# Bun vs PyPI

**Leader by vioscaleAI score:** Bun

| Attribute | Bun | PyPI |
|---|---|---|
| **vioscaleAI score** | 74.2 (56% (medium)) | 51.2 (23% (low)) |
| activity.commits_last_30d | 100 | 100 |
| adoption.dependent_repos | 21,486 | 0 |
| adoption.github_stars | 96,235 | 4,166 |
| adoption.package_downloads_weekly | 3,990,852 | - |
| content.faq | `[{"answer":"Bun is a JavaScript runtime and development toolkit designed as a fast alternative to Node.js with built-in package management, testing, and bundling capabilities. It can be adopted incrementally into existing Node.js projects or used as a complete replacement for development tooling. It is indexed under Package Registries.","source":"https://bun.sh","question":"What is Bun?","confidence":0.6},{"answer":"Bun offers a free tier, so you can start without paying. Pricing changes often, so verify at source before relying on it.","source":"https://bun.sh","question":"Is Bun free?","confidence":0.6},{"answer":"Bun supports Windows, macOS, Linux and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://bun.sh","question":"What platforms does Bun support?","confidence":0.6},{"answer":"Yes. Bun can be deployed self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://bun.sh","question":"Can Bun be self-hosted?","confidence":0.6},{"answer":"Yes. Bun is published under the MIT licence, a permissive licence that generally allows commercial use and modification. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://www.npmjs.com/package/bun","question":"Is Bun open source?","confidence":0.85}]` | `[{"answer":"PyPI is the official package registry for Python, serving as a centralized platform where developers can find and install community-created software, and package authors can distribute their work. It is indexed under Package Registries.","source":"https://pypi.org","question":"What is PyPI?","confidence":0.6},{"answer":"PyPI offers a free tier, so you can start without paying. Pricing changes often, so verify at source before relying on it.","source":"https://pypi.org","question":"Is PyPI free?","confidence":0.6},{"answer":"PyPI supports the web and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://pypi.org","question":"What platforms does PyPI support?","confidence":0.6},{"answer":"Yes. PyPI can be deployed cloud / SaaS and self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://pypi.org","question":"Can PyPI be self-hosted?","confidence":0.6},{"answer":"Yes. PyPI is published under the Apache-2.0 licence, a permissive licence that generally allows commercial use and modification. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/pypa/warehouse","question":"Is PyPI open source?","confidence":0.95}]` |
| deployment.options | `{"cloud":true,"self_hosted":true}` | `{"cloud":true}` |
| description.long | A JavaScript runtime that executes TypeScript natively using JavaScriptCore, bundling a package manager, bundler, and test runner with Node.js compatibility and npm ecosystem support. | PyPI is the official package registry for Python, serving as a centralized platform where developers can find and install community-created software, and package authors can distribute their work. |
| features.capabilities | `{"role":"manager_client","ecosystem":"js","deployment":"cli_local","workspaces":true,"open_source":"oss","pricing_model":"free","upstream_proxy":true,"package_formats":"multi","private_packages":true,"content_addressable":true,"vuln_license_scanning":true,"lockfile_deterministic":true,"supply_chain_integrity":true}` | `{"role":"public_registry","ecosystem":"python","deployment":"both","open_source":"oss","pricing_model":"free","package_formats":"single"}` |
| language.primary | Rust | Python |
| license.spdx | MIT | Apache-2.0 |
| market.availability | - | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"cli":true,"mac":true,"linux":true,"windows":true}` | `{"web":true}` |
| pricing | `{"type":"open_source","summary":"Free and open source","freeTier":true,"sourceUrl":"https://bun.sh","retrievedAt":"2026-10-14T22:32:45.643Z"}` | `{"type":"free","summary":"Free to use","sourceUrl":"https://pypi.org","retrievedAt":"2026-09-14T15:32:42.238Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | open_source | free |
| pricing.price_level | free | free |
| pricing.transparent | - | yes |
| release.cadence_days | 14 | - |
| release.history | `[{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.4.3","date":"2026-10-10T05:24:54Z","type":"stable","version":"bun-v1.4.3"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.4.2","date":"2026-09-05T05:55:48Z","type":"stable","version":"bun-v1.4.2"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.4.1","date":"2026-09-04T08:33:19Z","type":"stable","version":"bun-v1.4.1"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.4.0","date":"2026-08-20T14:07:21Z","type":"stable","version":"bun-v1.4.0"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.14","date":"2026-05-13T03:48:28Z","type":"stable","version":"bun-v1.3.14"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.13","date":"2026-04-20T08:07:57Z","type":"stable","version":"bun-v1.3.13"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.12","date":"2026-04-10T03:04:46Z","type":"stable","version":"bun-v1.3.12"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.11","date":"2026-03-18T04:31:40Z","type":"stable","version":"bun-v1.3.11"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.10","date":"2026-02-26T07:08:20Z","type":"stable","version":"bun-v1.3.10"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.9","date":"2026-02-08T09:31:23Z","type":"stable","version":"bun-v1.3.9"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.8","date":"2026-01-29T10:38:16Z","type":"stable","version":"bun-v1.3.8"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.7","date":"2026-01-27T07:04:03Z","type":"stable","version":"bun-v1.3.7"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.6","date":"2026-01-13T02:27:21Z","type":"stable","version":"bun-v1.3.6"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.5","date":"2025-12-17T16:55:41Z","type":"stable","version":"bun-v1.3.5"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.4","date":"2025-12-07T04:53:19Z","type":"stable","version":"bun-v1.3.4"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.3","date":"2025-11-21T19:32:02Z","type":"stable","version":"bun-v1.3.3"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.2","date":"2025-11-08T07:57:10Z","type":"stable","version":"bun-v1.3.2"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.1","date":"2025-10-22T07:53:48Z","type":"stable","version":"bun-v1.3.1"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.3.0","date":"2025-10-10T20:32:14Z","type":"stable","version":"bun-v1.3.0"},{"url":"https://github.com/oven-sh/bun/releases/tag/bun-v1.2.23","date":"2025-09-28T14:23:34Z","type":"stable","version":"bun-v1.2.23"}]` | - |
| reliability.status_page | - | yes |
| security.disclosure_policy | - | yes |
| security.scorecard | - | 7.8 |
| security.vulnerabilities | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=npm&package_name=bun&per_page=100","last_12m":0,"max_severity":"HIGH"}` | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=go&package_name=github.com%2Fpypa%2Fwarehouse&per_page=100","last_12m":0,"max_severity":null}` |

## Capabilities (Package Registries)

| Capability | Bun | PyPI |
|---|:--:|:--:|
| **Core** |  |  |
| Role | Package manager client | Public registry |
| **Ecosystem** |  |  |
| Ecosystem / language | JavaScript | Python |
| **Deployment** |  |  |
| Deployment | CLI-local | Both |
| **Formats** |  |  |
| Package formats supported | Many formats | Single ecosystem |
| **Hosting** |  |  |
| Private / scoped packages | ✓ | - |
| Upstream proxy / caching | ✓ | - |
| **Resolution** |  |  |
| Lockfile / deterministic installs | ✓ | - |
| Workspaces / monorepo | ✓ | - |
| Content-addressable store | ✓ | - |
| **Supply chain** |  |  |
| Supply-chain integrity | ✓ | - |
| Vulnerability / licence scanning | ✓ | - |
| **Licensing** |  |  |
| Openness | Open-source | Open-source |
| **Pricing** |  |  |
| Pricing model | Free / OSS | Free / OSS |

*Source: vioscaleAI. Generated 2026-10-16T21:37:45.479Z. "-" = undocumented, not absent.*