This document discusses British Gas's transition from a monolith architecture to microservices. It outlines their criteria for the new stack, including fast time to market, independent lifecycles, simplified deployment, and granular scalability. It also discusses some of the technologies they considered like Spring Boot, Netflix OSS, Docker, Kubernetes, and Nomad. Finally, it provides lessons learned around planning for infrastructure changes, having a solid CI/CD pipeline, redefining testing approaches, implementing powerful monitoring, and engaging business teams.

1. Monolith to Micro-services
Here be dragons…
Andy Czerwinski
Digital Architect – British Gas
Twitter: @czeggers

2. Our past . . .

3. Seeking the truth . . .

4. Our criteria for new stack . . .
• Fast time to market
• Independent lifecycle - business features
• Support multiple versions
• Simplified deployment
• Granular scalability and improved availability

5. Enlightenment . . .
Spring boot & Netflix OSS components
+
Docker
+
Kubernetes

6. Reality. . .
Spring boot & Netflix OSS components
+
Process isolation
+
Nomad

7. Our transition approach . . .
• Get comfortable with working in a distributed environment
• Identify integration patterns with existing stack
• Scope a micro-service based on bounded context
• Invest in powerful monitoring tools
• Ensure availability of micro-services
• Get the right engineers on the job

8. Our baby steps. . . (present)

9. Our goal… And where we are…

10. Lessons learnt . . .
• Plan for infrastructure changes (it is inevitable)
• Solid CI / CD pipeline is a must (engage the teams early)
• Existing approach for testing should be re-defined
• Plan out for powerful monitoring tools
• Business teams need to be engaged with clear road-map

11. Finally . . .
Thank you!
And a big thank you to our Engineers
Email: andy.czerwinski@centrica.com
Twitter: @czeggers