diff --git a/README2.md b/README2.md
index 2e192b5..93c81dc 100644
--- a/README2.md
+++ b/README2.md
@@ -271,3 +271,9 @@ cargo test
 # Build release
 cargo build --release --features gui
 ```
+
+## Reviewing And Contributing
+
+- See `AGENTS.md` for repository-specific coding guidance.
+- See `REVIEWING.md` for a reviewer-oriented map of the codebase and recommended commands.
+- If you have `just` installed, run `just --list` for common review and validation commands.
diff --git a/REVIEWING.md b/REVIEWING.md
new file mode 100644
index 0000000..e7b0b47
--- /dev/null
+++ b/REVIEWING.md
@@ -0,0 +1,163 @@
+# Reviewing Geolog
+
+This guide is for humans reviewing the codebase, especially when you want to answer:
+
+- where a behavior lives,
+- which commands to run first,
+- and which modules are most likely to matter for a given bug or change.
+
+## Quick Start
+
+If you have `just` installed:
+
+```bash
+just review
+just review-gui
+```
+
+Without `just`:
+
+```bash
+cargo check
+cargo test
+cargo check --features gui --bin geolog-gui
+cargo test --features gui
+```
+
+## Best Reading Order
+
+For most reviews, this order gives the fastest mental model:
+
+1. `README.md`
+   - User-facing behavior and examples.
+2. `docs/ARCHITECTURE.md`
+   - High-level subsystem map.
+3. `src/lib.rs`
+   - Top-level module layout.
+4. Syntax pipeline
+   - `src/ast.rs`
+   - `src/lexer.rs`
+   - `src/parser.rs`
+   - `src/pretty.rs`
+5. Semantic core
+   - `src/core.rs`
+   - `src/id.rs`
+   - `src/universe.rs`
+6. Elaboration
+   - `src/elaborate/mod.rs`
+   - `src/elaborate/theory.rs`
+   - `src/elaborate/instance.rs`
+7. Runtime and persistence
+   - `src/repl.rs`
+   - `src/store/mod.rs`
+   - `src/store/theory.rs`
+   - `src/store/instance.rs`
+8. Query and chase
+   - `src/query/mod.rs`
+   - `src/query/chase.rs`
+   - `src/query/compile.rs`
+   - `src/query/backend.rs`
+9. Optional layers
+   - `src/solver/`
+   - `src/gui/`
+
+## How To Map A Change
+
+Use this shortcut table:
+
+- Parse error or syntax ambiguity
+  - Start in `src/lexer.rs` and `src/parser.rs`.
+- Pretty-print or round-trip bug
+  - Start in `src/pretty.rs`, then `tests/unit_pretty.rs` and `tests/unit_parsing.rs`.
+- Wrong theory or instance semantics
+  - Start in `src/elaborate/` and `src/core.rs`.
+- Persistence or workspace bug
+  - Start in `src/repl.rs` and `src/store/`.
+- Chase/query behavior bug
+  - Start in `src/query/chase.rs`, `src/query/compile.rs`, and related tests.
+- GUI-only behavior bug
+  - Start in `src/gui/state.rs`, then `src/gui/panels/` or `src/gui/visualizations/`.
+
+## Important Invariants
+
+- `parser` should stay syntax-focused.
+  - Semantic decisions generally belong in elaboration, not parsing.
+- `core` should remain GUI-free.
+  - GUI code should consume existing semantics, not define them.
+- GUI must remain feature-gated.
+  - GUI code lives behind the `gui` feature.
+- Persistence changes need extra care.
+  - `src/store/` and related runtime flows should preserve expected workspace behavior.
+- Chase/query changes need explicit tests.
+  - These regressions are often subtle and easy to miss in manual review.
+
+## Best Review Commands
+
+Start narrow, then go broad.
+
+### Core checks
+
+```bash
+cargo check
+cargo test
+```
+
+### GUI checks
+
+```bash
+cargo check --features gui --bin geolog-gui
+cargo test --features gui
+```
+
+### Focused checks
+
+```bash
+cargo test unit_parsing
+cargo test unit_elaborate
+cargo test unit_chase
+cargo test unit_workspace
+cargo test gui_
+```
+
+## Test File Guide
+
+- `tests/unit_parsing.rs`
+  - Parser and syntax behavior.
+- `tests/unit_pretty.rs`
+  - Pretty-printing and round-trip expectations.
+- `tests/unit_elaborate.rs`
+  - Theory/instance elaboration semantics.
+- `tests/unit_chase.rs`
+  - Chase behavior.
+- `tests/unit_workspace.rs`
+  - Persistence/workspace behavior.
+- `tests/examples_integration.rs`
+  - End-to-end examples.
+- `tests/proptest_*.rs`
+  - Property-based coverage.
+
+## What Usually Deserves Extra Scrutiny
+
+- Changes that cross parser → elaboration boundaries.
+- Changes in `src/core.rs` because they affect many layers.
+- Anything in `src/query/chase.rs`, `src/query/backend.rs`, or `src/store/`.
+- GUI changes that mutate runtime state rather than only presenting it.
+- Feature-gated code that may compile less often than the default build.
+
+## Useful Missing Context To Watch For
+
+If a patch is hard to review, it often needs one of these:
+
+- a smaller regression test,
+- a more focused example in `examples/geolog/`,
+- a note in `docs/ARCHITECTURE.md`,
+- or a short comment explaining a non-obvious invariant.
+
+## Reviewer Checklist
+
+- Does the change live in the right layer?
+- Are semantics changed intentionally, or just presentation?
+- Is there a narrow test for the bug or behavior?
+- If GUI code changed, is the same state transition safe from the REPL path too?
+- If store/query/chase code changed, do existing tests still cover the affected behavior?
+- Is any documentation now stale?
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..c907ce6
--- /dev/null
+++ b/justfile
@@ -0,0 +1,42 @@
+set shell := ["bash", "-lc"]
+
+default:
+	@just --list
+
+check:
+	cargo check
+
+test:
+	cargo test
+
+gui-check:
+	cargo check --features gui --bin geolog-gui
+
+gui-test:
+	cargo test --features gui
+
+review:
+	cargo check
+	cargo test
+
+review-gui:
+	cargo check --features gui --bin geolog-gui
+	cargo test --features gui
+
+focus-parsing:
+	cargo test unit_parsing
+
+focus-elaborate:
+	cargo test unit_elaborate
+
+focus-chase:
+	cargo test unit_chase
+
+focus-workspace:
+	cargo test unit_workspace
+
+focus-gui:
+	cargo test --features gui gui_
+
+test-one NAME:
+	cargo test {{NAME}}