diff --git a/cmdeploy/src/cmdeploy/__init__.py b/cmdeploy/src/cmdeploy/__init__.py
index 6815e356..c1f407d6 100644
--- a/cmdeploy/src/cmdeploy/__init__.py
+++ b/cmdeploy/src/cmdeploy/__init__.py
@@ -681,7 +681,7 @@ def deploy_chatmail(config_path: Path, disable_mail: bool) -> None:
     check_config(config)
     mail_domain = config.mail_domain
 
-    from .www import build_webpages, get_paths
+    from .www import build_webpages, find_merge_conflict, get_paths
 
     server.group(name="Create vmail group", group="vmail", system=True)
     server.user(name="Create vmail user", user="vmail", group="vmail", system=True)
@@ -823,6 +823,8 @@ def deploy_chatmail(config_path: Path, disable_mail: bool) -> None:
     # if www_folder was set to a non-existing folder, skip upload
     if not www_path.is_dir():
         logger.warning("Building web pages is disabled in chatmail.ini, skipping")
+    elif (path := find_merge_conflict(src_dir)) is not None:
+        logger.warning(f"Merge conflict found in {path}, skipping")
     else:
         # if www_folder is a hugo page, build it
         if build_dir:
diff --git a/cmdeploy/src/cmdeploy/www.py b/cmdeploy/src/cmdeploy/www.py
index c013d741..03b5af98 100644
--- a/cmdeploy/src/cmdeploy/www.py
+++ b/cmdeploy/src/cmdeploy/www.py
@@ -4,6 +4,7 @@ import time
 import traceback
 import webbrowser
 from pathlib import Path
+import re
 
 import markdown
 from chatmaild.config import read_config
@@ -12,6 +13,9 @@ from jinja2 import Template
 from .genqr import gen_qr_png_data
 
 
+_MERGE_CONFLICT_RE = re.compile(r"^<<<<<<<.+^=======.+^>>>>>>>", re.DOTALL | re.MULTILINE)
+
+
 def snapshot_dir_stats(somedir):
     d = {}
     for path in somedir.iterdir():
@@ -116,6 +120,17 @@ def _build_webpages(src_dir, build_dir, config):
     return build_dir
 
 
+def find_merge_conflict(src_dir) -> Path:
+    assert src_dir.exists(), src_dir
+    result = None
+    for path in src_dir.iterdir():
+        if path.suffix in [".css", ".html", ".md"]:
+            if _MERGE_CONFLICT_RE.search(path.read_text()):
+                result = path
+                break
+    return result
+
+
 def main():
     path = importlib.resources.files(__package__)
     reporoot = path.joinpath("../../../").resolve()