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Cybersecurity · head to head

Cosign vs Plane

Cosign logo

Cosign

Cybersecurity

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

From
Free
Rated
-
Full reviewWebsite
Plane logo

Plane

Technology

Open-source project management tool

From
Free
Rated
-
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.; Plane self-hosted Community edition requires managing your own Docker/Kubernetes infra plus your own PostgreSQL, Redis, and S3-compatible/GCS/MinIO storage; no single-binary install
  • They diverge on capability: Cosign covers Keyless signing, Plane covers Issue tracking.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Cosign and Plane actually diverge.

Attributes where Cosign and Plane differ
AttributeCosignPlane
Pricing modelOpen source, no licence feefreemium
PlatformsmacOS, Linux, Windows, DockerWeb, iOS, Android, macOS, Windows
CategoryCybersecurityTechnology
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 Plane

  • Issue tracking
  • Cycles (Sprints)
  • Modules
  • Views & layouts
  • Pages (Docs)
  • Analytics
  • API access
  • Webhooks

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 Plane
  • Attaching a signed bill of materials to a release so consumers can verify its provenancenot Plane
  • Meeting a customer or regulatory requirement for signed artifactsnot Plane
  • Verifying third-party images before they enter an internal registrynot Plane

Plane

  • Project and task management with cycles, modules, epics, and initiativesnot Cosign
  • Documentation and knowledge management via workspace wiki tied to project worknot Cosign
  • Sprint planning and issue triagenot Cosign
  • Cross-functional collaboration with analytics and dashboardsnot Cosign
  • Migration target from Jira, Linear, Monday, ClickUp, or Asananot 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.

Plane

  • Self-hosted Community edition requires managing your own Docker/Kubernetes infra plus your own PostgreSQL, Redis, and S3-compatible/GCS/MinIO storage; no single-binary install
  • Cloud Free tier caps at 12 users and 500 AI credits per seat per month
  • Substantial feature gating by tier: custom work item types, workspace wiki, time tracking, dashboards, initiatives, teamspaces, and integrations require Pro or above; LDAP, granular access control, and multi-workflow approvals require Enterprise Grid
  • Guest-to-paid-member ratio capped at 1:5 on the Pro plan

Pricing, plan by plan

Cosign

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

Plane

Free
  • FreeFree
    • 500 AI credits per seat
    • Max 12 users
    • Unlimited projects
  • Pro$6/seat per month
    • 1,000 AI credits per seat
    • Unlimited users
    • Custom work item types
  • Business$13/seat per month
    • 2,000 AI credits per seat
    • Unlimited users
    • Project templates, recurring work items
  • Enterprise Grid$null/mo
    • Flexible AI credit allocation
    • Private deployments
    • Granular access control

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 Plane if

  • You need issue tracking.
  • You want to start without paying.
  • You work on Web, iOS, Android, macOS, Windows.
  • You also want cycles (sprints).
Plane review

Questions people ask

Is Cosign or Plane better?
Neither clearly leads. Cosign starts at Free and Plane at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Cosign or Plane?
Cosign starts at Free and Plane at Free.
Does Cosign or Plane run on more platforms?
Cosign runs on macOS, Linux, Windows, Docker. Plane runs on Web, iOS, Android, macOS, Windows.
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 Plane is typically brought in for.
What can Cosign do that Plane cannot?
Cosign covers Keyless signing, Key and KMS signing, Registry-native storage, In-toto attestations. Plane covers Issue tracking, Cycles (Sprints), Modules, Views & layouts.

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.

Plane: Does Plane offer a free plan?

Yes, Plane's free tier includes 500 AI credits per seat, support for up to 12 users, and access to projects, work items, cycles, modules, layouts, views, estimates, and pages.

Source
Cosign: Is signing alone enough?

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

Plane: How much does Plane Pro cost?

Plane Pro costs $6/seat per month and saves 25% when billed annually. It includes 1,000 AI credits per seat, unlimited users, and access to custom work item types, wiki, time tracking, and integrations.

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.

Plane: What is the difference between Plane's paid tiers?

Pro ($6/seat/month) includes 1,000 AI credits and workspace wiki. Business ($13/seat/month) adds 2,000 AI credits, project templates, and recurring work items. Enterprise Grid offers custom pricing with multiple workflows and LDAP support.

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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