diff --git a/README.md b/README.md
index 90c79c9..a601698 100644
--- a/README.md
+++ b/README.md
@@ -42,6 +42,7 @@ Equally, the only thing flatnotes caches is the search index and that's incremen
 * Light/dark themes.
 * Multiple authentication options (none, read-only, username/password, 2FA).
 * Restful API.
+* Hook on create/update/delete.
 
 See [the wiki](https://github.com/dullage/flatnotes/wiki) for more details.
 
@@ -118,3 +119,32 @@ A special thanks to 2 fantastic open-source projects that make flatnotes possibl
 
 * [Whoosh](https://whoosh.readthedocs.io/en/latest/intro.html) - A fast, pure Python search engine library.
 * [TOAST UI Editor](https://ui.toast.com/tui-editor) - A GFM Markdown and WYSIWYG editor for the browser.
+
+## Contributing
+
+Requirements:
+
+- python3, node, npm, pipenv
+
+### Local run
+
+
+1. Install deps:
+
+    pipenv install
+    npm install
+
+3. Build UI
+
+    npm run build
+
+4. Switch to virtual environment
+
+    pipenv shell
+    mkdir notes # for local test, it's git-ignored
+
+5. Run local server
+
+    FLATNOTES_PATH=notes FLATNOTES_AUTH_TYPE=none uvicorn --app-dir server main:app --port 8080 
+    
+Dev instance will be available on http://127.0.0.1:8080
\ No newline at end of file
diff --git a/server/notes/file_system/file_system.py b/server/notes/file_system/file_system.py
index a463b41..8a9781b 100644
--- a/server/notes/file_system/file_system.py
+++ b/server/notes/file_system/file_system.py
@@ -3,6 +3,7 @@
 import re
 import shutil
 import time
+import subprocess
 from datetime import datetime
 from typing import List, Literal, Set, Tuple
 
@@ -58,6 +59,7 @@ def create(self, data: NoteCreate) -> Note:
         """Create a new note."""
         filepath = self._path_from_title(data.title)
         self._write_file(filepath, data.content)
+        self._exec_hook("create", filepath)
         return Note(
             title=data.title,
             content=data.content,
@@ -93,6 +95,8 @@ def update(self, title: str, data: NoteUpdate) -> Note:
             content = data.new_content
         else:
             content = self._read_file(filepath)
+
+        self._exec_hook("update", filepath)
         return Note(
             title=title,
             content=content,
@@ -104,6 +108,7 @@ def delete(self, title: str) -> None:
         is_valid_filename(title)
         filepath = self._path_from_title(title)
         os.remove(filepath)
+        self._exec_hook("delete", filepath)
 
     def search(
         self,
@@ -372,6 +377,22 @@ def _fieldnames_for_term(self, term: str) -> List[str]:
             fields.append("tags")
         return fields
 
+    def _exec_hook(self, hook_name: Literal["create", "update", "delete"], path: str):
+        """Execute shell script for provided hook.
+        The hook script will be from FLATNOTES_HOOK_<name>, where name is a hook_name in upper case.
+        If there is no such env, hook will be ignored. Workdir is the storage path.
+        Changed path will be substituted from %s.
+        """
+        hook_env_name = f"FLATNOTES_HOOK_{hook_name.strip().upper()}"
+        script = os.getenv(hook_env_name)
+        if not script:
+            return
+        subprocess.check_call(
+            script.replace("%s", path),
+            shell=True,
+            cwd=self.storage_path,
+        )
+
     @staticmethod
     def _get_matched_fields(matched_terms):
         """Return a set of matched fields from a set of ('field', 'term') "