Softwr

Web Development · head to head

Preact vs VerneMQ

Preact logo

Preact

Web Development

3kB alternative to React with the same modern API

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: Preact compatibility through preact/compat is good but not total, and some React libraries break in ways that are hard to diagnose; 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: Preact covers 3kB runtime, VerneMQ covers Erlang/OTP clustering.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Preact and VerneMQ actually diverge.

Attributes where Preact and VerneMQ differ
AttributePreactVerneMQ
Pricing modelOpen source, no licence feequote
PlatformsWebLinux, Docker, macOS, Kubernetes
CategoryWeb DevelopmentDatabases

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 Preact

  • 3kB runtime
  • preact/compat
  • Same modern API
  • Fast rendering

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.

Preact

  • Embedded widgets that load inside someone else’s page and must stay smallnot VerneMQ
  • Marketing and content sites where JavaScript payload affects Core Web Vitalsnot VerneMQ
  • Applications targeting low-bandwidth or low-powered devicesnot VerneMQ

VerneMQ

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

Where each one falls short

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

Preact

  • Compatibility through preact/compat is good but not total, and some React libraries break in ways that are hard to diagnose
  • Behavioural differences from React exist in edge cases, particularly around event handling
  • A much smaller community, so unusual problems have fewer existing answers than React

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

Preact

Free
  • PreactFree
    • Full library
    • Commercial use permitted
    • No usage limits

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 Preact if

  • You need 3kb runtime.
  • You want to start without paying.
  • You also want preact/compat.
Preact 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 Preact or VerneMQ better?
Neither clearly leads. Preact 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, Preact or VerneMQ?
Preact starts at Free and VerneMQ at Free.
Does Preact or VerneMQ run on more platforms?
Preact runs on Web. VerneMQ runs on Linux, Docker, macOS, Kubernetes.
Can I use Preact for free?
Both have a free tier, so you can try either at no cost before committing.
What is Preact best used for?
Preact is most often used for embedded widgets that load inside someone else’s page and must stay small, marketing and content sites where javascript payload affects core web vitals, applications targeting low-bandwidth or low-powered devices. Of those, embedded widgets that load inside someone else’s page and must stay small and marketing and content sites where javascript payload affects core web vitals are not what VerneMQ is typically brought in for.
What can Preact do that VerneMQ cannot?
Preact covers 3kB runtime, preact/compat, Same modern API, Fast rendering. VerneMQ covers Erlang/OTP clustering, MQTT 5.0 support, Plugin system, Backpressure handling.

Answered from the vendors’ own pages

Preact: Is Preact free?

Yes, open source under the MIT licence.

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.

Preact: Can I use React libraries with Preact?

Most, through the preact/compat layer. Compatibility is good but not complete, so libraries relying on React internals can break.

VerneMQ: Is the project still maintained?

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

Preact: Why choose Preact over React?

Bundle size, almost always. If payload is not a binding constraint, React’s ecosystem is usually the better trade.

VerneMQ: Does it have a managed cloud?

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

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.

Share

Related pages

More on Preact

More on VerneMQ

Keep looking

Other head to heads