warp-cache 0.2.0

Thread-safe Python caching decorator backed by a Rust extension

warp_cache

A thread-safe Python caching decorator backed by a Rust extension. Through a series of optimizations — eliminating serialization, moving the call wrapper into Rust, applying link-time optimization, and using direct C API calls — we achieve 0.55-0.66x of lru_cache's single-threaded throughput while providing native thread safety that delivers 1.3-1.4x higher throughput under concurrent load — and 18-24x faster than pure-Python cachetools.

Features

• Drop-in replacement for functools.lru_cache — same decorator pattern and hashable-argument requirement, with added thread safety, TTL, eviction strategies, and async support
• Thread-safe out of the box (parking_lot::RwLock in Rust)
• Async support: works with async def functions — zero overhead on sync path
• Shared memory backend: cross-process caching via mmap
• Multiple eviction strategies: LRU, MRU, FIFO, LFU
• TTL support: optional time-to-live expiration
• Single FFI crossing: entire cache lookup happens in Rust, no Python wrapper overhead
• 12-18M ops/s single-threaded, 16M ops/s under concurrent load, 18-24x faster than cachetools

Installation

Prebuilt wheels are available for Linux (x86_64, aarch64), macOS (x86_64, arm64), and Windows (x86_64):

pip install warp_cache

If no wheel is available for your platform, pip will fall back to the source distribution (requires a Rust toolchain).

Quick example

from warp_cache import cache

@cache()
def expensive(x, y):
    return x + y

expensive(1, 2)  # computes and caches
expensive(1, 2)  # returns cached result

If you're already using functools.lru_cache, switching is a one-line change:

-from functools import lru_cache
+from warp_cache import cache

-@lru_cache(maxsize=128)
+@cache(max_size=128)
 def expensive(x, y):
     return x + y

Like lru_cache, all arguments must be hashable. See the usage guide for details.

Performance at a glance

Metric	warp_cache	cachetools	lru_cache
Single-threaded	12-18M ops/s	0.6-1.2M ops/s	21-40M ops/s
Multi-threaded (8T)	16M ops/s	770K ops/s (with Lock)	12M ops/s (with Lock)
Thread-safe	Yes (RwLock)	No (manual Lock)	No
Async support	Yes	No	No
Cross-process (shared)	~7.8M ops/s (mmap)	No	No
TTL support	Yes	Yes	No
Eviction strategies	LRU, MRU, FIFO, LFU	LRU, LFU, FIFO, RR	LRU only
Implementation	Rust (PyO3)	Pure Python	C (CPython)

Under concurrent load, warp_cache delivers 1.3-1.4x higher throughput than lru_cache + Lock and 18-24x higher than cachetools. See full benchmarks for details.

Documentation

• Usage guide — eviction strategies, async, TTL, shared memory, decorator parameters
• Performance — benchmarks, architecture deep-dive, optimization journey
• Alternatives — comparison with cachebox, moka-py, cachetools, lru_cache
• Examples — runnable scripts for every feature (uv run examples/<name>.py)
• llms.txt / llms-full.txt — project info for LLMs and AI agents (spec)

Contributing

Contributions are welcome! See CONTRIBUTING.md for setup instructions, coding standards, and PR guidelines.

For security issues, please see SECURITY.md.

License

MIT