Core Viewpoint - The article emphasizes the importance of having a side business for programmers, highlighting the need to think like a businessman rather than just focusing on coding skills [5][6][9]. Group 1: Necessity of Side Businesses - The article discusses the vulnerabilities of relying solely on a primary job and the risks associated with a single career path, advocating for side businesses as a means to enhance career possibilities and financial security [9][10]. - Side businesses are viewed as platforms for gaining greater freedom, testing new technologies, and improving business sensitivity [10]. Group 2: Resources and Pathways for Side Businesses - The article identifies three core resources essential for side businesses: time, assets, and knowledge/network [14][16]. - It defines assets as anything that can generate passive income, including stocks, bonds, real estate, and intellectual property [15]. Group 3: Lean Side Business Methodology - The article proposes a methodology for personal side businesses based on lean startup principles, including the business model canvas, minimum viable product, and product-market fit [17]. - It provides practical examples of independent development processes, illustrating the full execution chain from user profiling to feedback and growth [18]. Group 4: Psychological and Financial Benefits - The article suggests that having a side business can provide programmers with a sense of security when facing career uncertainties, particularly around the age of 35 [21]. - It emphasizes the importance of generating income that allows for greater time freedom, not just financial gain [22][23].