Crates / zerocopy-derive
Rust crate · real downloads · data Oct 24, 2026
zerocopy-derive downloads, and should you depend on it?
Custom derive for traits from the zerocopy crate crates.io · docs.rs · repository
Few direct dependents and steady.
zerocopy-derive: only 68 crates name it directly; most of its downloads come in through zerocopy; small bumps on release days (1.18x the baseline).
How this verdict is decided (4 rules)
- Usage: crates.io reverse dependencies (crates that list it as a dependency): 10,000+ = foundational, 1,000+ = widely used, 100+ = established, under 100 = few direct dependents.
- Direction: the median quiet day in the last 30 days of the window against the first 30, read against the median tracked crate (the whole field moved +36% from late summer to October, so a raw trend says nothing). 10%+ ahead of the field = gaining; 10%+ behind = losing ground; otherwise steady. Steady with no release in 2+ years = quiet for years.
- Release spikes: the median release-window day against the quiet-day baseline: under 1.15x = no spike, 1.15x to 1.3x = small bumps, 1.3x or more = jumps on release days.
- Release recency: days since the newest version that was not yanked, from crates.io publish times.
release window (release day + next day)quiet dayquiet-day median · download the 89 days as CSV
The numbers in one paragraphzerocopy-derive got 203,354,580 crates.io downloads from Jul 27, 2026 to Oct 23, 2026. 18% of them landed within 2 days of one of its 8 releases. On the other 75 quiet days it got a median of 2,234,913 a day, about 15,644,391 a week. Capping release days at that baseline leaves 196,211,529 release-adjusted downloads for the window.
What this means if you're choosing a dependency
- You rarely add this one yourself. Only 68 crates name it directly; its downloads arrive through zerocopy.
- Actively released. 0.8.63 shipped 11 days ago (Oct 13, 2026).
- Still pre-1.0 (0.8.63). Under Cargo's semver rules a 0.x minor bump may break you, so pin the minor version (
zerocopy-derive = "0.8") and read the changelog on upgrades. - Fit check: license BSD-2-Clause OR Apache-2.0 OR MIT, edition 2021 (from the latest version's manifest).
- Compare it by the baseline, not the raw count. 18% of its 203,354,580 downloads in the window landed within 2 days of a release; the steady number is 2,234,913 a day.
Its place in the dependency graph
Built on zerocopy-derive
1 of the 300 crates we track depend on it directly (biggest first).
zerocopy-derive builds on
Tracked crates its latest version (0.8.63) depends on.
What the chart says
- Weekend quiet days ran at 62% of weekday quiet days (1,477,870 vs 2,390,794). A dip that deep is the signature of work-week CI pipelines and developers building on weekdays.
- Biggest day: 3,580,566 on Oct 21, 2026, a quiet day with no release nearby.
Every number
| All-time downloads | 700,830,298 (rank #172 on crates.io by all-time downloads) |
| Downloads in the window | 203,354,580 (Jul 27, 2026 to Oct 23, 2026, 89 days) |
| Within 2 days of a release | 37,410,103 (18.4%) |
| Quiet-day median (baseline) | 2,234,913 a day; weekdays 2,390,794, weekends 1,477,870 |
| Release-adjusted downloads | 196,211,529 (release-window days capped at the baseline) |
| Baseline rank | #161 of the 300 crates we track |
| Quiet-day trend | +33% raw, -2% against the median tracked crate (+36%) |
| Releases in the window | 8 |
| Versions published, ever | 161 |
| Latest version | 0.8.63, published Oct 13, 2026 (license BSD-2-Clause OR Apache-2.0 OR MIT, edition 2021) |
| First published | Feb 28, 2019 |
| Reverse dependencies | 68 |
Releases in the window
Each one opens a 2-day release window on the chart.
| Version | Published | Downloads that version got (lifetime) |
|---|---|---|
| 0.8.63 | Oct 13, 2026 | 4,480,803 |
| 0.8.62 | Oct 8, 2026 | 3,402,262 |
| 0.8.61 | Oct 7, 2026 | 940,321 |
| 0.8.60 | Oct 5, 2026 | 806,035 |
| 0.8.59 | Sep 25, 2026 | 7,470,666 |
| 0.8.58 | Sep 24, 2026 | 1,102,877 |
| 0.8.57 | Sep 8, 2026 | 10,619,414 |
| 0.8.56 | Aug 6, 2026 | 26,407,498 |
How we compute this
crates.io counts every download, including CI runners, mirrors and bots that fetch each new version, so raw counts run high (why, in The Manual). We split the last 89 days into release windows (the day a version of zerocopy-derive was published, plus the next day) and quiet days, and use the median quiet day as the baseline: an upper bound on steady use, never a head count. The method and data come from our study of 90 days of crates.io data from 69 crates, featured in This Week in Rust #674; check any crate live with the real-downloads checker.
Badge for your README
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Categories
Sources
- Daily downloads: crates.io API, /crates/zerocopy-derive/downloads (last 90 days, all versions), fetched Oct 24, 2026.
- Versions and publish times: crates.io API, /crates/zerocopy-derive/versions, same fetch.
- Reverse dependencies: crates.io reverse dependencies, same fetch. Dependency edges between tracked crates: each crate's default version, crates.io API.
- Fetched politely (one request every 2 seconds, identified User-Agent) per the crates.io data access policy. Data is crates.io's; the release-window split, baseline and verdict rules are ours, CC BY 4.0.