python-canonicaljson >= 1.1.3 is required by recent versions of matrix-synapse. With python-canonicaljson-1.0.0, synapse fails to start with: Missing Requirement: Version of 'canonicaljson>=1.1.3' in '/usr/lib/python2.7/site-packages/canonicaljson.pyc' is too old. '1.0.0' < '1.1.3' To install run: pip install --upgrade --force "canonicaljson>=1.1.3"