Go Packages

This covers the structural decisions you make when organizing Go code: when to split packages, how to group imports, whether that init() is actually necessary, and where os.Exit belongs (spoiler: only in main). It's opinionated in the right ways, like telling you to avoid util packages and generic names that obscure meaning. The package sizing guidance is genuinely helpful, with a table that asks whether you can describe the package purpose in one sentence. Also includes the run() pattern for CLI tools and flags in snake_case, which catches people off guard if they're coming from other languages. Draws from Google and Uber style guides, so it's not just someone's blog post preferences.