Technical design is about planning the solution and putting together a skeleton of the technical solution. Putting together good design documentation will help you to avoid development rework and improve the quality of code by allowing you to think through several facets of the solution before you start coding. TDD speaks the language of applications and, often, the code and technology, to achieve the solution. It is incumbent on the solution architect and technical leads writing the TDD to have expert knowledge about the system, design patterns, limitations, and the recommended customization approach.

Consider the following guidelines when writing TDDs:

• Follow the Microsoft roadmap as to where the overall solution is headed—what new features are on the roadmap and what features will be deprecated in the future. 
• Utilize the innovation happening in the cloud. There are many Azure cloud solution platforms such as the Power Platform, Logic App, Azure Data Factory, machine learning, and many others that can be utilized with Finance and Operations to solve complex problems. 
• Utilize the standard solution frameworks as much as possible and extend if required.

• Be cognizant of the cloud-first solution approach; consider the edge and on-premises scenarios in your custom solution.
• Consider recommendations and best practices when designing a solution.
• The technical design typically starts after the sign-off of the functional design. It can also start early for a functional area where the requirements are clear.
• Engage the technical lead early on during functional designing to understand the functional requirements and flow.
• Plan brainstorming sessions among the team to discuss different solution ideas.
• Plan separate technical specs for integrations and data migration.
• Plan communications within the team to handle cross-functional designs.