ServiceM8 15, released in September 2026, lets you build a private add-on for your own ServiceM8 account without a developer account or an add-on store listing. ServiceM8 provides a command line tool called the Addon Kit and a guide to building an add-on with a coding assistant such as Codex or Claude Code, and ServiceM8 hosts the result. The limits are that ServiceM8 support will not troubleshoot what you build, the kit deploys only to the account it is signed into, and nothing checks that your add-on still works after ServiceM8 changes something. For a small tool on your own account, build it yourself. Get a developer when it has to talk to another system, produce a document a customer relies on, or keep working without you watching it.
What a private add-on is
An add-on is a piece of code that runs inside ServiceM8 and shows up as a button, a panel or an action, usually on a job. It can read and write your data through the ServiceM8 API, so it can do things the app does not do on its own: fill a field from another one, generate a document, send a message when a form answer is a particular value, or show a summary the standard screens do not.
Public add-ons are the ones in the ServiceM8 add-on store, built by developers and reviewed by ServiceM8. A private add-on is the same idea, but it is only installed in your account and nobody outside your business sees it. Until ServiceM8 15, building one meant a developer account and a fair amount of setup.
What the Addon Kit does
As I read the developer documentation, the Addon Kit is a command line tool that creates the skeleton of an add-on, lets you develop it locally, and deploys it into the account you are signed into. ServiceM8 hosts the code, so there is no server for you to run. Deployment normally activates the add-on straight away.
Alongside it, ServiceM8 published a guide called "Create a private ServiceM8 Add-on with AI". It is written for someone who is not a developer. You describe what you want in plain English to a coding assistant, it writes the add-on using the kit, and you iterate until it does what you asked. ServiceM8 has been clear that this is the intended path for one off tools on your own account.
The limits
- ServiceM8 support will not troubleshoot it. Their documentation says support is not able to provide how to guidance or troubleshoot issues with the toolkit, and points people to the community instead. When your add-on stops working, the community is where you ask.
- It deploys only to the account it is signed into. There is no built in way to build in one account and install into another. So a partner or developer who builds something for you still has to be inside your account to ship it.
- Nothing watches it. A private add-on that worked on Tuesday can fail on Friday because a field was renamed, an API key expired, or a job came through in a shape the code did not expect. Nobody is told. It simply stops doing the thing, and the office finds out when a customer asks.
- It is only as tested as you tested it. A coding assistant will produce something that works on the example you gave it. Real jobs are messier: a missing photo, a skipped form question, two sites for one customer. Each of those has to be found and handled.
- You are responsible for the keys and the data. The add-on runs with access to your account. Someone has to know what it reads, what it writes, and where any data it sends goes.
When to build it yourself
If the add-on is a small convenience for your own office, does one thing, touches nothing outside ServiceM8, and it would not matter much if it stopped for a day, build it yourself. It is faster and cheaper than paying anyone, and you will learn something about your own data along the way. Plenty of the questions in the ServiceM8 community are exactly this size.
When to get a developer
- It has to talk to Xero, a CRM, a supplier, or any other system. Two APIs, two sets of failure modes.
- It produces something a customer, an insurer or an auditor relies on. A compliance report that is wrong is worse than no report.
- It has to run on a schedule, or run when you are not looking, and someone needs to know if it fails.
- You got most of the way and it stopped. The last twenty percent of an add-on is usually the error handling, and that is the part a coding assistant is least good at without someone who knows what the errors mean.
- More than one person's job depends on it.
What I do with a stalled add-on
Most of the private add-on work I take on starts with something someone already built. I read what you have and what it was meant to do, and tell you in a 15 minute call whether it is an afternoon's fix or a rebuild. Then a fixed quote. I finish it, test it against your real jobs including the odd ones, add logging so failures are visible, and install it in your account using partner access or a staff login you can remove afterwards. You get a one page note saying what it does, what it reads and writes, and what to do if it stops.
After that you keep everything. If you want someone watching it, Care at $252 a month covers monitoring and fixes when ServiceM8 changes something underneath it.
If you are not sure which side of the line your add-on sits on, book the call and I will tell you honestly, including when the answer is to finish it yourself.