diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
new file mode 100644
index 0000000..6f6325f
--- /dev/null
+++ b/.pre-commit-config.yaml
@@ -0,0 +1,21 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.5.0
+    hooks:
+      - id: end-of-file-fixer
+      - id: check-case-conflict
+      - id: check-executables-have-shebangs
+      - id: check-added-large-files
+      - id: check-case-conflict
+      - id: check-toml
+      - id: check-yaml
+      - id: debug-statements
+      - id: check-builtin-literals
+      - id: trailing-whitespace
+      - id: check-merge-conflict
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.2.0
+    hooks:
+     - id: ruff
+       args: ["--fix"]
+     - id: ruff-format
diff --git a/README.md b/README.md
index 5fc507b..1e36165 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,24 @@
-# ipython-markdown-inspector
\ No newline at end of file
+# ipython-markdown-inspector
+
+
+## Installation
+
+```
+pip install ipython-markdown-inspector
+```
+
+## Usage
+
+To load an extension while IPython is running, use the `%load_ext` magic:
+
+```
+%load_ext ipython_markdown_inspector
+```
+
+To load it each time IPython starts, list it in your [configuration file](https://ipython.readthedocs.io/en/stable/config/intro.html):
+
+```python
+c.InteractiveShellApp.extensions = [
+    'ipython_markdown_inspector'
+]
+```
diff --git a/ipython_markdown_inspector/__init__.py b/ipython_markdown_inspector/__init__.py
new file mode 100644
index 0000000..6dc747e
--- /dev/null
+++ b/ipython_markdown_inspector/__init__.py
@@ -0,0 +1,53 @@
+from functools import partial
+from typing import Any, Optional, Union
+
+from IPython.core.interactiveshell import InteractiveShell
+from IPython.core.oinspect import OInfo
+
+from ._hook_data import InspectorHookData
+from .formatter import as_markdown
+
+
+def hook(
+    obj_or_data: Union[InspectorHookData, Any],
+    info: Optional[OInfo] = None,
+    *_,
+    ipython: InteractiveShell,
+) -> str:
+    if isinstance(obj_or_data, InspectorHookData):
+        data = obj_or_data
+    else:
+        # fallback for IPython 8.21
+        obj = obj_or_data
+        detail_level = 0
+        omit_sections = []
+        info_dict = ipython.inspector.info(
+            obj, "", info=info, detail_level=detail_level
+        )
+        data = InspectorHookData(
+            obj=obj,
+            info=info,
+            info_dict=info_dict,
+            detail_level=detail_level,
+            omit_sections=omit_sections,
+        )
+    return as_markdown(data)
+
+
+ORIGINAL_HOOK = None
+
+
+def load_ipython_extension(ipython: InteractiveShell):
+    global ORIGINAL_HOOK
+    ORIGINAL_HOOK = ipython.inspector.mime_hooks.get("text/markdown", None)
+    ipython.inspector.mime_hooks["text/markdown"] = partial(hook, ipython=ipython)
+
+
+def unload_ipython_extension(ipython: InteractiveShell):
+    if ORIGINAL_HOOK is None:
+        del ipython.inspector.mime_hooks["text/markdown"]
+    else:
+        ipython.inspector.mime_hooks["text/markdown"] = ORIGINAL_HOOK
+
+
+__all__ = []
diff --git a/ipython_markdown_inspector/_hook_data.py b/ipython_markdown_inspector/_hook_data.py
new file mode 100644
index 0000000..156001a
--- /dev/null
+++ b/ipython_markdown_inspector/_hook_data.py
@@ -0,0 +1,9 @@
+try:
+    from IPython.core.oinspect import InspectorHookData
+except ImportError:
+    # TODO: remove once we require a version which includes
+    # https://github.com/ipython/ipython/pull/14342
+    from ._ipython_patch import InspectorHookData
+
+
+__all__ = ["InspectorHookData"]
diff --git a/ipython_markdown_inspector/_ipython_patch.py b/ipython_markdown_inspector/_ipython_patch.py
new file mode 100644
index 0000000..3391098
--- /dev/null
+++ b/ipython_markdown_inspector/_ipython_patch.py
@@ -0,0 +1,40 @@
+from typing import Any, TypedDict, Optional
+from dataclasses import dataclass
+
+from IPython.core.oinspect import OInfo
+
+
+class InfoDict(TypedDict):
+    type_name: Optional[str]
+    base_class: Optional[str]
+    string_form: Optional[str]
+    namespace: Optional[str]
+    length: Optional[str]
+    file: Optional[str]
+    definition: Optional[str]
+    docstring: Optional[str]
+    source: Optional[str]
+    init_definition: Optional[str]
+    class_docstring: Optional[str]
+    init_docstring: Optional[str]
+    call_def: Optional[str]
+    call_docstring: Optional[str]
+    subclasses: Optional[str]
+    # These won't be printed but will be used to determine how to
+    # format the object
+    ismagic: bool
+    isalias: bool
+    isclass: bool
+    found: bool
+    name: str
+
+
+@dataclass
+class InspectorHookData:
+    """Data passed to the mime hook"""
+
+    obj: Any
+    info: Optional[OInfo]
+    info_dict: InfoDict
+    detail_level: int
+    omit_sections: list[str]
diff --git a/ipython_markdown_inspector/formatter.py b/ipython_markdown_inspector/formatter.py
new file mode 100644
index 0000000..f79ec08
--- /dev/null
+++ b/ipython_markdown_inspector/formatter.py
@@ -0,0 +1,104 @@
+from typing import Dict, List
+
+import docstring_to_markdown
+from IPython.core.oinspect import is_simple_callable
+
+from ._hook_data import InspectorHookData
+from .models import Field, CodeField, DocField, RowField
+
+
+FIELDS: Dict[str, List[Field]] = {
+    "alias": [
+        CodeField(label="Repr", key="string_form"),
+    ],
+    "magic": [
+        DocField(label="Docstring", key="docstring"),
+        CodeField(label="Source", key="source", min_level=1),
+        RowField(label="File", key="file"),
+    ],
+    "class_or_callable": [
+        # Functions, methods, classes
+        CodeField(label="Signature", key="definition"),
+        CodeField(label="Init signature", key="init_definition"),
+        DocField(label="Docstring", key="docstring"),
+        CodeField(label="Source", key="source", min_level=1),
+        DocField(label="Init docstring", key="init_docstring"),
+        RowField(label="File", key="file"),
+        RowField(label="Type", key="type_name"),
+        RowField(label="Subclasses", key="subclasses"),
+    ],
+    "default": [
+        # General Python objects
+        CodeField(label="Signature", key="definition"),
+        CodeField(label="Call signature", key="call_def"),
+        RowField(label="Type", key="type_name"),
+        RowField(label="String form", key="string_form"),
+        RowField(label="Namespace", key="namespace"),
+        RowField(label="Length", key="length"),
+        RowField(label="File", key="file"),
+        DocField(label="Docstring", key="docstring"),
+        CodeField(label="Source", key="source", min_level=1),
+        DocField(label="Class docstring", key="class_docstring"),
+        DocField(label="Init docstring", key="init_docstring"),
+        DocField(label="Call docstring", key="call_docstring"),
+    ],
+}
+
+
+TABLE_STARTER = """\
+| <!-- --> | <!-- --> |
+|----------|----------|\
+"""
+
+
+def markdown_formatter(text: str):
+    try:
+        converted = docstring_to_markdown.convert(text)
+        return converted
+    except docstring_to_markdown.UnknownFormatError:
+        return f"<pre>{text}</pre>"
+
+
+def code_formatter(code, language="python"):
+    return f"```{language}\n{code}\n```"
+
+
+def as_markdown(data: InspectorHookData) -> str:
+    if data.info and not data.info.found:
+        return str(data.info)
+
+    info_dict = data.info_dict
+
+    if info_dict["namespace"] == "Interactive":
+        info_dict["namespace"] = None
+
+    # TODO: maybe remove docstring from source?
+    # info_dict["source"] = remove_docstring(source)
+
+    if info_dict["isalias"]:
+        fields = FIELDS["alias"]
+    elif info_dict["ismagic"]:
+        fields = FIELDS["magic"]
+    if info_dict["isclass"] or is_simple_callable(data.obj):
+        fields = FIELDS["class_or_callable"]
+    else:
+        fields = FIELDS["default"]
+
+    chunks = []
+
+    in_table = False
+    for field in fields:
+        value = info_dict.get(field.key)
+        if value is None:
+            continue
+        if field.kind == "row":
+            if not in_table:
+                in_table = True
+                chunks.append(TABLE_STARTER)
+            chunks[-1] += f"\n| {field.label} | `{value}` |"
+        if field.kind == "code":
+            chunks.append(f"#### {field.label}\n\n" + code_formatter(value))
+        if field.kind == "doc":
+            chunks.append(f"#### {field.label}\n\n" + markdown_formatter(value))
+
+    return "\n\n".join(chunks)
diff --git a/ipython_markdown_inspector/models.py b/ipython_markdown_inspector/models.py
new file mode 100644
index 0000000..1f50d90
--- /dev/null
+++ b/ipython_markdown_inspector/models.py
@@ -0,0 +1,25 @@
+from dataclasses import dataclass
+from typing import Literal
+
+
+@dataclass
+class Field:
+    key: str
+    label: str
+    kind: str
+    min_level: int = 0
+
+
+@dataclass
+class RowField(Field):
+    kind: Literal["row"] = "row"
+
+
+@dataclass
+class CodeField(Field):
+    kind: Literal["code"] = "code"
+
+
+@dataclass
+class DocField(Field):
+    kind: Literal["doc"] = "doc"
diff --git a/ipython_markdown_inspector/tests/test_as_markdown.py b/ipython_markdown_inspector/tests/test_as_markdown.py
new file mode 100644
index 0000000..f5198cd
--- /dev/null
+++ b/ipython_markdown_inspector/tests/test_as_markdown.py
@@ -0,0 +1,50 @@
+from IPython.core.interactiveshell import InteractiveShell
+from IPython import get_ipython
+import pytest
+
+from ipython_markdown_inspector.formatter import as_markdown
+from ipython_markdown_inspector._hook_data import InspectorHookData
+
+
+def simple_func(arg):
+    """Calls :py:func:`bool` on ``arg``"""
+    return bool(arg)
+
+
+class SimpleClass:
+    pass
+
+
+@pytest.mark.parametrize(
+    "object_name, part",
+    [
+        ["%%python", "Run cells with python"],
+        ["simple_func", "Calls `bool` on ``arg``"],
+        ["simple_func", "| Type | `function` |"],
+        ["test_int", "| Type | `int` |"],
+        ["test_int", "| String form | `1` |"],
+        ["test_str", "| Type | `str` |"],
+        ["test_str", "| String form | `a` |"],
+        ["test_str", "| Length | `1` |"],
+        ["simple_cls", "| Type | `type` |"],
+        ["simple_instance", "| Type | `SimpleClass` |"],
+    ],
+)
+def test_result_contains(object_name, part):
+    ip: InteractiveShell = get_ipython()  # type: ignore
+    ip.user_ns["test_str"] = "a"
+    ip.user_ns["test_int"] = 1
+    ip.user_ns["simple_func"] = simple_func
+    ip.user_ns["simple_cls"] = SimpleClass
+    ip.user_ns["simple_instance"] = SimpleClass()
+    oinfo = ip._object_find(object_name)
+    detail_level = 0
+    info_dict = ip.inspector.info(oinfo.obj, object_name)
+    data = InspectorHookData(
+        obj=oinfo.obj,
+        info=oinfo,
+        info_dict=info_dict,
+        detail_level=detail_level,
+        omit_sections=[],
+    )
+    assert part in as_markdown(data)
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..7113fda
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,45 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "ipython-markdown-inspector"
+version = "0.0.0"
+dependencies = [
+  "ipython>=8.21.0",
+  "docstring-to-markdown>=0.13,<1.0"
+]
+requires-python = ">=3.8"
+authors = [
+  {name = "Michał Krassowski"}
+]
+description = ""
+readme = "README.md"
+license = {file = "LICENSE"}
+keywords = ["IPython", "markdown", "inpsector", "docstring"]
+classifiers = [
+  "Framework :: IPython",
+  "Framework :: Jupyter",
+  "Development Status :: 4 - Beta",
+  "Intended Audience :: Developers",
+  "Intended Audience :: Science/Research",
+  "License :: OSI Approved :: BSD License",
+  "Programming Language :: Python",
+  "Programming Language :: Python :: 3",
+  "Programming Language :: Python :: 3 :: Only",
+]
+
+[project.urls]
+Repository = "https://github.com/krassowski/ipython-markdown-inspector.git"
+"Bug Tracker" = "https://github.com/krassowski/ipython-markdown-inspector/issues"
+Changelog = "https://github.com/krassowski/ipython-markdown-inspector/blob/main/CHANGELOG.md"
+
+[project.optional-dependencies]
+test = [
+    "pytest"
+]
+dev = [
+    "build",
+    "pre-commit",
+    "ruff==0.2.0"
+]