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Cybersecurity · head to head

Cosign vs Depot

Cosign logo

Cosign

Cybersecurity

Signs and verifies container images and artifacts, with or without managing keys

From
Free
Free plan
Yes
Full reviewWebsite
Depot logo

Depot

Developer Tools

Cloud-based builds and CI runs 55x faster with less cost

From
Free
Free plan
Yes
Full reviewWebsite

The short version

  • Each has a real cost: Cosign keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.; Depot developer plan minute limits may be insufficient for active development
  • They diverge on capability: Cosign covers Keyless signing, Depot covers Depot CI.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Cosign and Depot actually diverge.

Attributes where Cosign and Depot differ
AttributeCosignDepot
Pricing modelOpen source, no licence feeUnknown
PlatformsmacOS, Linux, Windows, DockerCloud, GitHub, CLI
CategoryCybersecurityDeveloper Tools
FoundedUnknown2022

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Cosign

  • Keyless signing
  • Key and KMS signing
  • Registry-native storage
  • In-toto attestations
  • Offline verification
  • Trusted root and signing config

Only in Depot

  • Depot CI
  • Container builds
  • GitHub Actions runners
  • Distributed caching
  • Build API
  • Depot Registry
  • Cross-platform builds
  • SSH debugging

What people use each for

The jobs each tool is most often brought in to do.

Cosign

  • Signing container images in a build pipeline without managing long-lived private keysnot Depot
  • Attaching a signed bill of materials to a release so consumers can verify its provenancenot Depot
  • Meeting a customer or regulatory requirement for signed artifactsnot Depot
  • Verifying third-party images before they enter an internal registrynot Depot

Depot

  • Accelerating Docker builds for container-based developmentnot Cosign
  • Replacing GitHub Actions runners with faster infrastructurenot Cosign
  • Distributing cache across Monorepo buildsnot Cosign
  • Debugging failed CI builds interactively with SSHnot Cosign

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Cosign

  • Keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.
  • A signature proves who signed, never whether they should have. The documentation is explicit that Sigstore cannot determine authorisation, so every consumer must write and maintain their own identity and issuer policy or verification means nothing.
  • Nothing is enforced without an admission controller. Signing changes what you can prove, not what runs, and the official policy controller has a small maintainer base for a component sitting in a cluster admission path.
  • Upgrades break pipelines. Version 3 changed defaults, version 4 is announced as removing legacy functionality and roughly half the command line flags, and two official client libraries still lacked support for the new log format as of mid 2026.
  • Signatures do not expire. An artifact signed before a maintainer account was compromised and one signed after are indistinguishable unless somebody is actively monitoring the transparency log, and almost nobody is.

Depot

  • Developer plan minute limits may be insufficient for active development
  • Startup plan at $200/mo is expensive for smaller teams
  • Business plan requires custom pricing consultation
  • macOS M2 runners not available on Developer plan

Pricing, plan by plan

Cosign

Free
  • CosignFree
    • Apache-2.0
    • Public Sigstore infrastructure free to use
    • No usage limits published

Depot

Free
  • Developer$20/month
    • 1 user
    • 500 Docker build minutes per month
    • 2,000 Depot CI minutes per month
  • Startup$200/month
    • Unlimited users
    • 5,000 Docker build minutes per month
    • 20,000 Depot CI minutes per month
  • Business$undefined/custom
    • Custom pricing
    • Unlimited users
    • Custom monthly compute

Which should you pick?

Choose Cosign if

  • You need keyless signing.
  • You want to start without paying.
  • You work on macOS, Linux, Windows, Docker.
  • You also want key and kms signing.
Cosign review

Choose Depot if

  • You need depot ci.
  • You want to start without paying.
  • You work on Cloud, GitHub, CLI.
  • You also want container builds.
Depot review

Questions people ask

Is Cosign or Depot better?
Neither clearly leads. Cosign starts at Free and Depot at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Cosign or Depot?
Cosign starts at Free and Depot at Free.
Does Cosign or Depot run on more platforms?
Cosign runs on macOS, Linux, Windows, Docker. Depot runs on Cloud, GitHub, CLI.
Can I use Cosign for free?
Both have a free tier, so you can try either at no cost before committing.
What is Cosign best used for?
Cosign is most often used for signing container images in a build pipeline without managing long-lived private keys, attaching a signed bill of materials to a release so consumers can verify its provenance, meeting a customer or regulatory requirement for signed artifacts, verifying third-party images before they enter an internal registry. Of those, signing container images in a build pipeline without managing long-lived private keys and attaching a signed bill of materials to a release so consumers can verify its provenance are not what Depot is typically brought in for.
What can Cosign do that Depot cannot?
Cosign covers Keyless signing, Key and KMS signing, Registry-native storage, In-toto attestations. Depot covers Depot CI, Container builds, GitHub Actions runners, Distributed caching.

Answered from the vendors’ own pages

Cosign: Does Cosign tell me if an image is vulnerable?

No. It has no vulnerability knowledge whatsoever. It can carry an SBOM as a signed attestation but never reads it. Pair it with a scanner.

Depot: How much faster are Depot runners compared to GitHub Actions?

Depot runners offer 30% faster CPUs and 10x faster networking than standard GitHub-hosted runners, enabling builds to complete significantly faster.

Source
Cosign: Is signing alone enough?

No. Verification is a command somebody runs. Without an admission controller enforcing it, an unsigned image still runs.

Depot: What is included in the Developer plan?

Developer plan ($20/month) includes 500 Docker build minutes, 2,000 Depot CI minutes, 2,000 GitHub Actions minutes, 25 GB storage, unlimited concurrency, and community support.

Source
Cosign: What does a bare cosign verify actually prove?

Very little. Without a pinned certificate identity and OIDC issuer, it accepts a valid signature from any identity at all.

Depot: Can I use Depot with my own AWS account?

Yes, Depot Managed allows deployment within customer AWS accounts. This is available to interested customers; contact sales for details.

Source
Cosign: What is the risk of keyless signing?

Your OIDC provider becomes the root of trust. Compromise of that account yields genuine, verifiable signatures, so account security is the control that matters.

Cosign: Should we expect breaking changes?

Yes. Version 4 is announced to remove roughly half the flags, and a post-quantum migration is named as a further breaking change after that.

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