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Aleksei Aleinikov
Aleksei Aleinikov

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πŸŒ€ Go interfaces: simple on the surface, tricky underneath.

In 2025, too many Go projects still misuse interfaces β€” leading to nil surprises, unsafe type switches, and brittle abstractions.

⚑ Key points every Go dev should master:

  • Interfaces store type + data, so a nil pointer β‰  nil interface.
  • Empty interface {} is a last resort, not a default.
  • Keep interfaces small and local β€” easier to mock, easier to swap.
  • Type switches unlock real power (when used with care).
  • Polymorphism? Yes. Overengineering? No.

πŸ’‘ Learn where to declare them, when to assert, and how Go’s dynamic dispatch actually works behind the scenes (no "Dog/Cat" clichΓ©s).

https://levelup.gitconnected.com/go-interfaces-made-practical-in-2025-from-basics-to-real-world-use-04307f0fe02a

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