TL;DR

In this guide, you will:

  • Use Aviate to configure your billing environment.

  • Switch to Kaui to create your first customer and subscription.

  • Generate and view an invoice.

  • Understand the role of Kill Bill, Aviate, and Kaui.

  • End up with a fully working fictive SaaS company set up for demos.

The example company used throughout this guide is CloudSprout, a fictional SaaS business operating in the UK and France.

Concepts Overview

Before starting, it helps to understand how the pieces fit together.

  • Kill Bill is the billing engine. It manages accounts, subscriptions, invoices, payments, and taxes.

  • Aviate is the Enterprise control and management plane. You use it to configure catalogs, taxes, invoice templates, and tenant settings, as well as proactively monitor the health of the billing engine.

  • Kaui is the billing operations UI. You use it for day-to-day actions such as creating customers, managing subscriptions, and reviewing invoices.

In short:

  • Use Aviate to set things up.

  • Use Kaui to run billing operations.

Step 1: Start in Aviate (Get Started)

When you first log into Aviate, you land on the Get Started screen.

This checklist guides you through the minimum required setup to bill customers.

You should complete all steps in order.

Configure Company Settings

This step defines who you are as a business.

For the purpose of this guide, use the following fictive company:

  • Company name: CloudSprout

  • Business type: B2B SaaS

  • Operating countries:

    • United Kingdom (GBP)

    • France (EUR)

This information is later reused on invoices and customer communications.

The following demo shows how you can configure the company settings via Aviate.

Configure the Catalog

The catalog defines what you sell.

For CloudSprout, create a simple catalog with:

  • A small number of subscription plans (for example Starter, Team, Business).

  • Optional add-ons (for example Extra Storage).

Plan GBP EUR Notes

🌱 Starter

£9 / month

€10 / month

Monthly only

🌿 Team

£29 / month

€32 / month

Monthly or annual

🌳 Business

£79 / month

€89 / month

Annual only
Add-on GBP EUR Billing

Extra Storage

£5

€6

Monthly

Priority Support

£15

€18

Monthly

The following demo shows how you can create the CloudSprout Starter plan via Aviate.

You can similarly create the other plans/products defined above:

cloudsprout plans products

This step only defines products and plans. No customers are created yet.

Refer to Aviate Catalog Guide for additional documentation.

Configure Taxes

Taxes are configured in Aviate and applied automatically by Kill Bill.

For the demo setup:

  • Create a tax code for the UK (VAT) with a 20% rate.

  • Create a tax code for France (VAT) with a 20% rate.

  • Set a valid start date.

Once saved, tax codes can be associated with products.

The following demo explains how you can configure the above tax codes:

Refer to Aviate Tax for additional documentation.

Step 2: Switch to Kaui (Billing Operations)

After completing the Aviate checklist, the next steps happen in Kaui.

From Aviate, use the Billing Operations (Kaui) links to open Kaui in a new tab.

The following demo illustrates how you can switch to Kaui:

Create Your First Customer

In Kaui:

  1. Navigate to Accounts.

  2. Create a new account.

  3. Select the appropriate currency (EUR or GBP).

  4. Save the account.

The following demo illustrates the account creation process in Kaui:

At this point, you have a customer but no billing activity yet.

Create a Subscription

Next, attach a subscription to the customer.

  1. Open the customer account.

  2. Create a new subscription.

  3. Select one of the catalog plans you created in Aviate.

  4. Optionally add an add-on.

  5. Confirm the start date.

Kill Bill immediately generates billing events based on the catalog rules.

The following demo guides you through the subscription creation process in Kaui:

View The Invoice

Once the subscription is active:

  1. Navigate to Invoices in Kaui.

  2. Open the newly generated invoice.

  3. Review:

    • Currency

    • Line items

    • Tax calculation

    • Total amount

This invoice uses the configuration, colors, and the logo defined earlier in Aviate.

The following demo illustrates verifying the generated invoice:

What You Have Achieved

By following this guide, you have:

  • Configured a complete billing environment using Aviate.

  • Created a customer and subscription using Kaui.

  • Generated a real invoice powered by Kill Bill.

  • Understood the separation of concerns between:

    • Kill Bill (engine)

    • Aviate (configuration)

    • Kaui (operations)

You now have a fully working fictive SaaS company ready for demos or experimentation.

Next Steps

From here, you can:

  • Add more products or plans.

  • Experiment with upgrades, downgrades, and add-ons.

  • Explore payments and refunds.

  • Integrate Kill Bill APIs into your own application.

This same flow applies to production environments. Only the data changes.