Access Restriction: Restrict the access to contract functionality according to suitable criteria. Checks Effects Interactions: Reduce the attack surface for malicious contracts trying to hijack control flow after an external call. Pullover Push: Shift the risk associated with transferring XLG to the user. Circuit Breaker: Add an option to disable critical contract functionality in case of an emergency. Speed Bumps: introduces a delay in the action execution allowing time to act if action is considered malicious. Arithmetic: Integer overflows and underflows are dangerous in smart contracts. If these occur, many benign-seeming code paths become vectors for theft or denial of service.