Empathy plays the most important role in writing solid code. Besides, you need to choose a sustainable architecture to decrease human resource costs in total as the project scales. Then, adopt patterns and best practices; avoid anti-patterns. Finally, refactor if necessary.

There are many metrics to measure the quality of a product: the number of active users, profit, transaction volume, retention rate, and more. To ensure better product development, it is essential to focus on the following metrics: improve retention rate, as high retention means high valuation; assess weekly growth rate, maintaining its level will lead to exponential growth; prioritize iteration speed. When it comes to metrics, we must approach them correctly.

Four main reasons why smart people have bad ideas: bad ideas are products of intuition; bad ideas prioritize being impressive over making money; bad ideas yield to fear of competition; bad ideas are too superficial. Therefore, smart people must clearly understand user needs and conduct user research to unleash endless potential and truly do smart things.

If you want to manage money in a better way, what you need is more understanding of your financial status. Beancount.io is such a tool that assists you by recording your financial transactions in text files and visualizing them into financial statements.

The quadrant diagram of market and technology determines the company's market position. With the inflation of technology, excellent technologies tend to become mediocre, and mediocre companies adopt excellent technologies; companies with a market will have a larger market, while those without a market will have a smaller one.

Requirements

Design a money-transfer backend system that can receive, send, and payout. It should cover issues like scaling, internationalization, Deduplication, single-point failure, strong consistency.

Design a webhook that notifies the merchant when the payment succeeds. We need to aggregate the metrics (e.g., success vs. failure) and display it on the dashboard.

Initiating a conversation with strangers is the biggest social fear. Actually, people often appreciate it when you make an effort to speak with them. Here we provide some ideas on how to start a small talk, what we should talk about and how to end it in a courteous way.

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Amazon's ambition to gain a share of all economic activities led it to enter the grocery service market. However, based on an analysis of Amazon's existing strategy and the cost disadvantages in fresh produce, it does not currently have a first and best supplier in grocery. Acquiring Whole Foods allowed Amazon to not only buy a retailer but also gain a customer for its existing business.

Requirements