Prevent Minecraft Villager from changing jobs?

Is there a way that the Villager will only do the job I assigned to it via Command?

So despite barrels, he shouldn't switch to Fischer.

Turning the AI off would do that, but would also like the Villager to be able to move within a certain radius.

Is there a solution to this?

You have to lock him up for good or bad, or you can just pack his object so that it stays as it should

No other possibilities? Have barrels as decoration, which is then impractical 😀