diff --git a/justfile b/justfile
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+# Justfile for Sandcage
+#
+# Environment variables are loaded from `.env` automatically.
+set shell := ["sh", "-cu"]
+set windows-shell := ["sh", "-cu"]
+set dotenv-load := true
+
+export PYTHONIOENCODING := "utf-8"
+
+# Default: list available recipes.
+default:
+    @just --list
+
+# Run cargo check.
+check:
+    cargo check
+
+# Run cargo build.
+build:
+    cargo build
+
+# Run tests.
+test:
+    cargo test
+
+# Run Claude Code.
+claude:
+    claude --allow-dangerously-skip-permissions
+
+# Export to public repo (force-with-lease push to main).
+export *FLAGS:
+    uv run python scripts/export.py push {{FLAGS}}
+
+# Dry-run export (inspect without pushing).
+export-dry:
+    uv run python scripts/export.py push --dry-run