspace = true }
 
 [workspace.dependencies]
 toml = "0.8"
@@ -86,3 +87,4 @@ tracing-appender = "0.2"
 paste = "1.0"
 chrono = "0.4"
 clap = { version = "4.5", features = ["derive"] }
+expect-test = "1.5"
diff --git a/crates/redpiler/src/lib.rs b/crates/redpiler/src/lib.rs
index 36d3c162..0f5162db 100644
--- a/crates/redpiler/src/lib.rs
+++ b/crates/redpiler/src/lib.rs
@@ -5,16 +5,21 @@ mod ril;
 mod task_monitor;
 
 use backend::{BackendDispatcher, JITBackend};
+
 use mchprs_blocks::blocks::Block;
 use mchprs_blocks::BlockPos;
 use mchprs_world::{for_each_block_mut_optimized, TickEntry, World};
-use passes::make_default_pass_manager;
+
 use std::sync::Arc;
 use std::time::Instant;
 use tracing::{debug, error, trace, warn};
 
 pub use task_monitor::TaskMonitor;
 
+pub use compile_graph::*;
+pub use passes::PassManager;
+pub use ril::DumpGraph;
+
 fn block_powered_mut(block: &mut Block) -> Option<&mut bool> {
     Some(match block {
         Block::RedstoneComparator { comparator } => &mut comparator.powered,
@@ -136,7 +141,7 @@ impl Compiler {
         let start = Instant::now();
 
         let input = CompilerInput { world, bounds };
-        let pass_manager = make_default_pass_manager::<W>();
+        let pass_manager = PassManager::default();
         let graph = pass_manager.run_passes(&options, &input, monitor.clone());
 
         if monitor.cancelled() {
diff --git a/crates/redpiler/src/passes/mod.rs b/crates/redpiler/src/passes/mod.rs
index 07dbb4d1..922780df 100644
--- a/crates/redpiler/src/passes/mod.rs
+++ b/crates/redpiler/src/passes/mod.rs
@@ -23,22 +23,6 @@ use std::sync::Arc;
 use std::time::Instant;
 use tracing::{debug, trace};
 
-pub const fn make_default_pass_manager<'w, W: World>() -> PassManager<'w, W> {
-    PassManager::new(&[
-        &identify_nodes::IdentifyNodes,
-        &input_search::InputSearch,
-        &clamp_weights::ClampWeights,
-        &dedup_links::DedupLinks,
-        &constant_fold::ConstantFold,
-        &analysis::ss_range_analysis::SSRangeAnalysis,
-        &unreachable_output::UnreachableOutput,
-        &constant_coalesce::ConstantCoalesce,
-        &coalesce::Coalesce,
-        &prune_orphans::PruneOrphans,
-        &export_graph::ExportGraph,
-    ])
-}
-
 pub trait AnalysisInfo: Any {}
 
 #[derive(Default)]
@@ -64,6 +48,24 @@ pub struct PassManager<'p, W: World> {
     passes: &'p [&'p dyn Pass<W>],
 }
 
+impl<'p, W: World> Default for PassManager<'p, W> {
+    fn default() -> Self {
+        Self::new(&[
+            &identify_nodes::IdentifyNodes,
+            &input_search::InputSearch,
+            &clamp_weights::ClampWeights,
+            &dedup_links::DedupLinks,
+            &constant_fold::ConstantFold,
+            &analysis::ss_range_analysis::SSRangeAnalysis,
+            &unreachable_output::UnreachableOutput,
+            &constant_coalesce::ConstantCoalesce,
+            &coalesce::Coalesce,
+            &prune_orphans::PruneOrphans,
+            &export_graph::ExportGraph,
+        ])
+    }
+}
+
 impl<'p, W: World> PassManager<'p, W> {
     pub const fn new(passes: &'p [&dyn Pass<W>]) -> Self {
         Self { passes }
@@ -106,13 +108,13 @@ impl<'p, W: World> PassManager<'p, W> {
 
             if options.print_after_all {
                 debug!("Printing circuit after pass: {}", pass.name());
-                graph.dump();
+                graph.dump_to_stderr();
             }
         }
 
         if options.print_before_backend {
             debug!("Printing circuit before backend compile:");
-            graph.dump();
+            graph.dump_to_stderr();
         }
 
         graph
diff --git a/crates/redpiler/src/ril.rs b/crates/redpiler/src/ril.rs
index f989326f..ae1b35aa 100644
--- a/crates/redpiler/src/ril.rs
+++ b/crates/redpiler/src/ril.rs
@@ -227,13 +227,18 @@ impl<'a> fmt::Display for GraphDumper<'a> {
 }
 
 pub trait DumpGraph {
-    fn dump(&self);
+    fn dump_to_stderr(&self);
+    fn dump_to_string(&self) -> String;
 }
 
 impl DumpGraph for CompileGraph {
-    fn dump(&self) {
+    fn dump_to_stderr(&self) {
         eprintln!("{}", GraphDumper { graph: self });
     }
+
+    fn dump_to_string(&self) -> String {
+        format!("{}", GraphDumper { graph: self })
+    }
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 3e711fe1..5064cd65 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -31,6 +31,11 @@ impl TestWorld {
         }
     }
 
+    pub fn bounds(&self) -> (BlockPos, BlockPos) {
+        let max_coord = self.size * 16 - 1;
+        (pos(0, 0, 0), pos(max_coord, max_coord, max_coord))
+    }
+
     fn get_chunk_index_for_chunk(&self, chunk_x: i32, chunk_z: i32) -> usize {
         (chunk_x * self.size + chunk_z).unsigned_abs() as usize
     }
diff --git a/tests/frontend.rs b/tests/frontend.rs
new file mode 100644
index 00000000..60ec245b
--- /dev/null
+++ b/tests/frontend.rs
@@ -0,0 +1,296 @@
+mod common;
+use common::*;
+
+use expect_test::expect_file;
+
+use mchprs_blocks::{
+    blocks::{Block, ComparatorMode, Lever, LeverFace},
+    BlockDirection,
+};
+use mchprs_redpiler::{CompilerInput, CompilerOptions, DumpGraph, PassManager};
+use mchprs_world::{TickPriority, World};
+
+enum OptLevel {
+    Unoptimized,
+    Optimized,
+}
+
+fn test_frontend(world: &TestWorld, expected_ril: expect_test::ExpectFile, opt_level: OptLevel) {
+    let compile_options = match opt_level {
+        OptLevel::Unoptimized => CompilerOptions {
+            optimize: false,
+            ..Default::default()
+        },
+        OptLevel::Optimized => CompilerOptions {
+            optimize: true,
+            io_only: true,
+            ..Default::default()
+        },
+    };
+    let pass_manager = PassManager::default();
+    let graph = pass_manager.run_passes(
+        &compile_options,
+        &CompilerInput {
+            world,
+            bounds: world.bounds(),
+        },
+        Default::default(),
+    );
+    let ril = graph.dump_to_string();
+    expected_ril.assert_eq(&ril);
+}
+
+const SANDSTONE: Block = Block::Sandstone {};
+const REDSTONE_BLOCK: Block = Block::RedstoneBlock {};
+
+const REDSTONE_LAMP_UNLIT: Block = Block::RedstoneLamp { lit: false };
+const REDSTONE_LAMP_LIT: Block = Block::RedstoneLamp { lit: true };
+
+const LEVER_GROUND_DEACTIVATED: Block = Block::Lever {
+    lever: Lever {
+        face: LeverFace::Floor,
+        facing: BlockDirection::North,
+        powered: false,
+    },
+};
+
+const TORCH_GROUND_UNLIT: Block = Block::RedstoneTorch { lit: false };
+const TORCH_GROUND_LIT: Block = Block::RedstoneTorch { lit: true };
+
+#[test]
+fn lever_on_constantly_powered_lamp() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(0, 0, 0), REDSTONE_BLOCK);
+    world.set_block(pos(0, 1, 0), REDSTONE_LAMP_LIT);
+    world.set_block(pos(0, 2, 0), LEVER_GROUND_DEACTIVATED);
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/lever_on_constantly_powered_lamp_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    // TODO: Missed optimization:
+    // The lever has no effect on the lamp.
+    let expected = expect_file!["test_expects/lever_on_constantly_powered_lamp_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn lit_torch_with_no_inputs() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(0, 0, 0), SANDSTONE);
+    world.set_block(pos(0, 1, 0), TORCH_GROUND_LIT);
+    world.set_block(pos(0, 2, 0), REDSTONE_LAMP_LIT);
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/lit_torch_with_no_inputs_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/lit_torch_with_no_inputs_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn unlit_torch_on_redstone_block() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(0, 0, 0), REDSTONE_BLOCK);
+    world.set_block(pos(0, 1, 0), TORCH_GROUND_UNLIT);
+    world.set_block(pos(0, 2, 0), REDSTONE_LAMP_UNLIT);
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/unlit_torch_on_redstone_block_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/unlit_torch_on_redstone_block_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn lever_with_many_edges_to_same_lamp() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(1, 1, 1), REDSTONE_LAMP_UNLIT);
+    world.set_block(pos(1, 2, 1), LEVER_GROUND_DEACTIVATED);
+    make_wire(&mut world, pos(0, 1, 1));
+    make_wire(&mut world, pos(1, 1, 0));
+    make_wire(&mut world, pos(2, 1, 1));
+    make_wire(&mut world, pos(1, 1, 2));
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/lever_with_many_edges_to_same_lamp_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/lever_with_many_edges_to_same_lamp_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn long_redstone_wire() {
+    let mut world = TestWorld::new(2);
+    make_lever(&mut world, pos(0, 1, 0));
+    world.set_block(pos(0, 1, 20), REDSTONE_LAMP_UNLIT);
+    for z in 1..20 {
+        make_wire(&mut world, pos(0, 1, z));
+    }
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/long_redstone_wire_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/long_redstone_wire_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn long_redstone_wire_with_comparator() {
+    let mut world = TestWorld::new(1);
+    make_lever(&mut world, pos(0, 1, 0));
+    for z in 1..10 {
+        make_wire(&mut world, pos(0, 1, z));
+    }
+    make_comparator(
+        &mut world,
+        pos(0, 1, 10),
+        ComparatorMode::Compare,
+        BlockDirection::North,
+    );
+    for z in 11..20 {
+        make_wire(&mut world, pos(0, 1, z));
+    }
+    world.set_block(pos(0, 1, 20), REDSTONE_LAMP_UNLIT);
+
+    // Unoptimized
+    // FIXME: Unoptimized mode should not be removing edges.
+    let expected = expect_file!["test_expects/long_redstone_wire_with_comparator_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/long_redstone_wire_with_comparator_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn unpowered_repeater_clock() {
+    let mut world = TestWorld::new(1);
+    make_wire(&mut world, pos(0, 1, 0));
+    make_repeater(&mut world, pos(0, 1, 1), 1, BlockDirection::East);
+    world.set_block(pos(0, 1, 2), REDSTONE_LAMP_UNLIT);
+    make_wire(&mut world, pos(1, 1, 2));
+    make_repeater(&mut world, pos(1, 1, 1), 1, BlockDirection::West);
+    world.set_block(pos(1, 1, 0), REDSTONE_LAMP_UNLIT);
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/unpowered_repeater_clock_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    let expected = expect_file!["test_expects/unpowered_repeater_clock_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn repeater_clock_duplicated_repeaters() {
+    //  L  W  W  W  W  W  W
+    //    RN RN RN RS RS RS
+    //  L  W  W  W  W  W  W
+    let mut world = TestWorld::new(1);
+    make_lever(&mut world, pos(0, 1, 0));
+    world.set_block(pos(0, 0, 2), REDSTONE_LAMP_UNLIT);
+    for x in 1..7 {
+        let repeater_direction = match x {
+            ..4 => BlockDirection::North,
+            _ => BlockDirection::South,
+        };
+        make_wire(&mut world, pos(x, 1, 0));
+        make_repeater(&mut world, pos(x, 1, 1), 1, repeater_direction);
+        make_wire(&mut world, pos(x, 1, 2));
+    }
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/repeater_clock_duplicated_repeaters_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    // TODO: Missed optimization:
+    // A lot of redundant edges.
+    let expected = expect_file!["test_expects/repeater_clock_duplicated_repeaters_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn compare_mode_full_ss_rear_input() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(0, 1, 0), REDSTONE_LAMP_UNLIT);
+    make_comparator(
+        &mut world,
+        pos(0, 1, 1),
+        ComparatorMode::Compare,
+        BlockDirection::South,
+    );
+    make_wire(&mut world, pos(0, 1, 2));
+    make_lever(&mut world, pos(0, 1, 3)); // rear input
+    make_repeater(&mut world, pos(1, 1, 1), 1, BlockDirection::East);
+    make_lever(&mut world, pos(2, 1, 1)); // side input
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/compare_mode_full_ss_rear_input_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    // TODO: Missed optimization:
+    // The side input of the comparator has no effect on the comparator.
+    let expected = expect_file!["test_expects/compare_mode_full_ss_rear_input_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn repeater_chain_with_pending_update() {
+    let mut world = TestWorld::new(1);
+    world.set_block(pos(0, 1, 0), REDSTONE_BLOCK);
+    make_repeater(&mut world, pos(1, 1, 0), 1, BlockDirection::West);
+    make_repeater(&mut world, pos(2, 1, 0), 1, BlockDirection::West);
+    world.set_block(pos(3, 1, 0), REDSTONE_LAMP_UNLIT);
+    // schedule an update for the first repeater
+    world.schedule_tick(pos(1, 1, 0), 1, TickPriority::Normal);
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/repeater_chain_with_pending_update_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    // FIXME: Illegal optimization:
+    // The repeaters must not be optimized away because they become powered in the next ticks.
+    let expected = expect_file!["test_expects/repeater_chain_with_pending_update_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
+
+#[test]
+fn multiple_different_constants() {
+    let mut world = TestWorld::new(1);
+    for x in 0..4 {
+        make_wire(&mut world, pos(x, 1, 1));
+    }
+    world.set_block(pos(0, 1, 0), REDSTONE_BLOCK);
+    world.set_block(pos(2, 1, 0), REDSTONE_BLOCK);
+    world.set_block(pos(4, 1, 0), REDSTONE_LAMP_UNLIT);
+    make_comparator(
+        &mut world,
+        pos(4, 1, 1),
+        ComparatorMode::Subtract,
+        BlockDirection::South,
+    );
+    make_lever(&mut world, pos(4, 1, 2));
+
+    // Unoptimized
+    let expected = expect_file!["test_expects/multiple_different_constants_UNOPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Unoptimized);
+
+    // Optimized
+    // TODO: Missed optimization:
+    // Redundant edge from constant to comparator.
+    let expected = expect_file!["test_expects/multiple_different_constants_OPTIMIZED"];
+    test_frontend(&world, expected, OptLevel::Optimized);
+}
diff --git a/tests/test_expects/compare_mode_full_ss_rear_input_OPTIMIZED b/tests/test_expects/compare_mode_full_ss_rear_input_OPTIMIZED
new file mode 100644
index 00000000..6d7b4e5e
--- /dev/null
+++ b/tests/test_expects/compare_mode_full_ss_rear_input_OPTIMIZED
@@ -0,0 +1,7 @@
+circuit {
+  %0 = lamp false, [%1:0]  # Loc: (0, 1, 0)
+  %1 = comparator compare, none, false, 0, [%2:0], [%3:0]  # Loc: (0, 1, 1)
+  %2 = lever false  # Loc: (0, 1, 3)
+  %3 = repeater 1, true, false, false, [%4:0], []  # Loc: (1, 1, 1)
+  %4 = lever false  # Loc: (2, 1, 1)
+}
\ No newline at end of file
diff --git a/tests/test_expects/compare_mode_full_ss_rear_input_UNOPTIMIZED b/tests/test_expects/compare_mode_full_ss_rear_input_UNOPTIMIZED
new file mode 100644
index 00000000..a7dc6202
--- /dev/null
+++ b/tests/test_expects/compare_mode_full_ss_rear_input_UNOPTIMIZED
@@ -0,0 +1,8 @@
+circuit {
+  %0 = lamp false, [%1:0]  # Loc: (0, 1, 0)
+  %1 = comparator compare, none, false, 0, [%3:0], [%4:0]  # Loc: (0, 1, 1)
+  %2 = wire 0, [%3:0]  # Loc: (0, 1, 2)
+  %3 = lever false  # Loc: (0, 1, 3)
+  %4 = repeater 1, true, false, false, [%5:0], []  # Loc: (1, 1, 1)
+  %5 = lever false  # Loc: (2, 1, 1)
+}
\ No newline at end of file
diff --git a/tests/test_expects/lever_on_constantly_powered_lamp_OPTIMIZED b/tests/test_expects/lever_on_constantly_powered_lamp_OPTIMIZED
new file mode 100644
index 00000000..1ca7a29d
--- /dev/null
+++ b/tests/test_expects/lever_on_constantly_powered_lamp_OPTIMIZED
@@ -0,0 +1,5 @@
+circuit {
+  %1 = lamp true, [%3:0, %2:0]  # Loc: (0, 1, 0)
+  %2 = lever false  # Loc: (0, 2, 0)
+  %3 = constant 15
+}
\ No newline at end of file
diff --git a/tests/test_expects/lever_on_constantly_powered_lamp_UNOPTIMIZED b/tests/test_expects/lever_on_constantly_powered_lamp_UNOPTIMIZED
new file mode 100644
index 00000000..aa4f2fd7
--- /dev/null
+++ b/tests/test_expects/lever_on_constantly_powered_lamp_UNOPTIMIZED
@@ -0,0 +1,5 @@
+circuit {
+  %0 = constant 15  # Loc: (0, 0, 0)
+  %1 = lamp true, [%0:0, %2:0]  # Loc: (0, 1, 0)
+  %2 = lever false  # Loc: (0, 2, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/lever_with_many_edges_to_same_lamp_OPTIMIZED b/tests/test_expects/lever_with_many_edges_to_same_lamp_OPTIMIZED
new file mode 100644
index 00000000..a0601fd3
--- /dev/null
+++ b/tests/test_expects/lever_with_many_edges_to_same_lamp_OPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %0 = lamp false, [%1:0]  # Loc: (1, 1, 1)
+  %1 = lever false  # Loc: (1, 2, 1)
+}
\ No newline at end of file
diff --git a/tests/test_expects/lever_with_many_edges_to_same_lamp_UNOPTIMIZED b/tests/test_expects/lever_with_many_edges_to_same_lamp_UNOPTIMIZED
new file mode 100644
index 00000000..66e6a0c3
--- /dev/null
+++ b/tests/test_expects/lever_with_many_edges_to_same_lamp_UNOPTIMIZED
@@ -0,0 +1,8 @@
+circuit {
+  %0 = wire 0, [%4:0]  # Loc: (0, 1, 1)
+  %1 = wire 0, [%4:0]  # Loc: (1, 1, 0)
+  %2 = lamp false, [%4:0, %4:0, %4:0, %4:0, %4:0]  # Loc: (1, 1, 1)
+  %3 = wire 0, [%4:0]  # Loc: (1, 1, 2)
+  %4 = lever false  # Loc: (1, 2, 1)
+  %5 = wire 0, [%4:0]  # Loc: (2, 1, 1)
+}
\ No newline at end of file
diff --git a/tests/test_expects/lit_torch_with_no_inputs_OPTIMIZED b/tests/test_expects/lit_torch_with_no_inputs_OPTIMIZED
new file mode 100644
index 00000000..c725ccf4
--- /dev/null
+++ b/tests/test_expects/lit_torch_with_no_inputs_OPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %1 = lamp true, [%2:0]  # Loc: (0, 2, 0)
+  %2 = constant 15
+}
\ No newline at end of file
diff --git a/tests/test_expects/lit_torch_with_no_inputs_UNOPTIMIZED b/tests/test_expects/lit_torch_with_no_inputs_UNOPTIMIZED
new file mode 100644
index 00000000..0c563faa
--- /dev/null
+++ b/tests/test_expects/lit_torch_with_no_inputs_UNOPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %0 = torch true, []  # Loc: (0, 1, 0)
+  %1 = lamp true, [%0:0]  # Loc: (0, 2, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/long_redstone_wire_OPTIMIZED b/tests/test_expects/long_redstone_wire_OPTIMIZED
new file mode 100644
index 00000000..c9cf3ece
--- /dev/null
+++ b/tests/test_expects/long_redstone_wire_OPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %0 = lever false  # Loc: (0, 1, 0)
+  %1 = lamp false, []  # Loc: (0, 1, 20)
+}
\ No newline at end of file
diff --git a/tests/test_expects/long_redstone_wire_UNOPTIMIZED b/tests/test_expects/long_redstone_wire_UNOPTIMIZED
new file mode 100644
index 00000000..0acf3f77
--- /dev/null
+++ b/tests/test_expects/long_redstone_wire_UNOPTIMIZED
@@ -0,0 +1,23 @@
+circuit {
+  %0 = lever false  # Loc: (0, 1, 0)
+  %1 = wire 0, [%0:0]  # Loc: (0, 1, 1)
+  %2 = wire 0, [%0:1]  # Loc: (0, 1, 2)
+  %3 = wire 0, [%0:2]  # Loc: (0, 1, 3)
+  %4 = wire 0, [%0:3]  # Loc: (0, 1, 4)
+  %5 = wire 0, [%0:4]  # Loc: (0, 1, 5)
+  %6 = wire 0, [%0:5]  # Loc: (0, 1, 6)
+  %7 = wire 0, [%0:6]  # Loc: (0, 1, 7)
+  %8 = wire 0, [%0:7]  # Loc: (0, 1, 8)
+  %9 = wire 0, [%0:8]  # Loc: (0, 1, 9)
+  %10 = wire 0, [%0:9]  # Loc: (0, 1, 10)
+  %11 = wire 0, [%0:10]  # Loc: (0, 1, 11)
+  %12 = wire 0, [%0:11]  # Loc: (0, 1, 12)
+  %13 = wire 0, [%0:12]  # Loc: (0, 1, 13)
+  %14 = wire 0, [%0:13]  # Loc: (0, 1, 14)
+  %15 = wire 0, [%0:14]  # Loc: (0, 1, 15)
+  %16 = wire 0, []  # Loc: (0, 1, 16)
+  %17 = wire 0, []  # Loc: (0, 1, 17)
+  %18 = wire 0, []  # Loc: (0, 1, 18)
+  %19 = wire 0, []  # Loc: (0, 1, 19)
+  %20 = lamp false, []  # Loc: (0, 1, 20)
+}
\ No newline at end of file
diff --git a/tests/test_expects/long_redstone_wire_with_comparator_OPTIMIZED b/tests/test_expects/long_redstone_wire_with_comparator_OPTIMIZED
new file mode 100644
index 00000000..0cdbfed0
--- /dev/null
+++ b/tests/test_expects/long_redstone_wire_with_comparator_OPTIMIZED
@@ -0,0 +1,3 @@
+circuit {
+  %0 = lever false  # Loc: (0, 1, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/long_redstone_wire_with_comparator_UNOPTIMIZED b/tests/test_expects/long_redstone_wire_with_comparator_UNOPTIMIZED
new file mode 100644
index 00000000..6c5de5d3
--- /dev/null
+++ b/tests/test_expects/long_redstone_wire_with_comparator_UNOPTIMIZED
@@ -0,0 +1,18 @@
+circuit {
+  %0 = lever false  # Loc: (0, 1, 0)
+  %1 = wire 0, [%0:0]  # Loc: (0, 1, 1)
+  %2 = wire 0, [%0:1]  # Loc: (0, 1, 2)
+  %3 = wire 0, [%0:2]  # Loc: (0, 1, 3)
+  %4 = wire 0, [%0:3]  # Loc: (0, 1, 4)
+  %5 = wire 0, [%0:4]  # Loc: (0, 1, 5)
+  %6 = wire 0, [%0:5]  # Loc: (0, 1, 6)
+  %7 = wire 0, [%0:6]  # Loc: (0, 1, 7)
+  %8 = wire 0, [%0:7]  # Loc: (0, 1, 8)
+  %9 = wire 0, [%0:8]  # Loc: (0, 1, 9)
+  %10 = comparator compare, none, false, 0, [%0:8], []  # Loc: (0, 1, 10)
+  %11 = wire 0, [%10:0]  # Loc: (0, 1, 11)
+  %12 = wire 0, [%10:1]  # Loc: (0, 1, 12)
+  %13 = wire 0, [%10:2]  # Loc: (0, 1, 13)
+  %14 = wire 0, [%10:3]  # Loc: (0, 1, 14)
+  %15 = wire 0, [%10:4]  # Loc: (0, 1, 15)
+}
\ No newline at end of file
diff --git a/tests/test_expects/multiple_different_constants_OPTIMIZED b/tests/test_expects/multiple_different_constants_OPTIMIZED
new file mode 100644
index 00000000..d56ff8df
--- /dev/null
+++ b/tests/test_expects/multiple_different_constants_OPTIMIZED
@@ -0,0 +1,6 @@
+circuit {
+  %2 = lamp false, [%3:0]  # Loc: (4, 1, 0)
+  %3 = comparator subtract, none, false, 0, [%4:0], [%5:1, %5:3]  # Loc: (4, 1, 1)
+  %4 = lever false  # Loc: (4, 1, 2)
+  %5 = constant 15
+}
\ No newline at end of file
diff --git a/tests/test_expects/multiple_different_constants_UNOPTIMIZED b/tests/test_expects/multiple_different_constants_UNOPTIMIZED
new file mode 100644
index 00000000..e7419434
--- /dev/null
+++ b/tests/test_expects/multiple_different_constants_UNOPTIMIZED
@@ -0,0 +1,11 @@
+circuit {
+  %0 = constant 15  # Loc: (0, 1, 0)
+  %1 = wire 0, [%3:2, %0:0]  # Loc: (0, 1, 1)
+  %2 = wire 0, [%0:1, %3:1]  # Loc: (1, 1, 1)
+  %3 = constant 15  # Loc: (2, 1, 0)
+  %4 = wire 0, [%0:2, %3:0]  # Loc: (2, 1, 1)
+  %5 = wire 0, [%0:3, %3:1]  # Loc: (3, 1, 1)
+  %6 = lamp false, [%7:0]  # Loc: (4, 1, 0)
+  %7 = comparator subtract, none, false, 0, [%8:0], [%0:3, %3:1]  # Loc: (4, 1, 1)
+  %8 = lever false  # Loc: (4, 1, 2)
+}
\ No newline at end of file
diff --git a/tests/test_expects/repeater_chain_with_pending_update_OPTIMIZED b/tests/test_expects/repeater_chain_with_pending_update_OPTIMIZED
new file mode 100644
index 00000000..40d6f5ce
--- /dev/null
+++ b/tests/test_expects/repeater_chain_with_pending_update_OPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %1 = constant 15
+  %3 = lamp false, [%1:0]  # Loc: (3, 1, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/repeater_chain_with_pending_update_UNOPTIMIZED b/tests/test_expects/repeater_chain_with_pending_update_UNOPTIMIZED
new file mode 100644
index 00000000..c17f8d87
--- /dev/null
+++ b/tests/test_expects/repeater_chain_with_pending_update_UNOPTIMIZED
@@ -0,0 +1,6 @@
+circuit {
+  %0 = constant 15  # Loc: (0, 1, 0)
+  %1 = repeater 1, true, false, false, [%0:0], []  # Loc: (1, 1, 0)
+  %2 = repeater 1, false, false, false, [%1:0], []  # Loc: (2, 1, 0)
+  %3 = lamp false, [%2:0]  # Loc: (3, 1, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/repeater_clock_duplicated_repeaters_OPTIMIZED b/tests/test_expects/repeater_clock_duplicated_repeaters_OPTIMIZED
new file mode 100644
index 00000000..011bcdef
--- /dev/null
+++ b/tests/test_expects/repeater_clock_duplicated_repeaters_OPTIMIZED
@@ -0,0 +1,10 @@
+circuit {
+  %0 = lamp false, [%4:2, %3:1, %2:0]  # Loc: (0, 0, 2)
+  %1 = lever false  # Loc: (0, 1, 0)
+  %2 = repeater 1, false, false, false, [%7:5, %6:4, %5:3, %1:0], []  # Loc: (1, 1, 1)
+  %3 = repeater 1, false, false, false, [%7:4, %6:3, %5:2, %1:1], []  # Loc: (2, 1, 1)
+  %4 = repeater 1, false, false, false, [%7:3, %1:2, %6:2, %5:1], []  # Loc: (3, 1, 1)
+  %5 = repeater 1, false, false, false, [%2:3, %3:2, %4:1], []  # Loc: (4, 1, 1)
+  %6 = repeater 1, false, false, false, [%2:4, %3:3, %4:2], []  # Loc: (5, 1, 1)
+  %7 = repeater 1, false, false, false, [%2:5, %3:4, %4:3], []  # Loc: (6, 1, 1)
+}
\ No newline at end of file
diff --git a/tests/test_expects/repeater_clock_duplicated_repeaters_UNOPTIMIZED b/tests/test_expects/repeater_clock_duplicated_repeaters_UNOPTIMIZED
new file mode 100644
index 00000000..1b308cba
--- /dev/null
+++ b/tests/test_expects/repeater_clock_duplicated_repeaters_UNOPTIMIZED
@@ -0,0 +1,22 @@
+circuit {
+  %0 = lamp false, [%9:2, %6:1, %3:0]  # Loc: (0, 0, 2)
+  %1 = lever false  # Loc: (0, 1, 0)
+  %2 = wire 0, [%18:5, %15:4, %12:3, %1:0]  # Loc: (1, 1, 0)
+  %3 = repeater 1, false, false, false, [%18:5, %15:4, %12:3, %1:0], []  # Loc: (1, 1, 1)
+  %4 = wire 0, [%9:2, %6:1, %3:0]  # Loc: (1, 1, 2)
+  %5 = wire 0, [%18:4, %15:3, %12:2, %1:1]  # Loc: (2, 1, 0)
+  %6 = repeater 1, false, false, false, [%18:4, %15:3, %12:2, %1:1], []  # Loc: (2, 1, 1)
+  %7 = wire 0, [%3:1, %9:1, %6:0]  # Loc: (2, 1, 2)
+  %8 = wire 0, [%18:3, %1:2, %15:2, %12:1]  # Loc: (3, 1, 0)
+  %9 = repeater 1, false, false, false, [%18:3, %1:2, %15:2, %12:1], []  # Loc: (3, 1, 1)
+  %10 = wire 0, [%3:2, %6:1, %9:0]  # Loc: (3, 1, 2)
+  %11 = wire 0, [%1:3, %18:2, %15:1, %12:0]  # Loc: (4, 1, 0)
+  %12 = repeater 1, false, false, false, [%3:3, %6:2, %9:1], []  # Loc: (4, 1, 1)
+  %13 = wire 0, [%3:3, %6:2, %9:1]  # Loc: (4, 1, 2)
+  %14 = wire 0, [%1:4, %12:1, %18:1, %15:0]  # Loc: (5, 1, 0)
+  %15 = repeater 1, false, false, false, [%3:4, %6:3, %9:2], []  # Loc: (5, 1, 1)
+  %16 = wire 0, [%3:4, %6:3, %9:2]  # Loc: (5, 1, 2)
+  %17 = wire 0, [%1:5, %12:2, %15:1, %18:0]  # Loc: (6, 1, 0)
+  %18 = repeater 1, false, false, false, [%3:5, %6:4, %9:3], []  # Loc: (6, 1, 1)
+  %19 = wire 0, [%3:5, %6:4, %9:3]  # Loc: (6, 1, 2)
+}
\ No newline at end of file
diff --git a/tests/test_expects/unlit_torch_on_redstone_block_OPTIMIZED b/tests/test_expects/unlit_torch_on_redstone_block_OPTIMIZED
new file mode 100644
index 00000000..ac3be816
--- /dev/null
+++ b/tests/test_expects/unlit_torch_on_redstone_block_OPTIMIZED
@@ -0,0 +1,3 @@
+circuit {
+  %2 = lamp false, []  # Loc: (0, 2, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/unlit_torch_on_redstone_block_UNOPTIMIZED b/tests/test_expects/unlit_torch_on_redstone_block_UNOPTIMIZED
new file mode 100644
index 00000000..a496404e
--- /dev/null
+++ b/tests/test_expects/unlit_torch_on_redstone_block_UNOPTIMIZED
@@ -0,0 +1,5 @@
+circuit {
+  %0 = constant 15  # Loc: (0, 0, 0)
+  %1 = torch false, [%0:0]  # Loc: (0, 1, 0)
+  %2 = lamp false, [%1:0]  # Loc: (0, 2, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/unpowered_repeater_clock_OPTIMIZED b/tests/test_expects/unpowered_repeater_clock_OPTIMIZED
new file mode 100644
index 00000000..c2d3ecb4
--- /dev/null
+++ b/tests/test_expects/unpowered_repeater_clock_OPTIMIZED
@@ -0,0 +1,4 @@
+circuit {
+  %1 = lamp false, []  # Loc: (0, 1, 2)
+  %2 = lamp false, []  # Loc: (1, 1, 0)
+}
\ No newline at end of file
diff --git a/tests/test_expects/unpowered_repeater_clock_UNOPTIMIZED b/tests/test_expects/unpowered_repeater_clock_UNOPTIMIZED
new file mode 100644
index 00000000..ef4482f4
--- /dev/null
+++ b/tests/test_expects/unpowered_repeater_clock_UNOPTIMIZED
@@ -0,0 +1,8 @@
+circuit {
+  %0 = wire 0, []  # Loc: (0, 1, 0)
+  %1 = repeater 1, false, false, false, [], []  # Loc: (0, 1, 1)
+  %2 = lamp false, []  # Loc: (0, 1, 2)
+  %3 = lamp false, []  # Loc: (1, 1, 0)
+  %4 = repeater 1, false, false, false, [], []  # Loc: (1, 1, 1)
+  %5 = wire 0, []  # Loc: (1, 1, 2)
+}
\ No newline at end of file