Crates / ctutils
Rust crate · real downloads · data Oct 24, 2026
ctutils downloads, and should you depend on it?
Constant-time utility library with selection and equality testing support targeting cryptographic applications. Supports `const fn` where appropriate. Built on the `cmov` crate which provides architecture-specific predication intrinsics. Heavily inspired by the `subtle` crate. crates.io · docs · repository
Owned on crates.io by tarcieri · alternatives · is it still maintained?
Feature flags + Cargo.toml picker · Security history
Few direct dependents and gaining.
ctutils: only 55 crates name it directly; most of its downloads come in through digest and hybrid-array; downloads jump on release days (1.6x 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 +39% 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 paragraphctutils got 78,843,395 crates.io downloads from Jul 27, 2026 to Oct 23, 2026. 5% of them landed within 2 days of one of its 3 releases. On the other 86 quiet days it got a median of 838,314 a day, about 5,868,194 a week. Capping release days at that baseline leaves 77,109,464 release-adjusted downloads for the window.
What this means if you're choosing a dependency
- You rarely add this one yourself. Only 55 crates name it directly; its downloads arrive through digest, hybrid-array, pkcs8.
- Actively released. 0.4.5 shipped 1 day ago (Oct 23, 2026).
- Still pre-1.0 (0.4.5). Under Cargo's semver rules a 0.x minor bump may break you, so pin the minor version (
ctutils = "0.4") and read the changelog on upgrades. - Fit check: license Apache-2.0 OR MIT, edition 2024, needs Rust 1.87 or newer (from the latest version's manifest).
- Compare it by the baseline, not the raw count. 5% of its 78,843,395 downloads in the window landed within 2 days of a release; the steady number is 838,314 a day.
Alternatives that do a similar job
Crates that share its crates.io category or keywords, most similar first. Each line is the crate's own description, then how it compares on the same data.
Its place in the dependency graph
Built on ctutils
7 of the 1000 crates we track depend on it directly (biggest first).
ctutils builds on
Tracked crates its latest version (0.4.5) depends on (optional ones marked).
What the chart says
- Weekend quiet days ran at 57% of weekday quiet days (533,412 vs 929,740). A dip that deep is the signature of work-week CI pipelines and developers building on weekdays.
- Biggest day: 1,743,268 on Oct 21, 2026, a quiet day with no release nearby.
Every number
| All-time downloads | 112,819,713 (rank #866 on crates.io by all-time downloads) |
| Downloads in the window | 78,843,395 (Jul 27, 2026 to Oct 23, 2026, 89 days) |
| Within 2 days of a release | 4,248,872 (5.4%) |
| Quiet-day median (baseline) | 838,314 a day; weekdays 929,740, weekends 533,412 |
| Release-adjusted downloads | 77,109,464 (release-window days capped at the baseline) |
| Baseline rank | #431 of the 1000 crates we track |
| Quiet-day trend | +72% raw, +24% against the median tracked crate (+39%) |
| Releases in the window | 3 |
| Versions published, ever | 25 |
| Latest version | 0.4.5, published Oct 23, 2026 (license Apache-2.0 OR MIT, edition 2024, MSRV 1.87) |
| First published | Dec 18, 2025 |
| Reverse dependencies | 55 |
Releases in the window
Each one opens a 2-day release window on the chart.
| Version | Published | Downloads that version got (lifetime) |
|---|---|---|
| 0.4.5 | Oct 23, 2026 | 334,446 |
| 0.4.4 | Oct 23, 2026 | 174,491 |
| 0.4.3 | Oct 5, 2026 | 5,260,967 |
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 ctutils 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
Maintainers can show the baseline in a README. It is optional, updates when we refresh the data, and links back here. Preview, then copy:
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Publishing a crate of your own? How to publish a Rust crate to crates.io, step by step.
Categories
Sources
- Daily downloads: crates.io API, /crates/ctutils/downloads (last 90 days, all versions), fetched Oct 24, 2026.
- Versions and publish times: crates.io API, /crates/ctutils/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.
Up next
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