Best of / Rust crates / concurrency and parallelism
Best of · ranked by real use · data Oct 24, 2026
Best Rust crates for concurrency and parallelism
Short answerBy real use, the top Rust crates for concurrency and parallelism are parking_lot (3M a day), rayon (1.6M a day), crossbeam-channel (1.6M a day). parking_lot is our default pick: 2,961,161 real downloads a day and 8,755 dependents. Gaining fastest against the field: papaya (+31%). 6 of these 10 shipped in the last 90 days.
Our picks
- Default pick: parking_lot. The most used that still ships releases, so the most answered questions and the likeliest to already be in your tree.
- Rising: papaya. +31% on quiet days against the field over 90 days.
- Most recently released: arc-swap (6 days ago).
The ranking
| # | Crate | Real downloads a day | Dependents | Trend vs field | Last release | What it is (its own description) |
|---|---|---|---|---|---|---|
| 1 | parking_lot Widely used | 2,961,161 | 8,755 | -8% | 3d | More compact and efficient implementations of the standard synchronization primitives |
| 2 | rayon Foundational | 1,615,491 | 11,972 | +2% | 6mo | Simple work-stealing parallelism for Rust |
| 3 | crossbeam-channel Widely used | 1,564,625 | 2,767 | -4% | 49d | Multi-producer multi-consumer channels for message passing |
| 4 | arc-swap Widely used | 1,156,989 | 2,131 | -4% | 6d | Atomically swappable Arc |
| 5 | dashmap Widely used | 1,112,131 | 4,694 | -9% | 5mo | Blazing fast concurrent HashMap for Rust |
| 6 | async-channel Widely used | 881,815 | 1,037 | -5% | 16mo | Async multi-producer multi-consumer channel |
| 7 | flume Established | 768,860 | 970 | +3% | 11mo | A blazingly fast multi-producer channel |
| 8 | moka Established | 527,705 | 743 | -8% | 2mo | A fast and concurrent cache library inspired by Java Caffeine |
| 9 | crossbeam Widely used | 374,913 | 1,418 | -21% | 49d | Tools for concurrent programming |
| 10 | papaya Established | 67,338 | 103 | +31% | 2mo | A fast and ergonomic concurrent hash-table for read-heavy workloads |
Rules
Candidates: crates whose own README says they do this job, picked by hand (rayon, crossbeam, parking_lot, dashmap, flume, crossbeam-channel, arc-swap, async-channel, papaya, moka); one appears when we have 80+ days of crates.io data for it. Ranked by real downloads a day (quiet-day median, release-day spikes removed), crates.io data Oct 24, 2026. The default pick is the top crate that shipped a release in the last 2 years. Downloads measure use, not quality, and crates that other libraries pull in rank above tools you add yourself: read each description for fit.
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