Crates / swc_core
Rust crate · real downloads · data Oct 27, 2026
swc_core downloads, and should you depend on it?
TBD crates.io · docs · repository
Established and losing ground.
swc_core: 117 crates depend on it; downloads don't spike on releases.
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 paragraphswc_core got 1,169,553 crates.io downloads from Jul 30, 2026 to Oct 26, 2026. 49% of them landed within 2 days of one of its 28 releases. On the other 48 quiet days it got a median of 14,276 a day, about 99,936 a week. Capping release days at that baseline leaves 1,098,928 release-adjusted downloads for the window.
What this means if you're choosing a dependency
- Used, not everywhere. 117 crates depend on it. Look at how fast its issues get answered before you lean on it.
- Actively released. 82.2.0 shipped 6 days ago (Oct 21, 2026).
- Fit check: license Apache-2.0, edition 2021 (from the latest version's manifest).
- Compare it by the baseline, not the raw count. 49% of its 1,169,553 downloads in the window landed within 2 days of a release; the steady number is 14,276 a day.
What the chart says
- Weekend quiet days ran at 36% of weekday quiet days (5,768 vs 15,835). A dip that deep is the signature of work-week CI pipelines and developers building on weekdays.
- Biggest day: 19,642 on Aug 18, 2026, inside a release window.
Every number
| All-time downloads | 6,907,822 (outside the crates.io top 1,000 by all-time downloads) |
| Downloads in the window | 1,169,553 (Jul 30, 2026 to Oct 26, 2026, 89 days) |
| Within 2 days of a release | 577,979 (49.4%) |
| Quiet-day median (baseline) | 14,276 a day; weekdays 15,835, weekends 5,768 |
| Release-adjusted downloads | 1,098,928 (release-window days capped at the baseline) |
| Baseline rank | #1124 of the 1243 crates we track |
| Quiet-day trend | -7% raw, -33% against the median tracked crate (+39%) |
| Releases in the window | 28 |
| Versions published, ever | 1,499 |
| Latest version | 82.2.0, published Oct 21, 2026 (license Apache-2.0, edition 2021) |
| First published | Aug 2, 2022 |
| Reverse dependencies | 117 |
Releases in the window
Each one opens a 2-day release window on the chart. Showing the last 12 of 28.
| Version | Published | Downloads that version got (lifetime) |
|---|---|---|
| 82.2.0 | Oct 21, 2026 | 7,137 |
| 82.1.2 | Oct 21, 2026 | 171 |
| 82.1.1 | Oct 15, 2026 | 12,621 |
| 82.1.0 | Oct 14, 2026 | 2,322 |
| 82.0.2 | Oct 11, 2026 | 2,386 |
| 82.0.1 | Oct 11, 2026 | 172 |
| 82.0.0 | Oct 6, 2026 | 9,971 |
| 81.0.2 | Sep 30, 2026 | 12,997 |
| 81.0.1 | Sep 29, 2026 | 375 |
| 81.0.0 | Sep 27, 2026 | 404 |
| 80.0.1 | Sep 23, 2026 | 1,578 |
| 80.0.0 | Sep 17, 2026 | 9,032 |
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 swc_core 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.
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Categories
Sources
- Daily downloads: crates.io API, /crates/swc_core/downloads (last 90 days, all versions), fetched Oct 27, 2026.
- Versions and publish times: crates.io API, /crates/swc_core/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
Next by real downloads: The next crate down the real-downloads ranking: 13,820 a day. Established and gaining.dioxusRust crate. Build fullstack web, desktop, and mobile apps with a single codebase. Real use: 13.8K downloads a day on quiet days; 471 crates depend on it.Read it next →Also worth your time
Art: Nicholas Roerich, Nag Lake (1925). Public domain, via Wikimedia Commons.
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