Softwr

Cloud · head to head

Cilium vs Formance

Cilium logo

Cilium

Cloud

eBPF-based networking, observability and security for Kubernetes

From
Free
Rated
-
Full reviewWebsite
Formance logo

Formance

APIs

Open source double-entry ledger and payment orchestration for money-moving software

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Cilium requires a recent Linux kernel, which rules out older distributions and some managed environments; Formance formance holds no money and provides no regulatory cover, so it must be paired with a payments provider or bank, and buyers occasionally mistake a ledger for a treasury system and discover the gap late.
  • They diverge on capability: Cilium covers eBPF datapath, Formance covers Double-entry ledger.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Cilium and Formance actually diverge.

Attributes where Cilium and Formance differ
AttributeCiliumFormance
PlatformsKubernetes, LinuxLinux, Docker, Kubernetes, Web, API
CategoryCloudAPIs

Identical on both: starting price (Free), pricing model (Open source, no licence fee), 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 Cilium

  • eBPF datapath
  • Identity-based policy
  • Hubble observability
  • Sidecar-free mesh

Only in Formance

  • Double-entry ledger
  • Numscript transaction DSL
  • Multi-currency
  • Payments connectivity
  • Reconciliation
  • Self-hosted deployment
  • Cloud offering
  • API and SDKs

What people use each for

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

Cilium

  • Kubernetes networking at a scale where iptables-based CNI performance degradesnot Formance
  • Network policy expressed on workload identity rather than fragile IP rulesnot Formance
  • Seeing which services actually talk to each other, and what policy is droppingnot Formance

Formance

  • A marketplace splitting a single customer payment between seller, platform fee and tax that needs the split to be atomic and auditablenot Cilium
  • A fintech whose homegrown balances table produced numbers finance could not reconcile and now needs proper double-entry before an auditnot Cilium
  • A payments team that wants one normalised model across several PSPs so reconciliation is not written separately for eachnot Cilium
  • A company that wants its ledger under a licence it can keep running even if the vendor disappearsnot Cilium

Where each one falls short

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

Cilium

  • Requires a recent Linux kernel, which rules out older distributions and some managed environments
  • eBPF is genuinely hard to debug when it misbehaves, and the skill is rare on most teams
  • Broad scope — CNI, policy, mesh, observability — means the learning curve covers several domains at once

Formance

  • Formance holds no money and provides no regulatory cover, so it must be paired with a payments provider or bank, and buyers occasionally mistake a ledger for a treasury system and discover the gap late.
  • Numscript is a domain-specific language your team must learn, and while it makes complex splits expressible it also means transaction logic sits outside the languages your engineers already debug well.
  • Self-hosting a ledger that must never lose or duplicate a transaction is a serious operational commitment covering backups, upgrades and Postgres tuning, which is real cost the zero licence fee hides.
  • Enterprise pricing is not published, so the difference between the free path and the supported path cannot be evaluated without a sales conversation.
  • The company is much smaller than the incumbent alternatives, and while the MIT licence protects the code it does not protect the roadmap, so features on the hosted side may arrive slowly or change direction.

Pricing, plan by plan

Cilium

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

Formance

Free
  • Open SourceFree
    • MIT licensed core ledger
    • Numscript transaction DSL
    • Multi-currency tracking
  • Enterprise$undefined/year
    • Managed or private deployment
    • Payments connectivity and reconciliation
    • Support with response commitments

Which should you pick?

Choose Cilium if

  • You need ebpf datapath.
  • You want to start without paying.
  • You work on Kubernetes, Linux.
  • You also want identity-based policy.
Cilium review

Choose Formance if

  • You need double-entry ledger.
  • You want to start without paying.
  • You work on Linux, Docker, Kubernetes, Web, API.
  • You also want numscript transaction dsl.
Formance review

Questions people ask

Is Cilium or Formance better?
Neither clearly leads. Cilium starts at Free and Formance at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Cilium or Formance?
Cilium starts at Free and Formance at Free.
Does Cilium or Formance run on more platforms?
Cilium runs on Kubernetes, Linux. Formance runs on Linux, Docker, Kubernetes, Web, API.
Can I use Cilium for free?
Both have a free tier, so you can try either at no cost before committing.
What is Cilium best used for?
Cilium is most often used for kubernetes networking at a scale where iptables-based cni performance degrades, network policy expressed on workload identity rather than fragile ip rules, seeing which services actually talk to each other, and what policy is dropping. Of those, kubernetes networking at a scale where iptables-based cni performance degrades and network policy expressed on workload identity rather than fragile ip rules are not what Formance is typically brought in for.
What can Cilium do that Formance cannot?
Cilium covers eBPF datapath, Identity-based policy, Hubble observability, Sidecar-free mesh. Formance covers Double-entry ledger, Numscript transaction DSL, Multi-currency, Payments connectivity.

Answered from the vendors’ own pages

Cilium: Is Cilium free?

Yes, open source and CNCF-graduated. Isovalent sells an enterprise distribution and support.

Formance: Is Formance really open source?

Yes. The core ledger is MIT licensed with full source access and no deployment restrictions.

Cilium: What does eBPF change?

It lets Cilium run packet-processing programs inside the kernel instead of relying on iptables rule chains, which behave poorly as the number of services grows.

Formance: Does Formance move money?

No. It records and orchestrates movements; the actual payments happen at a PSP or bank you connect.

Cilium: Does Cilium replace a service mesh?

It can cover much of what a mesh does without sidecars, though full mesh feature sets still favour Istio or Linkerd.

Formance: What does the enterprise version cost?

Not published. It is an annual subscription quoted per customer.

Formance: Do I have to use Numscript?

Yes for anything beyond the simplest transfers. It is how multi-party transactions are expressed atomically.

Share

Related pages

More on Cilium

More on Formance

Keep looking

Other head to heads