Crates / Compare / static_assertions vs arbitrary
Rust crates side by side · data Oct 24, 2026
static_assertions vs arbitrary
Short answerBy steady daily use, static_assertions is bigger: 1,442,265 real downloads a day against 574,083 for arbitrary (2.5x). 1,688 crates depend on static_assertions and 1,030 on arbitrary. static_assertions last shipped 7.0 years ago, arbitrary 18 days ago.
static_assertions
Widely usedWidely used and quiet for years.
1,688 crates depend on it; no release in the last 90 days, so its count is all steady use.
Compile-time assertions to ensure that invariants are met.
arbitrary
Widely usedWidely used and steady.
1,030 crates depend on it; small bumps on release days (1.27x the baseline).
The trait for generating structured data from unstructured data
static_assertionsarbitrary · 100% = that crate's normal quiet day, so a spike to 300% is triple its usual traffic
How they relate
- Often used together: 1 tracked crate depend on both (compact_str). They are not always either/or.
Every number, side by side
| Same window, same method | static_assertions | arbitrary |
|---|---|---|
| Real downloads a day | 1,442,265 | 574,083 |
| Crates that depend on it | 1,688 | 1,030 |
| Last release | 1.1.0, 7.0 years ago | 1.5.0, 18 days ago |
| Trend vs the field | +1% | -2% |
| Release-window share | 0.0% | 2.9% |
| Downloads in the window | 130,951,945 | 50,129,070 |
| All-time downloads | 561,828,019 | 184,145,936 |
| Versions published | 15 | 39 |
| License | MIT OR Apache-2.0 | MIT OR Apache-2.0 |
| MSRV | not set | 1.71.0 |
| First published | Aug 13, 2017 | May 8, 2017 |
Which to pick
- Downloads tell you what is common, not what fits. Each crate's own description above says what it is for; when the jobs differ, pick by the job.
- When both fit, prefer the one more crates depend on (static_assertions, 1,688 dependents): more eyes, more answered questions, and you may already have it in your tree.
- Check the release dates against your own pace: static_assertions 7.0 years ago, arbitrary 18 days ago.
Also in this space
Method
Real downloads = the median day with no release that day or the day before, from the crates.io API (Jul 27, 2026 to Oct 23, 2026). Raw crates.io counts include CI and bots and run high (why); the method is from our 90-day study.
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