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SMS verification with retry logic and voice fallback

Created by: Twilio

Verify
JavaScript
Quick Deploy

Adding a retry buffer to your phone verification or authentication workflow can prevent:

Accidentally spamming a user with repeated text messages
Hitting API rate limits
SMS pumping or unnecessary spend

This project includes several user interface and user experience best practices for a verification workflow, incorporating the Twilio Verify API and the Twilio Lookup API. Learn more in the blog post: Best practices for managing retry logic with SMS 2FA.

If you prefer to test the Verify API channels for one-time passcodes (SMS, voice, and email), including message translations, you can check out the One-Time Passcode Verification (OTP) code exchange project.

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Install Node.js
The Node.js runtime is required to run the Twilio CLI and the sample code.
Download and install Node.js
Install Twilio CLI
The Twilio CLI is a command line tool that allows you to interact with Twilio APIs and services, and is necessary to deploy this template.
The suggested way to install the Twilio CLI on macOS is to use Homebrew. If you don't already have it installed, visit the Homebrew site for installation instructions and then return here.
Once you have installed Homebrew, run the following command to install the Twilio CLI:
brew tap twilio/brew && brew install twilio
Not using macOS? View the docs on all other installation methods.
Install the Serverless Toolkit
Beyond the base commands, Twilio CLI's functionality can be extended through plugins. In this case, the Serverless Toolkit plugin is needed to deploy the serverless functions that will power this template.
twilio plugins:install @twilio-labs/plugin-serverless
Learn more about Twilio CLI plugins
Login to the Twilio CLI
In order for the CLI to access your Twilio account and execute commands on your behalf, you need to log in and provide your Twilio credentials. This can be done by running:
twilio login
You will be prompted for your Account SID and Auth Token, both of which you can find on the dashboard of your Twilio console.
Create and configure a project with this template
To create a new project with the name example and the current template, run the following command:
twilio serverless:init example --template=verify-retry
This will create a new directory called example (or whatever name you picked) and will download all necessary files and dependencies for you.
(information)
Check your template's README
Depending on the template, there might be additional setup instructions necessary to make the project work.
Check the instructions for this template to see if there are any additional steps to complete.
Host on Twilio
You can now deploy your code by running the following command:
cd example twilio serverless:deploy

SMS verification with retry logic and voice fallback

Check your template's README