The Hays zero-disruption playbook: how to deliver a smooth cloud migration
Client Profile
Customer Name: Hays
Established: 1968
Customer Since: January 2024
Employees: 10,000+
Sector: Recruitment
Watch: Hays cloud migration case study | How to achieve zero disruption
When the news arrived, it was not the result of a long planning cycle or a strategic shift that had been months in the making. It was a blunt, non–negotiable reality handed down without warning. The hosting provider supporting a major part of Hays’ environment was exiting the hosting business, which meant the data centres that housed critical systems were due to close within a fixed window. There was no negotiation, no extension and no safety net.
As Simon Gerhardt, IT Operations Director at Hays, a multinational company providing recruitment and human resources services, put it during a conversation about the programme, it was a moment that felt “completely out of the blue” and one that carried very real consequences. The business relied on the systems inside those data centres to operate globally, and any disruption would have been immediately visible to customers, consultants and candidates. The stakes could not have been higher.
For many enterprise technology leaders, this scenario feels uncomfortably familiar. Most organisations do not wake up one day deciding they want to run a large-scale cloud migration. They are pushed into it by a deadline they did not set or by an external pressure they cannot control. The question is never whether the work needs to be done, but how to deliver it without breaking the business in the process.
What follows is the story of how Hays navigated that challenge, and the lessons that other CIOs and CTOs can take from the experience.
The honest first reaction
When Simon was asked how he felt in the moment he learned about the closure, the answer was refreshingly honest. He described his first reaction as “terror”. It was not the technology that sparked that feeling but the reality of the task in front of him. The team now had to move an entire global estate into a new environment, meet an immovable deadline and do so in a way that the business would not feel.
This is something many leaders recognise. It is not the cloud migration itself that creates anxiety. It is the collision of complexity, time pressure and the expectation of absolute continuity. When nothing in the business is allowed to slow down, the margin for error becomes incredibly thin. What Hays did next is what set this programme apart.
The value of pausing before acting
Under heavy time pressure, the natural instinct in most organisations is to start building immediately. Teams spin up environments, draft timelines and begin cutting over early workloads in order to show progress. It creates the appearance of momentum, but it often masks a deeper issue: speed without clarity nearly always leads to delays, rework and risk later on.
Hays took a different approach. The team deliberately paused and used the early phase of the programme to create a complete and honest understanding of the estate. This meant mapping every connection, every dependency, every hidden service and every system of record. It also meant defining the architectural principles that would guide all subsequent decisions.
This period laid the foundations for everything that followed. It created a shared understanding of what could be modernised immediately, what needed to move first, what required a more careful sequence and what guardrails could not be compromised under any circumstances.
As Simon said, they reminded each other regularly that you should “measure twice and cut once”. That mindset provided a sense of control at a time when the situation itself felt anything but controlled.
A chance to remove the weight of the past
Deadlines compress decision making. They remove bureaucracy and force teams to focus on what actually matters. In Hays’ case, it created a rare opportunity to leave behind more than a decade of accumulated technical debt, duplicated services and technology choices that made sense once but were now costing efficiency.
By moving with discipline and structure, the team managed to simplify the estate, adopt a cloud only direction and shift several services into environments where they would be easier to maintain, scale and secure. They did not attempt a wholesale transformation of every application in the estate. Instead, they brought sensible modernisation forward wherever it would create immediate and lasting benefit.
This combination of necessity and clarity is what turned a high-risk migration into a strategic advantage.
The pattern-based automation approach that made scale possible
By the time the first workloads were ready for migration, something important had happened. The team had shifted away from treating every migration as a standalone effort and had instead created a library of repeatable patterns. These patterns defined how a category of workload should be assessed, built, secured, tested and cut over. This pattern-based approach allowed for automation, minimising manual tasks and increasing the cadence and accuracy of every migration and cutover.
Once those patterns had been validated in dev and test environments, they were used across hundreds of workloads. As Simon described it, “if it works in test on that server, we can roll it out across these 400”. That level of consistency made delivery faster and it also reduced risk because the team knew that each workload was following the same proven approach.
The effect of this was significant. Confidence increased with every successful wave. The challenges that looked large in the early weeks became more manageable as the programme moved forward. Progress accelerated not because the team worked harder, but because the process became cleaner and more predictable.
The moment that defined the programme
Despite the progress, there was a moment where the entire programme could have taken a different turn. During one of the late evening cutovers, the team identified a technical issue that was not catastrophic but was unusual enough to create concern. They were already in the change window. Everyone was present. The natural instinct in many organisations would be to push through and deal with the consequences later.
Instead, the engineer leading the cutover made a call that changed everything. They simply said, “we are not going to go live tonight”. It was a moment of clarity, judgment and maturity.
Over the next three days, the team diagnosed the issue properly, resolved it and completed the migration without any impact to the business. There was no downtime, no noisy incident afterwards and no lingering problems waiting to appear weeks later. It was a demonstration of why empowered engineers, psychological safety and disciplined patterns matter as much as technology.
Resilience that works in the real world
One of the most transformative outcomes of the migration was the improvement in operational resilience. Before the move, disaster recovery testing required significant planning and often relied on extended weekend windows. After the migration, the estate was modernised to the point where component level DR testing could be performed during normal working hours. As Simon said, with clear relief, “we have our Easters back”.
This shift captures the true value of cloud. It is not the location of resources that creates advantage but the ability to automate, scale, simplify and test without causing disruption. The estate became easier to manage and the teams became more confident in their ability to respond to issues quickly.
The path to predictive operations
Hays now has a foundation that allows them to adopt AI-based operational improvements in a meaningful way. Rather than talking about AI abstractly, Simon described it as an intelligent assistant that can help teams spot patterns, identify anomalies, prevent capacity issues and strengthen the security posture of the estate.
This is only possible because the environment is now sufficiently standardised, observable and well governed. In other words, the modernisation created the conditions for future innovation rather than trying to force innovation onto an unstable base.
Clarity before speed
Disciplined discovery
Repeatable patterns
Empowered experts
Consistent decision making
Trust and psychological safety
The courage to pause when something feels wrong
Hays met a deadline they did not choose, avoided disruption in a global business and emerged with a modern platform that will support them for years to come. For any CIO or CTO facing similar pressure, their story is a reminder that the path to cloud success is not defined by the technology itself, but by the quality of leadership, engineering culture and decision making that surrounds it.
