Decision Workspace
fastvec vs smallvec vs smallvec-stableunion
Side-by-side comparison of Rust crates
50
fastvec
experimentalv1.1.0
A high-performance vector crate tuned for small data sizes.
70
smallvec
stablev1.15.1
'Small vector' optimization: store up to a small number of items on the stack
40
smallvec-stableunion
growingv0.6.10
Fork of the crate smallvec. Uses unions in stable rust. Please note that it can only store Copy types. No functional differences apart from that.
Core Metrics
| fastvec | smallvec | smallvec-stableunion | |
|---|---|---|---|
| Health Score | 50 | 70 | 40 |
| Total Downloads | 171 | 730.7M | 3.5K |
| 30d Downloads | 9 | 49.2M | 36 |
| Dependents | 0 | 51.1K | 1 |
| Releases | 9 | 76 | 1 |
| Last Updated | 48d ago | 131d ago | 2365d ago |
| Age | 3m | 10y 11m | 6y 5m |
Health Breakdown
fastvec
Maintenance
16
Quality
13
Community
3
Popularity
3
Documentation
15
smallvec
Maintenance
14
Quality
17
Community
19
Popularity
8
Documentation
12
smallvec-stableunion
Maintenance
1
Quality
18
Community
6
Popularity
4
Documentation
11
Technical Details
| fastvec | smallvec | smallvec-stableunion | |
|---|---|---|---|
| Version | 1.1.0 | 1.15.1 | 0.6.10 |
| Stable (≥1.0) | ✓ Yes | ✓ Yes | ✗ No |
| License | MIT OR Apache-2.0 | MIT OR Apache-2.0 | MIT/Apache-2.0 |
| Dependencies | 1 | 8 | 2 |
| Crate Size | 53KB | 38KB | 21KB |
| Features | 3 | 10 | 5 |
| Yanked % | 44.4% | 26.3% | 0.0% |
| Edition | 2024 | 2018 | — |
| MSRV | 1.88.0 | — | — |
| Owners | 1 | 3 (team) | 1 |
Links
Quick Verdict
- •smallvec leads with a health score of 70/100, but none of the options score above 80.
- •smallvec is depended on by 51.1K crates — strongest ecosystem trust.
- •⚠ smallvec-stableunion has not been updated in over a year.
- •smallvec-stableunion is pre-1.0 — API may change.