The Twelve-Factor App methodology is twelve best practices for building modern, cloud-native applications, with guidance on things like configuration, deployment, runtime and multiple service communication. It applies to a diverse number of use cases, from web applications and APIs to data processing applications. Although serverless computing and AWS Lambda have changed how application development is done, the Twelve-Factor best practices remain relevant and applicable in a serverless world. You'll learn how to directly apply the Twelve-Factor methodology to serverless application development with Lambda and Amazon API Gateway. As you’ll see, many of these factors are not only directly applicable to serverless applications, but in fact a default mechanism or capability of the AWS serverless platform. 

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Applying the Twelve-Factor App
Methodology to Serverless
Applications
Rory Jacob
Software Engineer
AWS Lambda
S R V 2 1 8
James Hood
Sr. Software Engineer
AWS Serverless Applications

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About Us

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Agenda
What is the Twelve-Factor App Methodology?
How does this apply to Serverless Applications?
Q&A

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Twelve-Factor App Methodology
• Developed by developers at Heroku and first presented in
2011 by Adam Wiggins
• Best practices for building modern, cloud-native
applications
• Declarative
• Clean Contract
• Deployments
• Minimize divergence in environments
• Scale up

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Twelve-Factor App Methodology
• Broken down into twelve separate categories
1. Codebase
2. Dependencies
3. Config
4. Backing services
5. Build, release, run
6. Processes
7. Port Binding
8. Concurrency
9. Disposability
10. Dev/prod parity
11. Logs
12. Admin processes

8. © 2018, Amazon Web Services, Inc. or its affiliates. All rights reserved.
Twelve-Factor App Methodology
• Broken down into twelve separate categories
1. Codebase
2. Dependencies
3. Config
4. Backing services
5. Build, release, run
6. Processes
7. Port Binding
8. Concurrency
9. Disposability
10. Dev/prod parity
11. Logs
12. Admin processes

9. © 2018, Amazon Web Services, Inc. or its affiliates. All rights reserved.
Twelve-Factor App Methodology
• Broken down into twelve separate categories
1. Codebase
2. Dependencies
3. Config
4. Backing services
5. Build, release, run
6. Processes
7. Port Binding
8. Concurrency
9. Disposability
10. Dev/prod parity
11. Logs
12. Admin processes

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12. “Store config in the environment”
The Twelve Factor App

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3. Config
const tableName = “beta-table”
const endpoint = “beta.endpoint.com”
func Handler(request string) (string, error) {
// do some work
}
func main() { lambda.Start(Handler) }

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3. Config

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3. Config
Env Vars:
Endpoint: beta.endpoint.com
beta-table

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3. Config
Env Vars:
Endpoint: beta.endpoint.com
beta-table

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3. Config
Env Vars:
Endpoint: beta.endpoint.com
beta-table
Env Vars:
Endpoint: prod.endpoint.com
prod-table

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3. Config
var tableName string
func init() {
tableName = os.Getenv(“TableName”)
}
func Handler(request string) (string, error) {
// do some work
}
func main() { lambda.Start(Handler) }

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20. “Treat backing services as attached
resources”
The Twelve Factor App

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4. Backing Services

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23. “Scale out via the process model”
The Twelve Factor App

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8. Concurrency

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8. Concurrency

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8. Concurrency

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8. Concurrency

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8. Concurrency

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8. Concurrency

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8. Concurrency

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Twelve-Factor App Methodology
1. Codebase
2. Dependencies
3. Config
4. Backing services
5. Build, release, run
6. Processes
7. Port Binding
8. Concurrency
9. Disposability
10. Dev/prod parity
11. Logs
12. Admin processes

33. Thank you!
© 2018, Amazon Web Services, Inc. or its affiliates. All rights reserved.
James Hood
jahood@amazon.com
Rory Jacob
roryj@amazon.com

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