Comment by iagooar

Things I dislike the most about Ruby:

- Raw performance

- Runtime metaprogramming from hell

- Monkey patching

- No real concurrency support, tons of non-threadsafe code and gems

- Too Rails-centric

- Little presence outside web development

- Little to no real innovation in the last years

- Mutability

- No optional / progressive types or type annotations

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Things I love about Ruby:

- Clean syntax

- Although it's object oriented, it allows using a functional style

- Functional collection operations

- Productivity

- Flexibility

- Maturity

- Availability of high-quality libraries

- Availability of hosting solutions

- Friendly community

- Nice stack traces