Lago vs Kill Bill

Cost is driven by the people and services around the software, not the license fee, since both projects are free to download. Lago is licensed under AGPLv3 and Kill Bill under Apache License 2.0, so neither charges a license fee for the core. The recurring costs are the infrastructure you run, the engineers who maintain it, and any paid payment gateway or support contract you choose. For Lago, the stack is a front end, an API, workers, PostgreSQL, Redis and Gotenberg, plus optional ClickHouse for high event volumes. For Kill Bill, the stack is a Java WAR in Tomcat, a supported database such as MySQL, plugins and the Kaui back office. Ask any quote to separate one-time setup from recurring operations, and to name who pays for each piece.

Yes, if your team has the skills to operate the components and the time to keep them patched. Both are open source, so you can deploy them yourself without buying a license. Lago's self-hosting docs recommend pinning the last tagged version rather than the latest image tag, and point larger deployments to Helm charts and dedicated workers, which means someone must own upgrades and capacity. Kill Bill's getting started guide requires JDK 11 for the Tomcat installation, and its core team tests against MySQL, MariaDB 10 and PostgreSQL 12, so your database and Java operations need an owner. Be realistic about the gap: Kill Bill includes no support or SLA by default, so an internal team carries the full burden of incident response. Decide who holds that responsibility before you choose.

Engineering owns the deployment, integrations and data flow, while finance owns the rules that determine what is charged. On the engineering side, expect work on the payment gateway connection, since Lago needs a separate processor such as Stripe, Adyen or GoCardless, and Kill Bill connects to gateways such as Stripe, Braintree and PayPal through plugins. Expect integration work for accounting and CRM systems, which Lago lists as NetSuite, Xero, Salesforce and HubSpot. On the finance side, pricing models, tax treatment, invoice formats, credit rules and dunning policy need written decisions before build starts. Kill Bill's Kaui back office gives internal teams role-based access for support, product configuration and finance reporting, which can shift some of that work to finance staff. Ask any partner to name these responsibilities in the written scope.

Plan in phases tied to decisions, not to a fixed number of weeks. The duration depends on how many products and pricing models you need, how many gateways and accounting systems must connect, how much historical data must migrate, and how many approvals sit inside finance and tax. Lago's model of metering events, applying pricing and producing invoices means usage data quality often sets the pace, so validate event pipelines early. Kill Bill's subscription model, with upgrades, downgrades, invoices and credits, often takes longer to define in the product catalog than to deploy. No researched figure is available for either project, so ask each vendor or partner for a phased plan with milestones and the assumptions behind each one, and check that the timeline lists its dependencies on your own environment.

Kill Bill ships without support or an SLA, so vendor-backed response times, guaranteed fixes and contractual uptime are not part of the default package. The project is open source under Apache License 2.0 and has been in production since 2010, but the README states that no support or SLA is included. The Billing Project, LLC owns the codebase and trademarks, which is useful for licensing clarity but does not replace an operational support contract. Plugins for gateways, tax and fraud are also deployed as JARs in your environment, so compatibility after upgrades becomes your responsibility unless a contract covers it. Ask any provider what they will monitor, how they handle incidents, and which parts of the plugin estate they will maintain.

A managed or paid option is worth comparing when your team cannot staff the operational load or when a feature you need sits behind a paid tier. Lago offers a forever-free open-source edition with fundamental billing features, and Enterprise plans that add premium features, so check whether dunning, tax or accounting integrations you need are in the free scope. Lago also documents Lago Cloud as a managed option, which removes the need to run workers, PostgreSQL and Redis yourself. For Kill Bill, a paid support or hosting arrangement from a provider would fill the support gap described above. Compare the managed cost against the internal hours, on-call duties and upgrade risk it removes, using the same written scope for each option.

Legal should review how each license applies to your deployment and to any changes you make. Lago's platform is licensed under AGPLv3, which carries source disclosure obligations for network-accessed modifications, while its agent SDKs and MCP server are MIT licensed in separate repositories. Kill Bill is licensed under Apache License 2.0, which is permissive and does not carry the same network disclosure duty. Confirm with counsel how the AGPL-3.0 terms interact with your planned customizations and internal-only use. Do not treat this summary as legal advice; confirm the terms with your legal team before you build on either platform.

Check that the written scope lists systems, deliverables, acceptance criteria and exclusions before any work starts. DeployOpen plans, implements, customizes, integrates, hardens, backs up, upgrades and documents self-hosted open-source platforms inside your own infrastructure, and most engagements are fixed-scope with scope, deliverables and timelines agreed in writing. DeployOpen does not publish a price list, so a quote follows from that written scope. Ask for the gateway and accounting integrations named one by one, the data migration approach, the test and cutover plan, and who owns runbooks after handover. Ongoing support, upgrades and testing are available as retainers, which should be priced separately from the build.