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Cloud · head to head

K3s vs VerneMQ

K3s logo

K3s

Cloud

Lightweight certified Kubernetes distribution in a single binary

From
Free
Rated
-
Full reviewWebsite
VerneMQ logo

VerneMQ

Databases

Erlang MQTT broker whose source is Apache 2.0 but whose official binaries need a paid subscription

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: K3s the SQLite default is single-server only; highly available control planes need etcd or an external datastore, which removes much of the simplicity; VerneMQ the official binaries and Docker images are not Apache 2.0 but sit under a EULA requiring a yearly commercial subscription, a distinction easy to miss and awkward to discover during a licence audit.
  • They diverge on capability: K3s covers Single binary, VerneMQ covers Erlang/OTP clustering.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which K3s and VerneMQ actually diverge.

Attributes where K3s and VerneMQ differ
AttributeK3sVerneMQ
Pricing modelOpen source, no licence feequote
PlatformsLinux, ARM, Self-hostedLinux, Docker, macOS, Kubernetes
CategoryCloudDatabases

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 K3s

  • Single binary
  • SQLite by default
  • Certified conformant
  • Batteries included
  • Low resource footprint
  • Simple install

Only in VerneMQ

  • Erlang/OTP clustering
  • MQTT 5.0 support
  • Plugin system
  • Backpressure handling
  • Bridge support
  • Metrics export
  • MQTT over WebSockets
  • Pluggable auth backends

What people use each for

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

K3s

  • Kubernetes on edge sites and IoT hardware where full clusters will not fitnot VerneMQ
  • Development and CI clusters that must start fast and cost nothingnot VerneMQ
  • Small production clusters where full Kubernetes is more operations than the workload justifiesnot VerneMQ
  • Teaching and learning Kubernetes without cloud spendnot VerneMQ

VerneMQ

  • An industrial operator that wants an MQTT broker with predictable memory behaviour and no data integration features it will not usenot K3s
  • A team building from source to stay strictly under Apache 2.0 terms with no vendor licence entanglementnot K3s
  • A deployment needing custom authentication logic implemented as a plugin in Lua or over a webhooknot K3s
  • An organisation that wants a broker maintained by a small European company rather than by a vendor that keeps changing licencesnot K3s

Where each one falls short

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

K3s

  • The SQLite default is single-server only; highly available control planes need etcd or an external datastore, which removes much of the simplicity
  • Bundled components such as Traefik are opinionated defaults that larger teams often strip out and replace
  • Removed in-tree cloud provider integrations mean cloud-specific features need external controllers
  • Aimed at small and edge clusters, so very large deployments are better served by a standard distribution

VerneMQ

  • The official binaries and Docker images are not Apache 2.0 but sit under a EULA requiring a yearly commercial subscription, a distinction easy to miss and awkward to discover during a licence audit.
  • Octavo Labs is a very small company, so support depth, response times and the bus factor on the codebase are materially thinner than at HiveMQ or EMQ.
  • There is no data integration or rule engine layer, so routing messages into a database means writing and operating your own consumer service.
  • Operating an Erlang cluster requires runtime knowledge that most teams do not have and will use for nothing else in their stack.
  • There is no vendor-managed cloud offering, so every deployment is self-operated with the infrastructure and on-call cost that implies.

Pricing, plan by plan

K3s

Free
  • K3sFree
    • Full functionality
    • No usage limits
    • Community support

VerneMQ

Free
  • Source buildFree
    • Apache 2.0 licensed source from GitHub
    • Full clustering and plugin capability
    • You compile and package it yourself
  • Binary packages and Docker images$undefined/year
    • Covered by the VerneMQ EULA, not Apache 2.0
    • Yearly usage subscription expected for commercial use
    • Official builds and Docker images
  • Commercial support$undefined/year
    • Evaluation, customisation and operations assistance
    • Custom development
    • Long-term maintenance agreements

Which should you pick?

Choose K3s if

  • You need single binary.
  • You want to start without paying.
  • You work on Linux, ARM, Self-hosted.
  • You also want sqlite by default.
K3s review

Choose VerneMQ if

  • You need erlang/otp clustering.
  • You want to start without paying.
  • You work on Linux, Docker, macOS, Kubernetes.
  • You also want mqtt 5.0 support.
VerneMQ review

Questions people ask

Is K3s or VerneMQ better?
Neither clearly leads. K3s starts at Free and VerneMQ at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, K3s or VerneMQ?
K3s starts at Free and VerneMQ at Free.
Does K3s or VerneMQ run on more platforms?
K3s runs on Linux, ARM, Self-hosted. VerneMQ runs on Linux, Docker, macOS, Kubernetes.
Can I use K3s for free?
Both have a free tier, so you can try either at no cost before committing.
What is K3s best used for?
K3s is most often used for kubernetes on edge sites and iot hardware where full clusters will not fit, development and ci clusters that must start fast and cost nothing, small production clusters where full kubernetes is more operations than the workload justifies, teaching and learning kubernetes without cloud spend. Of those, kubernetes on edge sites and iot hardware where full clusters will not fit and development and ci clusters that must start fast and cost nothing are not what VerneMQ is typically brought in for.
What can K3s do that VerneMQ cannot?
K3s covers Single binary, SQLite by default, Certified conformant, Batteries included. VerneMQ covers Erlang/OTP clustering, MQTT 5.0 support, Plugin system, Backpressure handling.

Answered from the vendors’ own pages

K3s: Is K3s free?

Yes. K3s is open source with no licence fee. SUSE sells commercial support around Rancher separately.

VerneMQ: Is VerneMQ free?

The source is Apache 2.0 and free. The official binary packages and Docker images are covered by a separate EULA that expects a yearly fee for commercial use.

K3s: Is K3s real Kubernetes?

Yes. It is CNCF-certified conformant, so standard manifests, kubectl and Helm charts work without modification.

VerneMQ: Is the project still maintained?

Yes. Octavo Labs AG in Zurich continues to publish 2.x releases, most recently in 2026.

K3s: Why is K3s smaller than Kubernetes?

It strips legacy, alpha and in-tree cloud provider code, packages everything as one binary, and defaults to SQLite instead of etcd.

VerneMQ: Does it have a managed cloud?

No. Every deployment is self-hosted, with commercial support available from Octavo Labs.

K3s: Can K3s run in production?

Yes, and it does, particularly at the edge and for small clusters. For a highly available control plane you need to move off the SQLite default to etcd or an external datastore.

VerneMQ: How does it compare to EMQX?

Narrower in features and without a rule engine, but with a simpler licence story for source builds after EMQX moved to BSL.

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