Building an equivalent to Nylas, a platform that integrates with email, calendar, and contact providers, is a resource-intensive endeavor, requiring approximately $2,035,044 and 30,834 developer hours. This process typically takes over 1.5 years for a team of seven senior engineers to complete various tasks, including project scoping, testing, proof of concept creation, security certifications, and ongoing maintenance. By comparison, Nylas can achieve full integration in just 18 days, offering pre-built security features and compliance with standards like SOC 2, GDPR, and HIPAA. The document details the significant time and cost involved in building individual components for integration, such as authentication, email sync, calendar sync, and contact sync across platforms like Gmail, Microsoft Exchange, and Microsoft Graph, emphasizing the complexity and continuous maintenance required for such integrations.