What should a middle PHP developer know?

Question

PHP

I would like to hear from middles \ seniors \ hr what kind of knowledge a developer should have when applying for a middle position.
The answer can be divided into categories:
1) Must have - something that you should know perfectly and be sure of (here I would like as much detail as possible)
2) Work-related knowledge (server administration / frontend / mobile technologies)
3) Experience with what and how
4) Personal qualities

Answer 1

I received a very interesting vacancy the other day, in my opinion it to some extent describes what the middle should know.
- write good code in PHP from 2 years;
- you know what PHP interfaces are for
- you have MySQL design experience, understanding of the optimization mechanism for relational databases of this type;
- you use the concepts of OOP, and do not write noodle code;
- you know the basic design patterns - you know
how to understand someone else's code;
- you know about closures in JavaScript and how to write working code beautifully;
- applied AJAX and periodically use it;
- know how to write unit tests and when it is appropriate to write them;
- know about dependency injection and why it is needed for reuse, scaling and testability;
- you understand how ActiveRecord with links differs from the traditional, Fowlerian, ActiveRecord
IMHO what you need

1. know most of the differences / innovations of the last 2-3 major versions of PHP (and be able to use them correctly)
   
2. know one of the frameworks (ZF2, Symfony2, Laravel4/5) at the level of a complete understanding of the inner workings of the framework (what patterns this or that part of the system is built on, why exactly on them, how it all interacts, etc.)
   
3. know how relational DBMSs work, i.e. understanding JOINs, not only what to sculpt where, but also how it happens inside, well, with other functions as well
   
4. well, in the end, to deal with SPL , so that there would be no situations like at PHP UK Conf.
   
5. JS - to understand how everything inside is spinning, spinning. It is desirable to know some other framework (Angular, backbone, etc)
   
6. HTML, CSS - to taste (I don’t think that a php programmer should be a cool layout designer, but one does not interfere with the other, and if you like it, then this will only be a plus)
   
7. Know English, no matter what the shame at the rally
   
8. to be an adequate, sane person
   

Answer 2

All answers to questions like "What should I know ..." are on headhunter sites.

Answer 3

Middle must know everything Junior knows + at least 1-2 years of work experience.

Answer 4

PHP
Xdebug
SQL/NoSQl/Memcached
HTML
CSS
JS
Unix/Linux
Nginx/Apache
And a bunch of other books to read, such as algorithms, ideal code (I don't know if a web developer needs this) and more framework docks.
Although, maybe I lied about a lot, but if a thousand is 150 re., Then why not?

Answer 5

... I work on the principle "if necessary, I'll figure it out" ... to have an idea - yes, to thoroughly investigate each item - why?

Answer 6

If you are interested, there are statistics from the hh.ru website that are currently required for vacancies from PHP developers: link .