---
title: "MGS1104: this program does not link the Buzz engine"
description: Fires when a Go program built on the magus library opens a workspace that has a magusfile without linking the Buzz engine, so the load fails instead of returning a workspace with no magusfile targets.
tags: [MGS1104, capability, sdk, library, buzz, engine, magusfile, embed]
---

# MGS1104: this program does not link the Buzz engine

A Go program asked the magus library to evaluate a magusfile, and the program
was built without the Buzz engine that evaluates one. The load stops there.

```text
[MGS1104] cannot evaluate /repo/magusfile.buzz: this program does not link the
Buzz engine; add the blank import _ "github.com/egladman/magus/buzzengine" to
its main package
```

The `magus` command links the engine, so this only reaches a program that
imports `github.com/egladman/magus` as a library.

## Why

The library does not link the engine on its own, so a program that never
evaluates a magusfile does not carry the Buzz VM.

The alternative to failing is **silence**. A workspace loaded without its
magusfiles has no custom targets, no `magus.project()` settings and no
per-target policy, and it renders exactly like a workspace that declares none.
Only one of those is true, and nothing in the result says which.

So the load returns `*types.EngineNotLinkedError` instead of a partial
workspace. A workspace with no magusfile still opens without the engine.

## Fix

Link the engine from the program's main package:

```go
import _ "github.com/egladman/magus/buzzengine"
```

Match the error from Go with `errors.As`:

```go
var notLinked *types.EngineNotLinkedError
if errors.As(err, &notLinked) {
    // the program was built without buzzengine
}
```

## See also

- [Go SDK](../../go-sdk.md): what the library does and does not link.
- [MGS1101](MGS1101.md): a capability reported as unavailable, never as empty.