Using open source tools, developing using Agile and DevOps techniques, and not signing contracts worth over £100 million were three of the core principles of building the NHS Spine 2 system - the digital backbone of the NHS which was migrated on to open source system last year. [See also: 16 CIOs using open source in the enterprise]

Andrew Meyer, the Health and Social Care Information Centre programme head for Spine 2 said that legacy Spine, overseen by Connecting for Health which had been responsible for delivering the National Programme for IT, was incredibly complex but that the new system is already saving the NHS and taxpayer more than £21 million a year on operational costs.

"We wanted no more contracts over £100 million," Meyer told CIO UK at the Gartner Symposium in Barcelona. "Let's get rid of the oligopoly and bring in something more flexible which brings in SMEs as well. We wanted to engage with them because that's where we get the flexibility.

"We also wanted to use open source software, develop using an Agile approach, have a fully resilient service, reduce complexity - and be able to swap out the technology if required.

"We were the biggest Agile development programme within government and all eyes were on us. The availability has been outstanding and we've had some really impressive savings.

The original Spine including the Demographcis Database of 80 million records, Health Information Exchange of 22 million, Summary Care Record of 55 million and the service issuing 1.7 million electronic prescriptions a day, used 28,000 interconnected systems with up to 250,000 concurrent users logged into the site at any one time supporting the Office for National Statistics as well as the NHS and 111 service, Meyer said.

"Spine was big and ugly and hard to change," he explained. "It had taken up to 12 months to make quite a small change.

"It was a brave decision to build NHS Spine in house. Lots of people thought we were bonkers, and they still do - and we had to migrate more than half a billion records.

"We also had to work collaboratively with the incumbent supplier at the end of the 10-year contract." Meyer said that because the infrastructure had been old and costly to maintain, the project had turned into a "bit of a cash cow" for the supplier but that the two parties were able to work together after some adult conversations and work towards a successful migration at the end of the deal's lifecycle.

Meyer said that the migration away from Oracle caused some technological difficulty because the company had built "a special database for the NHS".

"We had to move from our special version of Oracle to upgrade to Oracle 11, then do our own transition," Meyer explained. "We went open source and moved away from SQL to a NoSQL database. It was a brave move but it was the right thing to do - we were able to extrapolate and build a business case around the costs."

Meyer's team called in some support, embedding external developers alongside those from the NHS working as one team, as well as using commercial open source database providers and support through EnterpriseDB, using their PostgreSQL Plus Advanced Server for the security-heavy Postgres database.

"We also use Postgres, which has been very successful in our security environment and supports what the NHS does. We did not totally throw away SQL, but the underlying principle was that our database would use open source.

"Majority of our estate is now open source. Open source can support the enterprise and NHS is a huge enterprise. Not everything is open source, there are fills where we use proprietary and but we could fill in those gaps.

"And now we have it in place, we are always thinking about evolving Spine in other areas."