When everything has been installed and configured, the actual development can start! At this moment it’s wise to refer to the UX Flow, Wireframes, Pieces and Pages that were created in the Map and Design phases - that should contain all information for the developer to know what needs to be developed.
Moreover being approved by the client - all extra functionality is out of the scope and need to be documented or added to the backlog as extra tasks.
As the 10 phases is not about any particular frameworks or CMS I won’t go deeper into the technical part of developing. The only thing that need to be mentioned is to: ‘Think modular’, so try to code in reusable Partials (components) - that can be used in upcoming projects so valuable time can be used to make products better, nicer and more efficient to develop.
The DRY concept also applies to development maybe even more than in design. Creating a pattern library is proved way of working and moreover a good investment for future projects and will contribute to a team that’s on the same wave length and conduct of code.