Bytesafe vs Chainsaw

Questions and answers

As of 30 October 2026. Bytesafe facts come from Bytesafe’s own site and docs, listed under Sources.

What is Bytesafe Dependency Firewall?

Bytesafe Dependency Firewall is a policy checkpoint between package managers and public registries, built by Bitfront AB in Sweden (bytesafe.dev). Developers and CI install through a firewall endpoint instead of npmjs.org or PyPI, and each endpoint proxies one ecosystem (Bytesafe docs). Rules decide whether each request is served or blocked. Bytesafe’s selector functions cover vulnerabilities by CVSS and EPSS, malware, install scripts, deprecated releases, licences, leaked secrets on publish and npm trust downgrades (selector reference). A delay rule hides new versions for a set window, and the dashboard prefills 7 days (delay docs). Supported clients span npm, PyPI, Maven, NuGet, Go, Cargo, Composer, RubyGems, Conda and container images (ecosystems). Bytesafe hosts no packages of its own and can sit in front of or beside Artifactory or Nexus. The current generation first shipped in July 2026, and the release notes show monthly updates through October 2026.

How do Bytesafe and Chainsaw differ?

Bytesafe and Chainsaw are both registry proxies on the install path, so the differences are deployment, signals, local tooling and what you can read. First, both sit in front of public registries or an existing Artifactory or Nexus. Bytesafe Cloud runs as EU-hosted SaaS, and the Enterprise plan adds Managed Cloud, BYO Cloud or On-Premise (Bytesafe pricing). Bytesafe’s pages don’t say whether On-Premise runs without internet access. Chainsaw runs as SaaS, in your VPC, self-hosted or fully air-gapped. Chainsaw covers 16 package ecosystems and evaluates up to all 25 supply-chain signals on npm and PyPI. Chainsaw also ships a free CLI guard: a shell hook for npm, pip, cargo, gem and go that works offline. Bytesafe’s bsfw CLI is MIT-licensed on GitHub and manages firewall configuration through the dashboard’s API (CLI docs). Chainsaw’s decision engine, chainsaw-core, is open source under Apache-2.0. Bytesafe’s docs don’t say whether its rule engine is published.

How is each one priced?

Bytesafe: Cloud starts at €99 a month and is priced on whichever meter you use most: active users, packages scanned or downloads served. The base covers 10 users, 5,000 packages and 250,000 downloads. An introductory offer takes 50% off the base fee for 3 months. There is a 14-day trial and no permanently free tier. Enterprise is custom (Bytesafe pricing).

Chainsaw: Free for the local guard with no account, or hosted for 3 people. Team is $25 per seat per month. Enterprise starts at $36,000 a year.

Where is Bytesafe stronger?

• Publish-side checks. The secrets selector scans published artifacts for leaked credentials in several hundred formats, and malware checks run on upload as well as download.
• Containers under the same rules. Docker and OCI images pass the same rules as packages, every layer scanned (beta, on request).
• After-the-fact alerts. Packages served in the last 30 days are rechecked daily against advisory and malware data, with email or webhook alerts.
• Exception workflow. Developers can request an exception from a blocked install, every request is audit-logged, and exceptions carry a reason and optional expiry.
• Security fixes skip the delay. A “vulnerability fixes” exception lets a release that fixes a known advisory pass the delay rule, on eight ecosystems.
• EU residency and history. Cloud is EU-hosted; Bitfront has built supply-chain tools since 2018.

For an EU-hosted service with publish-side scanning and container coverage, Bytesafe is a strong choice.

When should you choose Chainsaw instead?

Choose Chainsaw when developers need protection before anyone opens an account, or when your security team wants to read the code that refuses a package. First, the Chainsaw CLI guard is free, needs no account, and works offline with seeds embedded in the binary. Running chainsaw guard update pulls the full public OpenSSF malicious-packages feed. Bytesafe’s pricing page lists a 14-day trial and no permanently free tier. Chainsaw’s decision engine is open source under Apache-2.0 at github.com/chain305/chainsaw-core, so a reviewer can read the refusing function before routing installs through it. Chainsaw evaluates up to all 25 signals on npm and PyPI, 22 on RubyGems, and at least 4 on every proxied ecosystem across 16. Five seeded rules block from day one, including CISA KEV entries and install scripts that fetch remote URLs. Chainsaw also publishes per-attack results for 58 supply-chain attacks from 2026.

How do you test Bytesafe and Chainsaw on your own dependencies?

The fairest test is a two-week run of both on the same lockfiles, comparing what each would have refused. Bytesafe offers a 14-day trial with the full capability set, started from its signup page. Chainsaw starts every rule in monitor mode, which records what the rule would refuse without refusing anything. Point one CI job at the Bytesafe endpoint and a second job at Chainsaw, then install the same lockfile through each. Compare three things: packages only one tool refused, the reason each tool gave, and how long an exception took to approve. Expect differences on new releases: a version published yesterday may be hidden by Bytesafe’s 7-day delay rule and held by Chainsaw’s 48-hour release hold, then released by each on a different day. Bytesafe logs every rule match with a request ID, so each refusal can be traced. After the comparison, Chainsaw rules move from monitor to enforce one at a time.

Sources

• Bytesafe, homepage and pricing.
• Bytesafe Docs, Dependency Firewall overview, What is a dependency firewall?, Ecosystems, Selector functions, Delay new versions, CLI and Release notes.