Last week, a meeting of UralJS was held in Yekaterinburg. We again gathered a hundred developers and broke the coworking - we had to put an additional monitor in the kitchen and duplicate the projector screen to remove the load on the main hall.

By tradition, there were three speakers - a freelancer, a contourist, and an evil Martian. Here is what we discussed:

Nikolay Karev - this is evil

The this keyword introduces an implicit state into the application and generates dependencies within the class. Kolya's report on how to solve these problems with functional programming tools.

If you've never heard of lenses and currying, check out the link. Kolya not only explains what it is, but also gives real examples where they can come in handy.

Mikhail Shatikhin - Ruthless Typing

Using TypeScript as an example, Misha talks about the benefits of typing — eliminating typos, predictable input parameters, auto-completion in the code editor, and the disappearance of tests for entire classes of errors.

Misha's report is primarily an instruction for those who want to add types to a Redux application, but don’t know how. Especially for such a case, Misha made a typing plan and methodically moved along it, telling in detail about the syntax and instant goodies for the developer.

Alexey Ivanov - React and Data: Effective Ways to Store and Change State

A story about how to optimize the work of a tree of several hundred components. If your checkboxes are set for half a second, there are pauses when entering data in the text field, and animations only interfere with the normal operation of the application - this report is for you.

Alex tells how React works from the inside. This is necessary to know in order to reduce the number of insertions and recalculations - they affect the application performance. From simple manipulations in DevTools, Lesha moves to more complex ones, which at the end of the report were reduced to a concise checklist:

Leave questions and impressions in the comments, subscribe to our YouTube channel and, if you live nearby, join our community as listeners and speakers.

UralJS # 7

We are already preparing UralJS # 7.

Participate in the compilation of the program in the Github repository . Just create a new issue to add your report or suggest a topic for someone. For ideas you can vote by likes, and in the comments ask questions and share useful materials on the topic.

See you in April :)