Architecture can directly impact costs per feature. Let's compare Tight-coupling MVC, Cocoa MVC, MVP, MVVM, and VIPER in three dimensions: balanced distribution of responsibility among feature actors, testability and ease of use and maintainability.

The key-value cache is used to reduce the latency of data access. What are read-through, write-through, write-behind, write-back, write-behind, and cache-aside patterns?

Traditional NFS based design has metadata bottleneck: large metadata size limits the metadata hit ratio. Facebook photo storage eliminates the metadata by aggregating hundreds of thousands of images in a single haystack store file.

Disclaimer: All things below are collected from public sources or purely original. No Uber-confidential stuff here.

Names are a very important weapon. Researchers at Syracuse University found that when people use derogatory terms to refer to a certain social group, the suicide rate among that group tends to be higher. Names can also unite people; experimental results show that the name of a game influences people's ability to cooperate. When people cheer for themselves during a competition, they often achieve their best performance.

A blockchain is an incorruptible distributed ledger that is hosted by multiple parties, secured by crypto algorithms and immutable and verifiable in data storage. The blockchain technology is applied in a wide range of industries.

The cycle system enables people to follow through. It suggests every day should start with your to-do list, hours needed and plans. The secrets also lie in writing down goals and scheduling things with the calendar, instead of your brain.

Different auth systems solve the problem with different needs. For a new start-up who does not want to build their own auth systems, the most suitable solution is auth0. Meanwhile, the best solution for a company that needs integrations of enterprise services is OneLogin.

People cannot dominate an industry solely with superior technical skills, as the replicability and update rate of technology are extremely high. Maintaining a curious mind and deliberately exploring the world is another necessary condition for enhancing one's competitiveness. Allen Gannett interviewed numerous creative individuals and concluded that we must spend 20% of our waking time each day absorbing knowledge in our respective fields.

The persuasive techniques used by the Greeks let you appear clever when speaking. Other schemes include figures of speech, twisting clichés, Yoda speaking, dialysis, antithesis, saying both yes and no and inventing new words.

Sustainable user engagement should be built through three levels: user growth, focusing on the growth of users completing core actions; user retention, where the longer the product is used, the greater its value, and the greater the loss when users leave; self-sustaining, where users create a positive feedback loop through their participation in the product.

To improve the chances of success in persuading decision-makers, the way of message delivering should be considered carefully. There are five decision-making categories and they should be treated with different strategies.