While amaysim is running some legacy applications in EC2 instances, it is close to living up to its "serverless first" policy and makes extensive use of AWS Step Functions. Most of the old applications have been turned into services or functions. Those functions can be combined in various ways as required.
"The cost of being wrong is a lot lower" when you can quickly fix any mistakes, said James.
AWS provides good training, he said, for example on modernising applications as a way of enabling more rapid releases.
Asked about lock-in resulting from the use of AWS-specific technologies, James said he was aware of the issue, but at this stage amaysim does not want to use multiple clouds, and in any case the change in architecture has freed the company from being financially locked in to large packaged applications for periods of up to ten years.
If the company does decide to migrate again, it is much easier to move individual functions that it is to switch to a different monolithic application, he said.
The changes have unlocked business value, he said, as people have spotted a number of situations where various AWS technologies could be applied to benefit the company.
amaysim makes build or buy decisions very consciously, he said. The strategy is to build the pieces that are specific to the company.
The question is always "where is the business value?," said James. amaysim doesn't sell an undifferentiated product, it sells a customer experience, he explained. So amaysim wants to own its customer funnel and the way customers operate their accounts, but it doesn't want to build its own CRM or billing system.
After amaysim migrated to AWS, it made organisational changes so that the engineers involved in creating a system would still "own" it once it went into production, a practice known as DevOps.
amaysim's IT staff are approximately evenly split between Sydney and Melbourne. Particular functions aren't located in one city or the other, instead teams are spread across the two locations. Teleconferences are used routinely, and people spend time at the other office as required. There's also an iPad-based always-on link between the two premises for casual communication between colleagues.
The adoption of AWS services includes the use of Amazon Connect by the call centre. The company's diverse product suite had led to the creation of multiple contact centres, and change management had become harder than deploying a new system, he said.
The original plan was to use an AWS partner to handle the Amazon Connect deployment, but in the event amaysim merely engaged a partner to confirm that its plan was sound before handling the deployment internally.
One advantage of Amazon Connect is that it allows the contact centre to be "as metricised" as amaysim's web site, he said.
Amazon Connect has been "a big win for us", he said. It was designed to be deployed by IT administrators with no knowledge of AWS, and could have been rolled out in a day if necessary.
Most of the company's agents are now live on the system, and the last ones will be added in January or February 2019.
One of the advantages of Amazon Connect is that the system is usually able to work out who is calling and why, and then take some actions automatically.
The writer attended AWS re:Invent as a guest of AWS, and interviewed Peter James during the event.