When comparing CakePHP vs Koa, the Slant community recommends Koa for most people. In the question“What are the best backend web frameworks?” Koa is ranked 33rd while CakePHP is ranked 50th. The most important reason people chose Koa is:
Using generators (a bleeding edge feature, even for Node.js) would clean up your code from the mess caused by all those callbacks; making your code more manageable.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Built-in ORM that's easy to use
Cake has a built-in ORM which is pretty easy to use and learn. Building queries can also be done very easily and fetching entire columns can be done in one or two lines of code.
Pro Fast development
Developing in CakePHP is very fast and flexible.
CakePHP is about fast and reliable development, it achieves this by following the convention over configuration principle as it's heavily inspired by Rails (which follows the same programming paradigm).
Convention over configuration is all about making it easier for the developer to start immediately writing code without worrying on what's going on "under the hood".
Pro Large library of helper classes
CakePHP has a large library of helper classes with features such as:
- Authorization
- AJAX
- Forms
- E-mails
- Internationalization
etc...
Pro Exhaustive list of resources to learn CakePHP
Cake's great community has thrown together an exhaustive and amazing list of resources to get started with CakePHP. It's open source and can be found on GitHub.
Pro Open Source
CakePHP open source and is licensed under the MIT license.
Pro Generator support from ground up
Using generators (a bleeding edge feature, even for Node.js) would clean up your code from the mess caused by all those callbacks; making your code more manageable.
Pro Extremely lightweight
Koa is very lightweight with just 550 lines of code.
Pro async/await keywords are supported and has transcended beyond generator functions
Generators functions are of course a huge plus, but at the time Koa team has transcended generations functions and shifted towards async/await style programming. It has made the Koa best framework available in the market.
Pro Development team has a proven track record
Koa is developed by the team behind a widely used node.js framework (express.js).

Pro Built for ES6
Cons
Con Slow
Because of legacy code, old concepts and prioritizing development speed over everything else, CakePHP is bloated and slow.
Con Community is relatively small
Con Not compatible with express style middleware
Koa uses generators which are not compatible with any other type of Node.js framework middleware.
Con Has no routes separated by HTTP method or URL pattern
Con Wrong Middle ware, security issue
