$ npm install connect-dynamodb

var options = {
    // Optional DynamoDB table name, defaults to 'sessions'
    table: 'myapp-sessions',

    // Optional path to AWS credentials and configuration file
    // AWSConfigPath: './path/to/credentials.json',

    // Optional JSON object of AWS credentials and configuration
    AWSConfigJSON: {
        accessKeyId: <YOUR_ACCESS_KEY_ID>,
        secretAccessKey: <YOUR_SECRET_ACCESS_KEY>,
        region: 'us-east-1'
    },

    // Optional client for alternate endpoint, such as DynamoDB Local
    client: new AWS.DynamoDB({ endpoint: new AWS.Endpoint('http://localhost:8000')}),

    // Optional clean up interval, defaults to 600000 (10 minutes)
    reapInterval: 86400000    // 1 day
};

var connect = require('connect');
var DynamoDBStore = require('connect-dynamodb')(connect);
connect()
    .use(connect.cookieParser())
    .use(connect.session({ store: new DynamoDBStore(options), secret: 'keyboard cat'}));

var DynamoDBStore = require('connect-dynamodb')(express);
var app = express(
    express.cookieParser(),
    express.session({ store: new DynamoDBStore(options), secret: 'keyboard cat'});
);

var app = express();
var session = require('express-session');
var DynamoDBStore = require('connect-dynamodb')({session: session});
app.use(session({store: new DynamoDBStore(options), secret: 'keyboard cat'}));