diff --git a/app/__init__.py b/app/__init__.py
index 4219fa9..8a8a505 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -68,6 +68,56 @@
 }
 
 
+def _bootstrap_alembic_version(app):
+    """Stamp alembic_version for databases that predate Flask-Migrate.
+
+    Early versions of May created tables via db.create_all() without
+    Flask-Migrate. When those users upgrade, `alembic_version` is either
+    missing or empty, so `flask db upgrade` tries to replay migrations
+    from scratch and fails on `duplicate column` errors. Columns that
+    later migrations add therefore never land, and the app crashes
+    at startup (see issues #132, #136).
+
+    If we detect an established schema with no alembic revision recorded,
+    stamp the most recent migration whose columns already exist so that
+    subsequent `flask db upgrade` runs only apply genuinely new changes.
+    """
+    from sqlalchemy import text, inspect
+    from flask_migrate import stamp
+
+    inspector = inspect(db.engine)
+    table_names = inspector.get_table_names()
+    if 'users' not in table_names or 'vehicles' not in table_names:
+        return
+
+    with db.engine.begin() as conn:
+        if 'alembic_version' in table_names:
+            current = conn.execute(
+                text('SELECT version_num FROM alembic_version')
+            ).scalar()
+            if current:
+                return
+
+    user_cols = {c['name'] for c in inspector.get_columns('users')}
+    vehicle_cols = {c['name'] for c in inspector.get_columns('vehicles')}
+
+    if 'default_vehicle_id' in user_cols:
+        target = 'a1b2c3d4e5f6'
+    elif 'odometer_unit' in vehicle_cols:
+        target = '613be8af4376'
+    else:
+        target = None
+
+    if target is None:
+        return
+
+    try:
+        stamp(revision=target)
+        app.logger.info(f'Stamped alembic_version to {target} for pre-migration database')
+    except Exception as e:
+        app.logger.warning(f'Could not stamp alembic_version: {e}')
+
+
 def _run_schema_migrations(app):
     """Add missing columns to existing tables.
 
@@ -91,6 +141,7 @@ def _run_schema_migrations(app):
             ('date_format', "VARCHAR(20) DEFAULT 'DD/MM/YYYY'"),
             ('password_reset_token', 'VARCHAR(100)'),
             ('password_reset_expires', 'DATETIME'),
+            ('default_vehicle_id', 'INTEGER REFERENCES vehicles(id)'),
         ],
         'charging_sessions': [
             ('tessie_charge_id', 'VARCHAR(50)'),
@@ -248,6 +299,9 @@ def add_security_headers(response):
 
     with app.app_context():
         db.create_all()
+        # Stamp alembic_version for pre-Flask-Migrate databases so future
+        # `flask db upgrade` runs apply only pending migrations.
+        _bootstrap_alembic_version(app)
         # Run schema migrations for new columns on existing tables
         _run_schema_migrations(app)
         # Create default admin user if no users exist
diff --git a/config.py b/config.py
index 77ddd6f..73957e3 100644
--- a/config.py
+++ b/config.py
@@ -4,7 +4,7 @@
 basedir = Path(__file__).parent.absolute()
 
 
-APP_VERSION = '0.18.0'
+APP_VERSION = '0.18.1'
 RELEASE_CHANNEL = os.environ.get('RELEASE_CHANNEL', 'stable')
 GIT_SHA = os.environ.get('GIT_SHA', '')[:7]  # Short SHA
 GITHUB_REPO = 'dannymcc/may'
diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 5a38c7a..f5ac56f 100644
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -11,8 +11,11 @@ fi
 mkdir -p /app/data/uploads
 chown -R may:may /app/data
 
-# Run database migrations as the may user
-gosu may flask db upgrade 2>/dev/null || true
+# Run database migrations as the may user. Failures are logged rather than
+# silently swallowed so upgrade problems are visible in container logs.
+if ! gosu may flask db upgrade; then
+    echo "[entrypoint] flask db upgrade failed — the app will attempt schema recovery on startup." >&2
+fi
 
 # Drop to 'may' user and run the application
 exec gosu may "$@"
diff --git a/migrations/versions/613be8af4376_allow_nullable_amount_on_recurring_.py b/migrations/versions/613be8af4376_allow_nullable_amount_on_recurring_.py
index 7bf643c..fcb284e 100644
--- a/migrations/versions/613be8af4376_allow_nullable_amount_on_recurring_.py
+++ b/migrations/versions/613be8af4376_allow_nullable_amount_on_recurring_.py
@@ -7,6 +7,7 @@
 """
 from alembic import op
 import sqlalchemy as sa
+from sqlalchemy import inspect
 
 
 # revision identifiers, used by Alembic.
@@ -17,6 +18,17 @@
 
 
 def upgrade():
+    bind = op.get_bind()
+    inspector = inspect(bind)
+    if 'recurring_expenses' not in inspector.get_table_names():
+        return
+    amount_col = next(
+        (c for c in inspector.get_columns('recurring_expenses') if c['name'] == 'amount'),
+        None,
+    )
+    if amount_col is not None and amount_col.get('nullable') is True:
+        return
+
     with op.batch_alter_table('recurring_expenses', schema=None) as batch_op:
         batch_op.alter_column('amount',
                existing_type=sa.FLOAT(),
diff --git a/migrations/versions/998cdb1497c6_add_odometer_unit_to_vehicles.py b/migrations/versions/998cdb1497c6_add_odometer_unit_to_vehicles.py
index bbccddc..cd4d3b8 100644
--- a/migrations/versions/998cdb1497c6_add_odometer_unit_to_vehicles.py
+++ b/migrations/versions/998cdb1497c6_add_odometer_unit_to_vehicles.py
@@ -7,6 +7,7 @@
 """
 from alembic import op
 import sqlalchemy as sa
+from sqlalchemy import inspect
 
 
 # revision identifiers, used by Alembic.
@@ -17,6 +18,14 @@
 
 
 def upgrade():
+    bind = op.get_bind()
+    inspector = inspect(bind)
+    if 'vehicles' not in inspector.get_table_names():
+        return
+    existing_cols = [col['name'] for col in inspector.get_columns('vehicles')]
+    if 'odometer_unit' in existing_cols:
+        return
+
     with op.batch_alter_table('vehicles', schema=None) as batch_op:
         batch_op.add_column(sa.Column('odometer_unit', sa.String(length=10), nullable=True))
 
diff --git a/migrations/versions/a1b2c3d4e5f6_add_default_vehicle_nullable_trip_end_odometer.py b/migrations/versions/a1b2c3d4e5f6_add_default_vehicle_nullable_trip_end_odometer.py
index 1e5f30a..bae8e93 100644
--- a/migrations/versions/a1b2c3d4e5f6_add_default_vehicle_nullable_trip_end_odometer.py
+++ b/migrations/versions/a1b2c3d4e5f6_add_default_vehicle_nullable_trip_end_odometer.py
@@ -7,6 +7,7 @@
 """
 from alembic import op
 import sqlalchemy as sa
+from sqlalchemy import inspect
 
 
 # revision identifiers, used by Alembic.
@@ -17,12 +18,24 @@
 
 
 def upgrade():
-    with op.batch_alter_table('users', schema=None) as batch_op:
-        batch_op.add_column(sa.Column('default_vehicle_id', sa.Integer(), nullable=True))
-        batch_op.create_foreign_key('fk_users_default_vehicle', 'vehicles', ['default_vehicle_id'], ['id'])
-
-    with op.batch_alter_table('trips', schema=None) as batch_op:
-        batch_op.alter_column('end_odometer', existing_type=sa.Float(), nullable=True)
+    bind = op.get_bind()
+    inspector = inspect(bind)
+
+    if 'users' in inspector.get_table_names():
+        user_cols = [col['name'] for col in inspector.get_columns('users')]
+        if 'default_vehicle_id' not in user_cols:
+            with op.batch_alter_table('users', schema=None) as batch_op:
+                batch_op.add_column(sa.Column('default_vehicle_id', sa.Integer(), nullable=True))
+                batch_op.create_foreign_key('fk_users_default_vehicle', 'vehicles', ['default_vehicle_id'], ['id'])
+
+    if 'trips' in inspector.get_table_names():
+        end_odo = next(
+            (c for c in inspector.get_columns('trips') if c['name'] == 'end_odometer'),
+            None,
+        )
+        if end_odo is not None and end_odo.get('nullable') is not True:
+            with op.batch_alter_table('trips', schema=None) as batch_op:
+                batch_op.alter_column('end_odometer', existing_type=sa.Float(), nullable=True)
 
 
 def downgrade():