diff --git a/.github/workflows/system.yml b/.github/workflows/system.yml
index 6cf32af..9e76a52 100644
--- a/.github/workflows/system.yml
+++ b/.github/workflows/system.yml
@@ -6,7 +6,8 @@ on:
     branches: [main]
 
 jobs:
-  system:
+  system-full:
+    name: Test Full Installation
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
@@ -16,8 +17,8 @@ jobs:
         run: uv venv --python 3.12
       - name: Set up Docker
         uses: docker/setup-buildx-action@v3
-      - name: Install the project
-        run: uv sync
+      - name: Install the project (full)
+        run: uv pip install -e .
       - name: Set up commit0
         run: uv run commit0 setup simpy
       - name: Build docker images
@@ -45,3 +46,39 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.MY_GITHUB_TOKEN }}
         run: |
           uv run commit0 save test-save-commit0 master
+
+  system-core:
+    name: Test Core Installation
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install uv
+        uses: astral-sh/setup-uv@v2
+      - name: Set up Python
+        run: uv venv --python 3.12
+      - name: Set up Docker
+        uses: docker/setup-buildx-action@v3
+      - name: Install the project (core)
+        run: uv pip install -e .[core]
+      - name: Set up commit0
+        run: uv run commit0 setup simpy
+      - name: Build docker images
+        run: uv run commit0 build
+      - name: Get tests
+        run: uv run commit0 get-tests simpy
+      - name: Test
+        env:
+          MODAL_TOKEN_ID: ${{secrets.MODAL_TOKEN_ID}}
+          MODAL_TOKEN_SECRET: ${{secrets.MODAL_TOKEN_SECRET}}
+        run: |
+          uv run commit0 test simpy tests/test_event.py::test_succeed --reference --rebuild
+          uv run commit0 test simpy tests/test_event.py::test_succeed --reference
+      - name: Evaluate
+        env:
+          MODAL_TOKEN_ID: ${{secrets.MODAL_TOKEN_ID}}
+          MODAL_TOKEN_SECRET: ${{secrets.MODAL_TOKEN_SECRET}}
+        run: |
+          uv run commit0 evaluate --reference  --rebuild
+          uv run commit0 evaluate --reference
+      - name: Lint
+        run: uv run commit0 lint commit0/harness/
diff --git a/build.py b/build.py
new file mode 100644
index 0000000..95dcd2d
--- /dev/null
+++ b/build.py
@@ -0,0 +1,18 @@
+from hatchling.builders.hooks.plugin.interface import BuildHookInterface
+
+
+class CustomBuildHook(BuildHookInterface):
+    def initialize(self, version: str, build_data: dict) -> None:
+        """Add agent package if not installing core-only."""
+        # Handle both wheel and editable builds
+        for build_type in ["wheel", "editable"]:
+            if build_type not in build_data:
+                continue
+
+            for target in build_data[build_type].get("targets", []):
+                extras = target.get("options", {}).get("extras", [])
+                packages = target.get("packages", [])
+
+                if "core" not in extras and "commit0.optional.agent" not in packages:
+                    packages.append("commit0.optional.agent")
+                    target["packages"] = packages
diff --git a/commit0/commit0 b/commit0/commit0
new file mode 160000
index 0000000..a853f81
--- /dev/null
+++ b/commit0/commit0
@@ -0,0 +1 @@
+Subproject commit a853f8168dc8187eebbd788c8fc4a4137644f74b
diff --git a/commit0/optional/__init__.py b/commit0/optional/__init__.py
new file mode 100644
index 0000000..8ab3a79
--- /dev/null
+++ b/commit0/optional/__init__.py
@@ -0,0 +1 @@
+"""Optional packages for commit0."""
diff --git a/agent/README.md b/commit0/optional/agent/README.md
similarity index 100%
rename from agent/README.md
rename to commit0/optional/agent/README.md
diff --git a/agent/__main__.py b/commit0/optional/agent/__main__.py
similarity index 70%
rename from agent/__main__.py
rename to commit0/optional/agent/__main__.py
index e2bc954..99522f8 100644
--- a/agent/__main__.py
+++ b/commit0/optional/agent/__main__.py
@@ -1,4 +1,4 @@
-from agent.cli import agent_app
+from commit0.optional.agent.cli import agent_app
 
 
 def main() -> None:
diff --git a/agent/agent_utils.py b/commit0/optional/agent/agent_utils.py
similarity index 99%
rename from agent/agent_utils.py
rename to commit0/optional/agent/agent_utils.py
index 4fdea82..b123cf0 100644
--- a/agent/agent_utils.py
+++ b/commit0/optional/agent/agent_utils.py
@@ -10,7 +10,7 @@
 from graphlib import TopologicalSorter, CycleError
 import yaml
 
-from agent.class_types import AgentConfig
+from commit0.optional.agent.class_types import AgentConfig
 
 PROMPT_HEADER = ">>> Here is the Task:\n"
 REFERENCE_HEADER = "\n\n>>> Here is the Reference for you to finish the task:\n"
diff --git a/agent/agents.py b/commit0/optional/agent/agents.py
similarity index 100%
rename from agent/agents.py
rename to commit0/optional/agent/agents.py
diff --git a/agent/class_types.py b/commit0/optional/agent/class_types.py
similarity index 100%
rename from agent/class_types.py
rename to commit0/optional/agent/class_types.py
diff --git a/agent/cli.py b/commit0/optional/agent/cli.py
similarity index 97%
rename from agent/cli.py
rename to commit0/optional/agent/cli.py
index b02bf7a..229b3e8 100644
--- a/agent/cli.py
+++ b/commit0/optional/agent/cli.py
@@ -1,9 +1,9 @@
 import typer
-from agent.run_agent_no_rich import run_agent as run_agent_no_rich
-from agent.run_agent import run_agent
+from commit0.optional.agent.run_agent_no_rich import run_agent as run_agent_no_rich
+from commit0.optional.agent.run_agent import run_agent
 from commit0.harness.constants import RUN_AGENT_LOG_DIR
 import subprocess
-from agent.agent_utils import write_agent_config
+from commit0.optional.agent.agent_utils import write_agent_config
 
 agent_app = typer.Typer(
     no_args_is_help=True,
diff --git a/agent/configs/agent.yaml b/commit0/optional/agent/configs/agent.yaml
similarity index 100%
rename from agent/configs/agent.yaml
rename to commit0/optional/agent/configs/agent.yaml
diff --git a/agent/configs/base.yaml b/commit0/optional/agent/configs/base.yaml
similarity index 100%
rename from agent/configs/base.yaml
rename to commit0/optional/agent/configs/base.yaml
diff --git a/agent/display.py b/commit0/optional/agent/display.py
similarity index 100%
rename from agent/display.py
rename to commit0/optional/agent/display.py
diff --git a/agent/run_agent.py b/commit0/optional/agent/run_agent.py
similarity index 98%
rename from agent/run_agent.py
rename to commit0/optional/agent/run_agent.py
index a1324cd..73d20cf 100644
--- a/agent/run_agent.py
+++ b/commit0/optional/agent/run_agent.py
@@ -3,7 +3,7 @@
 import multiprocessing
 from datasets import load_dataset
 from git import Repo
-from agent.agent_utils import (
+from commit0.optional.agent.agent_utils import (
     create_branch,
     get_message,
     get_target_edit_files,
@@ -14,17 +14,17 @@
 )
 import json
 import subprocess
-from agent.agents import AiderAgents
+from commit0.optional.agent.agents import AiderAgents
 from typing import Optional, Type, cast
 from types import TracebackType
-from agent.class_types import AgentConfig
+from commit0.optional.agent.class_types import AgentConfig
 from commit0.harness.constants import SPLIT
 from commit0.harness.get_pytest_ids import main as get_tests
 from commit0.harness.constants import RUN_AGENT_LOG_DIR, RepoInstance
 from commit0.cli import read_commit0_config_file
 from pathlib import Path
 from datetime import datetime
-from agent.display import TerminalDisplay
+from commit0.optional.agent.display import TerminalDisplay
 import queue
 import time
 
diff --git a/agent/run_agent_no_rich.py b/commit0/optional/agent/run_agent_no_rich.py
similarity index 97%
rename from agent/run_agent_no_rich.py
rename to commit0/optional/agent/run_agent_no_rich.py
index 5822063..f0a7753 100644
--- a/agent/run_agent_no_rich.py
+++ b/commit0/optional/agent/run_agent_no_rich.py
@@ -4,7 +4,7 @@
 from tqdm import tqdm
 from datasets import load_dataset
 from git import Repo
-from agent.agent_utils import (
+from commit0.optional.agent.agent_utils import (
     create_branch,
     get_message,
     get_target_edit_files,
@@ -15,16 +15,16 @@
 )
 import subprocess
 import json
-from agent.agents import AiderAgents
+from commit0.optional.agent.agents import AiderAgents
 from typing import cast
-from agent.class_types import AgentConfig
+from commit0.optional.agent.class_types import AgentConfig
 from commit0.harness.constants import SPLIT
 from commit0.harness.get_pytest_ids import main as get_tests
 from commit0.harness.constants import RUN_AGENT_LOG_DIR, RepoInstance
 from commit0.cli import read_commit0_config_file
 from pathlib import Path
 from datetime import datetime
-from agent.run_agent import DirContext, run_eval_after_each_commit
+from commit0.optional.agent.run_agent import DirContext, run_eval_after_each_commit
 
 
 def run_agent_for_repo(
diff --git a/pyproject.toml b/pyproject.toml
index 8aa376d..8f4f38d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ dependencies = [
     "pre-commit>=3.8.0",
     "import-deps>=0.3.0",
     "PyMuPDF>=1.24.5",
-    "modal==0.64.95",
+    "modal>=0.64.95",
     "typer>=0.12.0",
     "tenacity>=8.5.0",
     "docker>=7.1.0",
@@ -30,13 +30,29 @@ classifiers = [
 
 [project.scripts]
 commit0 = "commit0.__main__:main"
-agent = "agent.__main__:main"
 
 [tool.hatch.build.targets.wheel]
-packages = ["commit0", "agent"]
+packages = ["commit0"]
+
+[tool.hatch.build.targets.wheel.hooks.custom]
+path = "build.py"
 
 [project.optional-dependencies]
-agent = []
+core = [
+    "ruff>=0.6.4",
+    "pre-commit>=3.8.0",
+    "import-deps>=0.3.0",
+    "PyMuPDF>=1.24.5",
+    "modal>=0.64.95",
+    "typer>=0.12.0",
+    "tenacity>=8.5.0",
+    "docker>=7.1.0",
+    "fastcore>=1.7.8",
+    "ghapi>=1.0.6",
+    "gitpython>=3.1.43",
+    "pytest>=8.3.3",
+    "datasets==3.0.1",
+]
 
 [project.urls]
 Homepage = "https://commit-0.github.io/"
diff --git a/uv.lock b/uv.lock
index c2c4ed2..ad8fa07 100644
--- a/uv.lock
+++ b/uv.lock
@@ -367,7 +367,7 @@ wheels = [
 
 [[package]]
 name = "commit0"
-version = "0.1.4"
+version = "0.1.6"
 source = { editable = "." }
 dependencies = [
     { name = "aider-chat" },
@@ -376,6 +376,24 @@ dependencies = [
     { name = "fastcore" },
     { name = "ghapi" },
     { name = "gitpython" },
+    { name = "import-deps" },
+    { name = "modal" },
+    { name = "pre-commit" },
+    { name = "pymupdf" },
+    { name = "pytest" },
+    { name = "ruff" },
+    { name = "tenacity" },
+    { name = "typer" },
+]
+
+[package.optional-dependencies]
+core = [
+    { name = "datasets" },
+    { name = "docker" },
+    { name = "fastcore" },
+    { name = "ghapi" },
+    { name = "gitpython" },
+    { name = "import-deps" },
     { name = "modal" },
     { name = "pre-commit" },
     { name = "pymupdf" },
@@ -389,17 +407,31 @@ dependencies = [
 requires-dist = [
     { name = "aider-chat", git = "https://github.com/wenting-zhao/aider.git" },
     { name = "datasets", specifier = "==3.0.1" },
+    { name = "datasets", marker = "extra == 'core'", specifier = "==3.0.1" },
     { name = "docker", specifier = ">=7.1.0" },
+    { name = "docker", marker = "extra == 'core'", specifier = ">=7.1.0" },
     { name = "fastcore", specifier = ">=1.7.8" },
+    { name = "fastcore", marker = "extra == 'core'", specifier = ">=1.7.8" },
     { name = "ghapi", specifier = ">=1.0.6" },
+    { name = "ghapi", marker = "extra == 'core'", specifier = ">=1.0.6" },
     { name = "gitpython", specifier = ">=3.1.43" },
-    { name = "modal", specifier = "==0.64.95" },
+    { name = "gitpython", marker = "extra == 'core'", specifier = ">=3.1.43" },
+    { name = "import-deps", specifier = ">=0.3.0" },
+    { name = "import-deps", marker = "extra == 'core'", specifier = ">=0.3.0" },
+    { name = "modal", specifier = ">=0.64.95" },
+    { name = "modal", marker = "extra == 'core'", specifier = ">=0.64.95" },
     { name = "pre-commit", specifier = ">=3.8.0" },
+    { name = "pre-commit", marker = "extra == 'core'", specifier = ">=3.8.0" },
     { name = "pymupdf", specifier = ">=1.24.5" },
+    { name = "pymupdf", marker = "extra == 'core'", specifier = ">=1.24.5" },
     { name = "pytest", specifier = ">=8.3.3" },
+    { name = "pytest", marker = "extra == 'core'", specifier = ">=8.3.3" },
     { name = "ruff", specifier = ">=0.6.4" },
+    { name = "ruff", marker = "extra == 'core'", specifier = ">=0.6.4" },
     { name = "tenacity", specifier = ">=8.5.0" },
+    { name = "tenacity", marker = "extra == 'core'", specifier = ">=8.5.0" },
     { name = "typer", specifier = ">=0.12.0" },
+    { name = "typer", marker = "extra == 'core'", specifier = ">=0.12.0" },
 ]
 
 [[package]]
@@ -762,6 +794,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/76/c6/c88e154df9c4e1a2a66ccf0005a88dfb2650c1dffb6f5ce603dfbd452ce3/idna-3.10-py3-none-any.whl", hash = "sha256:946d195a0d259cbba61165e88e65941f16e9b36ea6ddb97f00452bae8b1287d3", size = 70442 },
 ]
 
+[[package]]
+name = "import-deps"
+version = "0.3.0"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/21/0c/487690243f9d792c7d1cfdcbc971e21b901140c367729ae83e17d08242ae/import_deps-0.3.0.tar.gz", hash = "sha256:542544c69a435517dc8e556d0030044f49f2e61fff11ab8c2c612ac56ff62705", size = 6624 }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/02/ea/8461a8fc157df724d56c7f0cce8d86af130bcb5e99622af2d3e6ceeca74f/import_deps-0.3.0-py3-none-any.whl", hash = "sha256:4619659d57b8d5426177de7b98748a04446dc756c18544d8d75afda33bb0b008", size = 7604 },
+]
+
 [[package]]
 name = "importlib-metadata"
 version = "7.2.1"
@@ -1040,7 +1081,11 @@ dependencies = [
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/68/e0/a77ca96e772e13c828fa52f3ad370d413bef194aeaf78b7c6611870ad815/multiprocess-0.70.15.tar.gz", hash = "sha256:f20eed3036c0ef477b07a4177cf7c1ba520d9a2677870a4f47fe026f0cd6787e", size = 1894495 }
 wheels = [
+    { url = "https://files.pythonhosted.org/packages/35/a8/36d8d7b3e46b377800d8dec47891cdf05842d1a2366909ae4a0c89fbc5e6/multiprocess-0.70.15-py310-none-any.whl", hash = "sha256:7dd58e33235e83cf09d625e55cffd7b0f0eede7ee9223cdd666a87624f60c21a", size = 134824 },
     { url = "https://files.pythonhosted.org/packages/e7/41/96ac938770ba6e7d5ae1d8c9cafebac54b413549042c6260f0d0a6ec6622/multiprocess-0.70.15-py311-none-any.whl", hash = "sha256:134f89053d82c9ed3b73edd3a2531eb791e602d4f4156fc92a79259590bd9670", size = 135392 },
+    { url = "https://files.pythonhosted.org/packages/ca/3f/8354ce12fd13bd5c5bb4722261a10ca1d6e2eb7c1c08fa3d8a4e9dc98f44/multiprocess-0.70.15-py37-none-any.whl", hash = "sha256:f7d4a1629bccb433114c3b4885f69eccc200994323c80f6feee73b0edc9199c5", size = 116276 },
+    { url = "https://files.pythonhosted.org/packages/c2/a6/c5cb599d917904878f220a4dbdfdcc4ef291dd3956c35b3b0dc6fc42fb6d/multiprocess-0.70.15-py38-none-any.whl", hash = "sha256:bee9afba476c91f9ebee7beeee0601face9eff67d822e893f9a893725fbd6316", size = 132626 },
+    { url = "https://files.pythonhosted.org/packages/c6/c9/820b5ab056f4ada76fbe05bd481a948f287957d6cbfd59e2dd2618b408c1/multiprocess-0.70.15-py39-none-any.whl", hash = "sha256:3e0953f5d52b4c76f1c973eaf8214554d146f2be5decb48e928e55c7a2d19338", size = 133349 },
 ]
 
 [[package]]
@@ -1282,8 +1327,6 @@ version = "6.0.0"
 source = { registry = "https://pypi.org/simple" }
 sdist = { url = "https://files.pythonhosted.org/packages/18/c7/8c6872f7372eb6a6b2e4708b88419fb46b857f7a2e1892966b851cc79fc9/psutil-6.0.0.tar.gz", hash = "sha256:8faae4f310b6d969fa26ca0545338b21f73c6b15db7c4a8d934a5482faa818f2", size = 508067 }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/c5/66/78c9c3020f573c58101dc43a44f6855d01bbbd747e24da2f0c4491200ea3/psutil-6.0.0-cp27-none-win32.whl", hash = "sha256:02b69001f44cc73c1c5279d02b30a817e339ceb258ad75997325e0e6169d8b35", size = 249766 },
-    { url = "https://files.pythonhosted.org/packages/e1/3f/2403aa9558bea4d3854b0e5e567bc3dd8e9fbc1fc4453c0aa9aafeb75467/psutil-6.0.0-cp27-none-win_amd64.whl", hash = "sha256:21f1fb635deccd510f69f485b87433460a603919b45e2a324ad65b0cc74f8fb1", size = 253024 },
     { url = "https://files.pythonhosted.org/packages/0b/37/f8da2fbd29690b3557cca414c1949f92162981920699cd62095a984983bf/psutil-6.0.0-cp36-abi3-macosx_10_9_x86_64.whl", hash = "sha256:c588a7e9b1173b6e866756dde596fd4cad94f9399daf99ad8c3258b3cb2b47a0", size = 250961 },
     { url = "https://files.pythonhosted.org/packages/35/56/72f86175e81c656a01c4401cd3b1c923f891b31fbcebe98985894176d7c9/psutil-6.0.0-cp36-abi3-manylinux_2_12_i686.manylinux2010_i686.manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:6ed2440ada7ef7d0d608f20ad89a04ec47d2d3ab7190896cd62ca5fc4fe08bf0", size = 287478 },
     { url = "https://files.pythonhosted.org/packages/19/74/f59e7e0d392bc1070e9a70e2f9190d652487ac115bb16e2eff6b22ad1d24/psutil-6.0.0-cp36-abi3-manylinux_2_12_x86_64.manylinux2010_x86_64.manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:5fd9a97c8e94059b0ef54a7d4baf13b405011176c3b6ff257c247cae0d560ecd", size = 290455 },