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Show HN: Katharos Functional programming and CSP-style concurrency for Python
Python developers can now replace scattered None checks and nested try/except blocks with composable, type-safe values that short-circuit on failure, reducing boilerplate and making error paths explicit. The CSP concurrency model treats channel closure as a value rather than an exception, which makes concurrent error handling more predictable and composable.
Written by elseif from the cluster below · every claim links back to a sourceThe three things worth knowing
The library provides do-notation via decorators and yield, allowing imperative-style monadic composition that works with Maybe, Result, IO, ImmutableList, and custom monads.
CSP-style concurrency uses typed Channels where recv() returns Success or Failure (e.g., ChannelClosedError), and the go context manager provides structured concurrency that joins all spawned work before exiting the block.
The concurrency runtime uses a swappable BaseThreadingBackend abstraction (defaulting to standard threads), allowing retargeting to different backends, with additional models like actors planned.
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