Katharos Functional programming and CSP-style concurrency for Python

In plain words

Katharos is a Python library that brings functional programming and CSP-style concurrency to the language. It is designed for developers looking to write concurrent code using communicating sequential processes patterns. The tool combines functional programming paradigms with concurrency mechanisms, enabling developers to build scalable applications with cleaner code organization and safer concurrent operations.

written from the facts on this page · September 2026

From the sources

A functional programming and concurrency library for Python. Katharos pairs algebraic abstractions ( Functor , Applicative , Monad , Semigroup , Monoid ) and concrete types like Maybe , Result , ImmutableList , and IO with message-passing concurrency built on the same functional core. The two halves share one idea: model errors, effects, and concurrent communication as composable, type-safe values . A concurrent hand-off returns a Result , so "the channel closed" is something you handle, not an exception you catch. user = find_user ( user_id ) if user is None : return None account = find_account ( user ) if account is None : return None return account . discount After: do -notation that…from github.com

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