RunKit + npm: @aws/dynamodb-expressions

const { AttributePath, ExpressionAttributes, MathematicalExpression, UpdateExpression, } = require("@aws/dynamodb-expressions") const attributes = new ExpressionAttributes; const updateExpression = new UpdateExpression; updateExpression.set('Replies', new MathematicalExpression(new AttributePath('Replies'), '+', 33)); console.log(updateExpression.serialize(attributes)); console.log(attributes.names); console.log(attributes.values); console.log(attributes.values[':val1']);