Understand what needs protecting
Map important data, business processes and trust boundaries. Ask what failure would mean for the people using the system. This creates a shared basis for architectural decisions.
Make assumptions explicit
Document how users authenticate, where authorization is enforced and how credentials are managed. Examine dependencies and external integrations. Assumptions are easier to test when they are written down.
Plan for recovery
Design logs, backups and recovery procedures alongside application features. Verify that teams can restore a service and communicate clearly when something goes wrong. A written plan only becomes useful when it can be exercised.
Keep responsibility shared
Security specialists and delivery teams need a common backlog of prioritized improvements. Treat unresolved risks as visible decisions with owners, rather than an isolated report handed over at the end.