10 Things to consider during a System Takeover

Taking over an existing system is rarely an ideal situation, given you’re losing the detailed knowledge of the developers who wrote and understood every line of code, but we fully understand that sometimes it’s the best or only choice to move forward.

As we’ve undertaken many system handover and takeover projects over the years, we’ve seen the various issues that can arise from taking on existing codebases. Here are ten key areas to consider when planning a system takeover project:

1. Documentation availability: The more documentation available, the better. It provides much-needed background and context without needing to search through code for every detail. Where documentation is sparse, extra time must be allocated to code discovery.
2. Security vulnerabilities: If the system is accessible via the public internet or contains sensitive data, a security vulnerability assessment is essential. It is important to understand current risks and plan mitigation steps.
3. Software architecture: The architecture of the software needs to be mapped and reviewed to ensure it can support ongoing business requirements, planned enhancements, and scalability as the business grows.
4. Database design: A clean database design is critical for data integrity, system performance, efficient reporting, and flexibility for future development. Getting to grips with the database structure early helps identify required improvements.
5. Coding style: Coding standards vary between developers. Elegantly written code that is well-commented and structured makes ongoing maintenance efficient, whereas unstructured code requires methodical debugging to understand business logic.
6. Source code structuring: If files and code directories are poorly structured, developers will spend excessive time maintaining them. Cleaning up code structure early prevents the need for major rewrites during minor updates.
7. Languages and Frameworks: Direct experience with the specific programming languages, frameworks, and versions used in the codebase is essential for efficient onboarding.
8. Dependent libraries, licensing, and support: Research any non-standard third-party libraries or dependencies to ensure licenses are compliant and support is available. If dependencies are deprecated, plan for replacement costs and code adjustments.
9. Unit tests availability: Automated unit tests indicate the original system was built with testing in mind and allow new developers to verify that updates do not break existing functionality.
10. System environment migration: If hosting is being migrated alongside the handover, formulate a clear plan to transfer environment configurations, databases, and assets cleanly without downtime.