diff --git a/src/pycalver/__main__.py b/src/pycalver/__main__.py
index af6d607..2f03c13 100644
--- a/src/pycalver/__main__.py
+++ b/src/pycalver/__main__.py
@@ -240,4 +240,11 @@ def bump(
     if dry or not cfg.commit:
         return
 
-    # TODO (mb 2018-09-04): add files and commit
+    for filepath in filepaths:
+        _vcs.add(filepath)
+
+    _vcs.commit(f"bump version to {new_version}")
+
+    if cfg.tag:
+        _vcs.tag(new_version)
+        _vcs.push()
diff --git a/src/pycalver/config.py b/src/pycalver/config.py
index 22efd18..d08a886 100644
--- a/src/pycalver/config.py
+++ b/src/pycalver/config.py
@@ -119,6 +119,11 @@ def _parse_buffer(cfg_buffer: io.StringIO, config_filename: str = "<pycalver.cfg
     if file_patterns is None:
         return None
 
+    if tag and not commit:
+        log.error(f"Invalid configuration in {config_filename}")
+        log.error("     pycalver.commit = True required if pycalver.tag = True")
+        return None
+
     cfg = Config(current_version, tag, commit, file_patterns)
 
     log.debug(cfg._debug_str())
diff --git a/src/pycalver/vcs.py b/src/pycalver/vcs.py
index df12ca9..fa31a3c 100644
--- a/src/pycalver/vcs.py
+++ b/src/pycalver/vcs.py
@@ -69,6 +69,9 @@ class VCS:
                 return False
             raise
 
+    def fetch(self) -> None:
+        self('fetch')
+
     def status(self) -> typ.List[str]:
         status_output = self('status')
         return [
@@ -77,8 +80,12 @@ class VCS:
             if not line.strip().startswith(b"??")
         ]
 
-    def fetch(self) -> None:
-        self('fetch')
+    def ls_tags(self) -> typ.List[str]:
+        ls_tag_lines = self('ls_tags').splitlines()
+        log.debug(f"ls_tags output {ls_tag_lines}")
+        return [
+            line.decode("utf-8").strip() for line in ls_tag_lines if line.strip().startswith(b"v")
+        ]
 
     def add(self, path) -> None:
         log.info(f"{self.name} add {path}")
@@ -104,12 +111,8 @@ class VCS:
     def tag(self, name) -> None:
         self('tag', name=name)
 
-    def ls_tags(self) -> typ.List[str]:
-        ls_tag_lines = self('ls_tags').splitlines()
-        log.debug(f"ls_tags output {ls_tag_lines}")
-        return [
-            line.decode("utf-8").strip() for line in ls_tag_lines if line.strip().startswith(b"v")
-        ]
+    def push(self) -> None:
+        self('push')
 
     def __repr__(self) -> str:
         return f"VCS(name='{self.name}')"