Greggs: Making a pandemic-era app team predictable, and trusted again

A rushed app launch left a technical department that the rest of the business no longer trusted. We made delivery predictable, and used data to prove that paying down tech debt made it faster.
Delivery
Rung
Scrum Master support across two squads, plus agile coaching beyond engineering.
Duration
6 months
Engagement shape
Scrum Master support across two squads, plus agile coaching beyond engineering.
Stage reachedDelivery transformation, not AI work
2squads: Mobile App and Integration
Org-wideagile coaching beyond engineering
Tech debtshown to speed up delivery, with data
On this page

The challenge

Greggs launched a mobile app so customers could order and earn rewards, but the rushed setup of technical ways of working created friction with Marketing and other departments. They needed Scrum Master support for two squads plus broader agile coaching across the business.

What we did

We refined Story Points for capacity-based tracking, coached Product on data-driven prioritisation, and ran prioritisation workshops and alignment sessions that taught non-technical teams how agile actually works. We used data to prove the payback of addressing tech debt.

// run against The Tenhaw Way, published in full and free to adopt without engaging us

The outcome

Delivery became predictable, confidence in the technical department recovered, and prioritisation conversations became realistic and focused. The data showing tech debt accelerated timelines strengthened collaboration across departments.

Limits, and what is withheld

What transfers, and what does not

Cross-functional trust and a shared, data-backed language for value are prerequisites for agentic change. Agents amplify whatever operating culture they land in, so the culture has to be sound first. What transfers from Greggs is the coaching and prioritisation discipline that made one department's numbers believable to every other one.

Context

Why a buyer usually lands on this one

Written for the person arriving mid-programme with a question.

The department nobody outside it believes

The recurring pattern here is not technical. A team ships under pressure, ways of working get invented on the way, and within a year the rest of the business treats every estimate from that department as fiction. Prioritisation then becomes a negotiation about credibility rather than about value.

AI makes this worse before it makes it better. A head of AI inheriting a department in that position will find the blocker to their programme is not the model, it is that no commitment the department makes is believed, so nothing can be sequenced.

Tech debt, argued with numbers

The claim that paying down tech debt accelerates delivery is usually made as an engineering opinion and lost as a budget conversation. We made it with throughput data instead, which is how it survived contact with Marketing.

The same argument is coming for every organisation trying to scale AI agents onto an estate whose interfaces and data are undocumented. Agents are unusually sensitive to exactly what tech debt describes: inconsistent schemas, undocumented side effects, and workflows that only exist in one person's head.

Your context will differ from this one. Thirty minutes is enough to say by how much.

Talk it through
read this before you cite it

What this engagement does not claim

The same caveats the case studies hub carries, narrowed to this engagement so nothing here is a surprise to your analyst.

  1. 01

    Not an AI engagement.

    Scrum Master support for two squads and agile coaching across the business. No models, no agents.

  2. 02

    The recovery of trust is qualitative.

    Delivery predictability was measured. The recovery of confidence in the technical department is reported as it was described to us at the time, not as a metric.

If you want to know whether we have done your version of this, ask on the call and we will answer plainly.

Talk it through
the other call

See how we did it

A real engagement walked through by the person who led it, then the same method applied to yours.

  • The ways of working, published in full and free to adopt without hiring us.
  • The target operating model James co-led at HSBC: designed and piloted for 500 teams, with global rollout due in 2026 and not yet rolled out.
  • The AI build inside a live London specialty insurer: a working proof of concept, month by month, with the client anonymised to a market.

Everything the call covers about our work is already published on this site. What it adds is the person who did that work, and your own situation put through the same method.

The 30-minute discovery call starts with your problem. This one starts with our work.

Pick a time on cal.com
book a call

Want the same thing, in your organisation?

A 30-minute call with James Rooney. We will tell you which parts of this we have done before and which we would be doing for the first time, and you will leave with a rough scope either way.

most start with a fixed-price AI Readiness Audit · £44,000 · 4 weeks · working prototypes

// pick a slot · cal.com/tenhaw/professional-servicesLIVE CALENDAR

Calendar not loading? Open it on cal.com or email hello@tenhaw.com.

Questions about this engagement

What did Tenhaw actually deliver at Greggs?

Scrum Master support for two squads, Mobile App and Integration, plus agile coaching across the wider business, over six months. Greggs had launched a mobile app so customers could order and earn rewards, but the rushed setup of technical ways of working created friction with Marketing and other departments. We refined Story Points so tracking followed real capacity. Product was coached to prioritise from data, and the workshops and alignment sessions we ran taught non-technical teams how agile actually works. By the end delivery was predictable and prioritisation conversations were realistic, and confidence in the technical department had recovered.

What has coaching a delivery team got to do with agentic change?

More than it looks. This was Scrum Master support for two squads and agile coaching across the wider business, and the preconditions it built are the ones agentic change depends on. Agents amplify whatever operating culture they land in, so cross-functional trust and a shared, data-backed language for value have to be sound before automation arrives. Six months bought Greggs predictable delivery. It also bought prioritisation conversations that were realistic and focused, and a technical department the rest of the business trusted again.

Did Tenhaw exist when the Greggs work was delivered?

Some of the work on this site predates the company, and we are straightforward about which. Greggs sits in the group of engagements delivered under the Tenhaw banner, alongside Anglo American, Yondr, Colart, Tecknuovo and Globelynx. Several in that group predate incorporation and were delivered by James Rooney personally on contract, and we will walk you through which is which on a call. The distinction matters more for the paperwork than for the work. Tenhaw is founder-led, James leads every engagement personally, and the six months of Scrum Master support and coaching described in this study happened as written, whichever banner it sat under.

How do you rebuild trust between a technical team and the rest of the business?

By making delivery predictable enough that commitments mean something again. At Greggs the problem was never technical. An app team had been stood up at speed during the pandemic, ways of working were invented on the way, and the friction with Marketing and other departments had eroded confidence in the whole technical department. We rebuilt the numbers first, refining Story Points so tracking reflected real capacity, then ran alignment sessions and prioritisation workshops that put those numbers in front of the other departments. Trust followed the data. Once delivery became predictable, prioritisation conversations turned realistic and focused, and confidence in the technical department recovered.

How do you prove paying down tech debt speeds up delivery?

Use the delivery data. The claim that paying down tech debt speeds up delivery is usually made as a technical argument and lost as a budget conversation, because nobody outside engineering can weigh an engineer's opinion. At Greggs we used delivery data to prove the payback of addressing tech debt, and the numbers are what let the argument survive contact with Marketing and the other departments. The data showing tech debt work accelerated timelines strengthened collaboration across the departments. The wider lesson is that a shared, data-backed language for value turns the hardest prioritisation arguments into something every department can judge on the same terms.

Why do rushed app launches cause delivery problems later?

Because ways of working invented under pressure harden into the operating model. Greggs stood its app team up at speed so customers could order and earn rewards, and the rushed setup created friction with Marketing and other departments. The pattern recurs, and it is not a technical one. A team ships under pressure, estimates stop being believed, then prioritisation turns into a negotiation about credibility rather than value. At Greggs it took a six-month engagement of capacity-based tracking and coaching that reached beyond engineering to make delivery predictable and the department trusted again.

Does agile coaching work outside engineering teams?

Yes, and at Greggs coaching beyond engineering was a stated part of the brief, not a side effect. Alongside Scrum Master support for the Mobile App and Integration squads, we ran prioritisation workshops and alignment sessions that showed non-technical teams how agile actually works. The point was never to make Marketing run stand-ups; it was to give every department a shared, realistic picture of capacity, so conversations about what gets built next start from data rather than assertion. That organisation-wide coaching is a large part of why predictable delivery turned into recovered trust across departments.

Why does team credibility matter before starting an AI programme?

Because a department whose commitments are not believed cannot sequence anything, including an AI programme. A head of AI inheriting a distrusted technical department will find the blocker is not the model. It is that no estimate the department makes is taken seriously, so nothing can be planned against. The Greggs engagement is what fixing that looks like. Six months of Scrum Master support and coaching made delivery predictable and made the department's numbers believable again. An AI programme gets planned against those numbers like everything else, so they have to be believable before the technology arrives.

What would a Greggs-style engagement cost from Tenhaw today?

It would be sold as Programme and Delivery Management at £18k–£35k per month, depending on scope. The Greggs work, Scrum Master support across two squads plus agile coaching beyond engineering, sits squarely in that service. What you are buying is senior delivery leadership that makes output predictable and gives the business numbers it can plan against. Tenhaw engagements are retainer-shaped with an exit date agreed at kickoff and 30 days' notice either side, and a month that delivers no measurable value is reported as a failed month. A 30-minute call is the quickest way to size your version of it.

How do you get prioritisation decisions based on value rather than politics?

Give every side the same numbers and coach them to argue from them. At Greggs, friction between the technical department and Marketing meant prioritisation ran on assertion. Refining Story Points for capacity-based tracking rebuilt the numbers, Product was coached to prioritise from data, and the prioritisation workshops and alignment sessions put that evidence in front of every department at once. That is the shift the study records. Prioritisation conversations became realistic and focused, and even the hardest sell, spending delivery time on tech debt, was won with delivery data rather than opinion. Shared numbers that everyone believes leave politics very little to work with.

Does retail tech debt have to be paid down before AI modernisation?

Not all of it, and the real decision is which parts. Pay down the retail tech debt that sits directly in the path of the work you intend to automate, and keep the rest costed and visible. Tech debt and an AI modernisation programme draw on the same delivery capacity, so it gets settled as a budget question and not an engineering one. At Greggs we used delivery data to show that tackling tech debt accelerated timelines, which gave Marketing and the other departments a shared basis for agreeing the order of work. That same data lets you sequence modernisation around the debt that actually blocks it. Clearing the lot first is rarely the cheapest route.

Is our delivery problem the team or the way they work?

Usually it is the way they work. Greggs shows the difference clearly. The app team was stood up at speed so customers could order and earn rewards, and it was the rushed setup of technical ways of working, not the engineering, that created friction with Marketing and other departments. The tell is where the disbelief sits. One team missing its own dates is a team problem. Several departments no longer believing any estimate is an operating model problem, and more pressure on the team will not shift it. What made delivery predictable again was six months of Scrum Master support and capacity-based tracking, with coaching that reached beyond engineering.

Should Marketing be in the prioritisation workshop, or just Product?

Both, and at Greggs that was rather the point. Product was coached to prioritise from data, but the friction sat between the technical department and Marketing, so a workshop with only Product in it would have moved the argument rather than settled it. We ran prioritisation workshops and alignment sessions together, the sessions teaching non-technical teams how agile actually works so everyone in the room could read the capacity numbers. Once the people asking for work and the people doing it were looking at the same figures, prioritisation became a choice between options instead of a test of anyone's credibility.

What happens if the delivery data makes the team look bad?

It often does at first. What you do with that first honest picture decides the engagement. Capacity-based tracking replaces optimistic estimates with what the team has actually demonstrated, so the early numbers tend to be smaller than what the business believed it had been promised. At Greggs the refined Story Points went straight into prioritisation workshops with Marketing and the other departments. They were the basis for deciding what came next, not a scorecard for what had gone before, and confidence in the technical department recovered. Used as a stick, the same data destroys the trust it was gathered to rebuild.

How do you tell whether agile coaching actually worked?

By what changes outside the team, not by how the ceremonies feel. Ask whether what the team forecasts matches what lands. Ask whether other departments plan against those numbers, and whether the arguments have moved from credibility to value. Greggs is what passing looks like. After six months of refined Story Points and capacity-based tracking, delivery was predictable and prioritisation conversations were realistic and focused, and confidence in the technical department had recovered. We hold our own engagements to the same standard. They are retainer-shaped, and a month that delivers no measurable value is reported as a failed month.