Design Doc Fall 2022 Dev Dojo @hide 

Design Doc - What? A technical spec about feature or system which includes the rationale for each decision made. 

Design Doc - Why? ● Transfer knowledge ● Improve quality by getting feedback ● Other teammates can use their experience to help point out potential errors before they happen ● Clarify your thoughts about a design by writing them down to make them more real and feasible than having them in your head ● Improve code review quality ● Get alignment with architecture and other technical detail 

Design Doc - When? Spec Discussion Design doc Development PM plans to think of new idea Design and functionallity are fixed Start development after getting approval for design doc 

Design Doc - Process Design Discussion Review Code Before writing code,and/or while prototyping By people having an insight for the domain Incorporate insight and idea Similar to “develop/review code” but It costs much less if written before actual code 

Design Doc - Lifespan ● Design Docs are a historical document ○ Understand why decisions were made in the past ○ Don't update them ○ They are not documentation ○ For changes, write a new design doc ■ Maybe link to it from the old one ● Non-historical document ○ e.g. confluence, onboarding wiki 

Design Doc - How? ● Follow the templates to start ○ An Example Template ○ Some teams have their own template ● Put it in Team Drive ○ #group-design-doc ● Get feedbacks by review ○ Guideline for reviews 

Design Doc - Teams ● Each team may have a different process ○ Design Docs may be required before implementation of some features ○ Other engineers or the tech lead may need to approve ○ Templates might be different ○ Some teams may not have a design doc flow ● Individual ○ Even if you team does not require it, you might write design docs for your own learning