funcy
A fancy and practical functional tools
Decision gist · record as of 2026-08-14
Yes. Funcy is stable, actively maintained, has no dependencies, and offers genuine practical value for functional programming patterns in Python. The BSD license is permissive, and the library's age (since 2012) and popularity (top 5000 PyPI packages) demonstrate real-world adoption. Install it if you write functional-style Python or want to reduce boilerplate in collection transformations and function composition.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Low friction: pure Python wheel with no runtime dependencies.
- Actively maintained with a recent commit on 2026-04-19 and stable production status since its first release in 2012-11-18.
License · maintenance · safety
BSD (permissive) — BSD permissive license allows unrestricted use, modification, and distribution in both open-source and commercial projects with minimal obligations.
last release 2023-03-28 (1235 days) · last repo commit 2026-04-19 · 3,509 stars
0 known vulnerabilities (OSV.dev, 2026-08-14) · 7,191,194 downloads/mo, #1,771 on PyPI
Alternatives
Verify before relying
pip install funcy
from funcy import walk, merge, select, take, iterate
# Transform a dict's values
result = walk(str.upper, {'a': 'hello', 'b': 'world'})
# Merge multiple collections
merged = merge({'x': 1}, {'y': 2})
# Select items matching a predicate
evens = select(lambda x: x % 2 == 0, [1, 2, 3, 4])- Whether the package is actively maintained beyond the last commit date (2026-04-19) or if development has stalled
- Performance characteristics when working with very large collections or deeply nested structures
What it is and what it does
Funcy is a library of functional programming tools inspired by Clojure and underscore.js, providing utilities for working with collections, composing functions, and abstracting control flow. It includes functions for merging and transforming collections (dicts, sets, lists, tuples, iterators, strings), selecting and filtering elements, manipulating sequences, and creating decorators. The library also offers higher-order function utilities like partial application, currying, and composition, plus control-flow helpers like retry, suppress, and caching.
The package targets developers who want functional programming patterns without heavyweight frameworks. It works across Python 3.4+ and PyPy3, with no external dependencies, making it lightweight to integrate into existing projects. The API is designed around practicality—functions preserve collection types where sensible, and common operations have both eager (list-returning) and lazy (iterator-returning) variants.
Use it for
- Transform nested data structures (dicts, lists) while preserving types using walk, walk_keys, walk_values
- Merge multiple collections of the same type in a single operation
- Filter and select subsets of collections using predicates without explicit loops
- Compose functions and create partial applications for cleaner, more reusable code
- Build decorators for retry logic, error suppression, rate limiting, and caching without boilerplate
- Debug data flow by tapping values and logging function calls and durations
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
Yes.
Funcy is stable, actively maintained, has no dependencies, and offers genuine practical value for functional programming patterns in Python. The BSD license is permissive, and the library's age (since 2012) and popularity (top 5000 PyPI packages) demonstrate real-world adoption. Install it if you write functional-style Python or want to reduce boilerplate in collection transformations and function composition.
Install
funcy on PyPI
Before you install
Low friction: pure Python wheel with no runtime dependencies. Actively maintained with a recent commit on 2026-04-19 and stable production status since its first release in 2012-11-18.
License in practice
BSD permissive license allows unrestricted use, modification, and distribution in both open-source and commercial projects with minimal obligations.
Quickstart
pip install funcy
from funcy import walk, merge, select, take, iterate
# Transform a dict's values
result = walk(str.upper, {'a': 'hello', 'b': 'world'})
# Merge multiple collections
merged = merge({'x': 1}, {'y': 2})
# Select items matching a predicate
evens = select(lambda x: x % 2 == 0, [1, 2, 3, 4])Verify before relying
- Whether the package is actively maintained beyond the last commit date (2026-04-19) or if development has stalled
- Performance characteristics when working with very large collections or deeply nested structures
Package facts
| License | BSD permissive |
| Python support | Not specified |
| Install friction | Low. Pure-Python wheel |
| Runtime dependencies | None |
| Maintenance | Actively maintained 1,235 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 7,191,194 / month, #1,771 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Development Status :: 5 - Production/StableIntended Audience :: DevelopersLicense :: OSI Approved :: BSD LicenseOperating System :: OS IndependentProgramming Language :: PythonProgramming Language :: Python :: 3Programming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.4Programming Language :: Python :: 3.5Programming Language :: Python :: 3.6Programming Language :: Python :: 3.7Programming Language :: Python :: 3.8Programming Language :: Python :: 3.9Programming Language :: Python :: Implementation :: CPythonProgramming Language :: Python :: Implementation :: PyPyTopic :: Software Development :: Libraries :: Python Modules |
Evidence: funcy-2.0-py2.py3-none-any.whl
Tags
Let your AI agent find packages like this
Example. Real query, live index.
You found this page by searching. An agent finds it by wishing: SkillFed indexes 14,416 PyPI packages by what they can do, searchable in plain language.
wish › “collection transformation functions”
- funcyFuncy provides a collection of functional programming…
- pydashPydash provides a collection of functional utility functions for…
- dictknifedictknife provides utility functions for manipulating, querying, and…
Give your agent the search over MCP, or paste the wish link into any chat.
More Python Modules packages
Converts domain names between Unicode and ASCII-compatible encoding (Punycode) according to IDNA 2008 and Unicode Technical Standard 46, with security validation and broader script coverage than the standard library.
Install it if you work with internationalized domain names, need to validate domains, or use HTTP clients that depend on it transitively.
Setuptools is a Python build backend and package management tool that handles building, distributing, and installing Python packages, including support for C/C++ extension modules.
PyYAML parses and emits YAML 1.1 data format, enabling serialization and deserialization of configuration files and Python objects to and from human-readable YAML text.
Pydantic validates Python data structures against type hints, coercing and checking input at runtime to ensure it matches a declared schema.
Provides reusable metadata objects for use with PEP-593 `typing.Annotated` to express common constraints like bounds, collection sizes, and predicates on types.
Install it if you use or build libraries that need to express type constraints in a standardized, inspectable way—or if you want to annotate your own types with…
Provides runtime tools to inspect and introspect Python type annotations, enabling programmatic examination of type hints at execution time.
See also jaraco.functools · pydash · toolz · pyfunctional · cons · Expression · lmz · retry-decorator · cytoolz · decorator