Is this an invoice audit?

No. Cost that comes out through a negotiation goes back in within two quarters. What holds is a unit-economics model owned by the teams that spend, wired into the architecture decisions that actually move the bill — which takes a mandate rather than a report.

Where is the real proof?

In the PMU replatforming, where total cost of ownership fell 87% while a five-nines uptime target held. At Societe Generale, where a datacenter exit onto elastic AWS patterns cut TCO by 37%. At celio, where a data-mesh replatforming took 30% out of TCO while the digital business grew.

How does this relate to PerfOps and GreenOps?

They are the same dial read three ways. Rightsizing a fleet takes money and carbon out and can take the service level with it. Cost decisions are taken here, but arbitrated against the numbers held in PerfOps and GreenOps rather than against nothing.

Who should not hire this werk?

An organization that wants a saving without changing who decides. If engineering teams do not see and own their spend, the model is a spreadsheet and the bill returns.

FinOps — capability

FamilyPerformance Carried byAdvisory Carried byInterim Proven lines2 / 4 Detailed mandates3 IndustriesBanking, Betting, Fashion Retail

Werk 14 — who carries it

arms and mandates

Advisory Interim CTO COO

A cloud bill is an architecture diagram written in money. This werk reads it that way: spend mapped to the workloads that cause it, a unit cost the business recognises, and the decision moved to the engineers whose design sets the number.

The offer

what is bought, and in what shape

A cloud bill that is explained line by line against the workloads behind it, a unit-cost metric the business recognises, and the spend decisions moved into the teams that cause them.

Cost model and unit economics

Cloud spend mapped to workloads, teams and products, with a unit-cost metric — per transaction, per customer, per tenant — that the business already uses to talk about volume.

Commitment and rightsizing plan

Reserved capacity, savings plans and instance families ranked by saving against effort and lock-in, with the architecture moves that change the bill more than any discount will.

Showback and accountability

Tagging standard, allocation rules and a monthly reading the engineering teams run themselves, so cost stops being a finance report they receive.

Anomaly and drift control

Budget alerts wired to owners, drift caught in days rather than at invoice, and a written rule for what happens when a workload doubles.

Assessment3 to 6 weeks

Cost baseline, allocation model, hot-spot ranking, prioritised plan.

AdvisoryFractional authority alongside the platform team

Target unit economics, commitment strategy, arbitration on architecture spend.

Interim seat6 to 18 months, CTO or COO-adjacent

The practice stood up and the baseline moved, with the numbers sourced.

FinOps unit economicsTagging and allocationReserved capacity and savings plansRightsizingCloud cost telemetry

State of the proof

counted from the ledger below

4sub-capabilities

2proven · a published case carries a sourced figure

2held · carried by a named operator, no case published

0declared · in scope, no published proof today

Experiences that prove it

3 detailed mandates

CelioFashion RetailAn omnichannel replatforming that grew e-commerce from a 4.7% to a 7% revenue share and delivered a 46% revenue lift over an 11-month product mandate.Proves: Cloud cost engineering and FinOps · Unit economics and cost allocation PMUBettingA mainframe-to-AWS modernization that cut total cost of ownership by 87% while holding 99.995% uptime on the replatformed betting applications.Proves: Cloud cost engineering and FinOps Société GénéraleBankingA BU MassMarketing cloud migration off owned datacenters onto AWS that cut total cost of ownership by 37%.Proves: Cloud cost engineering and FinOps

Sub-capabilities and evidence

4 lines, each with its state

Cloud cost engineering and FinOpsprovenPMU Société Générale Celio

Unit economics and cost allocationprovenCelio

Commitment strategy and rightsizingheldCommitment and rightsizing programmes run inside replatforming mandates, where the saving is reported as part of the migration rather than published as a cost engagement in its own right.

Cost governance and showbackheldTagging standards and monthly cost readings stood up alongside platform teams on mandate; no case published on the governance work separately.

Publishable figures

named, sourced, attributable

-87%TCO · mainframe to AWS, betting platformPMU mandate · replatformed betting applications

-37%TCO · datacenter exit to AWSErwan Deschamps · local-entity CTO, TCS for Societe Generale BU MassMarketing

-30%TCO · data-mesh replatformingcelio mandate · data platform rebuilt while the digital business grew

Questions

answered, in the open

Is this an invoice audit?: No. Cost that comes out through a negotiation goes back in within two quarters. What holds is a unit-economics model owned by the teams that spend, wired into the architecture decisions that actually move the bill — which takes a mandate rather than a report.
Where is the real proof?: In the PMU replatforming, where total cost of ownership fell 87% while a five-nines uptime target held. At Societe Generale, where a datacenter exit onto elastic AWS patterns cut TCO by 37%. At celio, where a data-mesh replatforming took 30% out of TCO while the digital business grew.
How does this relate to PerfOps and GreenOps?: They are the same dial read three ways. Rightsizing a fleet takes money and carbon out and can take the service level with it. Cost decisions are taken here, but arbitrated against the numbers held in PerfOps and GreenOps rather than against nothing.
Who should not hire this werk?: An organization that wants a saving without changing who decides. If engineering teams do not see and own their spend, the model is a spreadsheet and the bill returns.

Related werks

same family, shared proof

Discuss a finops mandate How Advisory runs it All sixteen werks

FinOps.