# rand_chacha vs rand_core

| Attribute | rand_chacha | rand_core |
|---|---|---|
| **Vioscale score** | 60.2 (22% (low)) | 43.5 (17% (low)) |
| activity.commits_last_30d | 5 | 2 |
| adoption.dependent_repos | 86,804 | 73,473 |
| adoption.github_stars | 2,068 | 13 |
| content.faq | `[{"answer":"rand_chacha is a random number generation library for the Rust programming language that implements the ChaCha algorithm. It enables Rust applications to generate random numbers.","source":"https://rust-random.github.io/book","question":"What is rand_chacha?","confidence":0.95},{"answer":"Yes, rand_chacha is open-source software and is available at no cost. There are no licensing fees or subscription costs.","source":"https://rust-random.github.io/book","question":"Is rand_chacha free to use?","confidence":0.98},{"answer":"As an open-source project, rand_chacha's source code is publicly available for review, study, and modification according to its open-source license terms.","source":"https://rust-random.github.io/book","question":"Can I view and modify the source code?","confidence":0.95},{"answer":"rand_chacha is designed specifically for the Rust programming language. It integrates with Rust's random number generation ecosystem.","source":"https://rust-random.github.io/book","question":"What programming language does rand_chacha support?","confidence":0.98},{"answer":"Documentation is available on the project's official website. Developers can consult these resources when implementing the library in their projects.","source":"https://rust-random.github.io/book","question":"Where can I find documentation for rand_chacha?","confidence":0.92},{"answer":"Yes, as open-source software, rand_chacha can be used in commercial applications. There are no licensing fees, though users should review the project's license terms for any specific requirements.","source":"https://rust-random.github.io/book","question":"Can I use rand_chacha in commercial projects?","confidence":0.95}]` | `[{"answer":"rand_core is a Rust library that provides core traits and tools for implementing random number generation functionality. It serves as a foundation for developers who are building their own randomness solutions and libraries within the Rust ecosystem.","source":"https://rust-random.github.io/book","question":"What is rand_core?","confidence":0.95},{"answer":"rand_core is open-source software available at no cost. There are no subscription fees, licensing charges, or usage restrictions for using the library.","source":"https://rust-random.github.io/book","question":"What is the cost and licensing model?","confidence":1},{"answer":"rand_core is designed for Rust developers who need to implement random number generation capabilities in their projects or libraries. It provides the essential traits and foundational tools required to build such implementations.","source":"https://rust-random.github.io/book","question":"Who should use rand_core?","confidence":0.9},{"answer":"The project includes a quick start guide, an overview of available features, and contributor documentation. These resources support both users getting started with the library and developers interested in contributing.","source":"https://rust-random.github.io/book","question":"What documentation is provided?","confidence":0.95},{"answer":"Yes, rand_core welcomes community contributions. The project provides dedicated contributor documentation to guide developers interested in participating in its development.","source":"https://rust-random.github.io/book","question":"Can developers contribute to the project?","confidence":0.9},{"answer":"rand_core is built specifically for the Rust programming language. It integrates with Rust's type system and ecosystem to provide traits and tools for random number generation implementations.","source":"https://rust-random.github.io/book","question":"What programming language does rand_core target?","confidence":0.85}]` |
| description.long | A Rust library providing ChaCha pseudo-random number generation for cryptographic and general-purpose use cases. Integrated into the Rust random ecosystem as part of the broader rand crate. | An open-source Rust library providing foundational traits for implementing random number generation algorithms. It supplies the core interfaces that RNG implementations build on, along with helper utilities for algorithm development. |
| language.primary | Rust | Rust |
| license.spdx | - | Apache-2.0 |
| market.availability | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true}` | - |
| pricing | `{"type":"open_source","freeTier":true,"sourceUrl":"https://rust-random.github.io/book","retrievedAt":"2026-08-14T11:07:29.756Z"}` | `{"type":"open_source","sourceUrl":"https://rust-random.github.io/book","retrievedAt":"2026-08-14T11:10:14.361Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | open_source | open_source |
| pricing.price_level | free | free |
| pricing.transparent | yes | - |
| release.cadence_days | 9 | 71 |
| release.history | `[{"url":"https://github.com/rust-random/rand/releases/tag/0.8.8","date":"2026-08-25T07:58:45Z","type":"stable","version":"0.8.8"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.5","date":"2026-07-11T11:19:03Z","type":"stable","version":"0.9.5"},{"url":"https://github.com/rust-random/rand/releases/tag/0.8.7","date":"2026-07-11T11:19:28Z","type":"stable","version":"0.8.7"},{"url":"https://github.com/rust-random/rand/releases/tag/0.10.2","date":"2026-07-02T09:02:44Z","type":"stable","version":"0.10.2"},{"url":"https://github.com/rust-random/rand/releases/tag/0.8.6","date":"2026-04-17T06:44:06Z","type":"stable","version":"0.8.6"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.4","date":"2026-04-13T15:42:39Z","type":"stable","version":"0.9.4"},{"url":"https://github.com/rust-random/rand/releases/tag/0.10.1","date":"2026-04-13T15:43:08Z","type":"stable","version":"0.10.1"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.3","date":"2026-04-13T15:42:08Z","type":"stable","version":"0.9.3"},{"url":"https://github.com/rust-random/rand/releases/tag/0.10.0","date":"2026-02-14T07:28:28Z","type":"stable","version":"0.10.0"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.2","date":"2026-04-13T15:41:30Z","type":"stable","version":"0.9.2"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.1","date":"2025-04-17T14:40:57Z","type":"stable","version":"0.9.1"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.0","date":"2025-01-27T13:41:24Z","type":"stable","version":"0.9.0"},{"url":"https://github.com/rust-random/rand/releases/tag/0.9.0-alpha.0","date":"2024-02-18T17:53:46Z","type":"prerelease","version":"0.9.0-alpha.0"},{"url":"https://github.com/rust-random/rand/releases/tag/rand_distr-0.5.0-alpha.0","date":"2024-02-18T17:56:14Z","type":"prerelease","version":"rand_distr-0.5.0-alpha.0"}]` | `[{"url":"https://github.com/rust-random/rand_core/releases/tag/v0.10.1","date":"2026-04-13T15:37:40Z","type":"stable","version":"v0.10.1"},{"url":"https://github.com/rust-random/rand_core/releases/tag/v0.10.0","date":"2026-02-01T09:09:36Z","type":"stable","version":"v0.10.0"}]` |
| reliability.status_page | yes | yes |
| security.scorecard | 6.2 | - |
| security.vulnerabilities | `{"count":1,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=cargo&package_name=rand&per_page=100","last_12m":1,"max_severity":"LOW"}` | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=cargo&package_name=rand_core&per_page=100","last_12m":0,"max_severity":"CRITICAL"}` |

*Source: Vioscale. Generated 2026-09-01T15:13:42.584Z. "-" = undocumented, not absent.*