Antonym of "Jobsworth"

Question

Word for someone who isn't jobsworth. Someone who, once he'd been given a job, is looking to get that job done the best way possible for everyone (not just himself).

I tried "proactive" but it doesn't fit:

"The ideal candidate would be a non-jobsworth teacher, who is looking to really teach people, not just clock in and spew the material"

Proactive is more about dynamics; someone who takes initiative and reaches out.
In this case, the dynamics is passive, the teacher doesn't normally reach out or take initiative.
For example: my teachers were great. They thought about how to deliver the material with us in mind. But they wouldn't reach out to us or proactively seek to find students who were trailing behind.

Answer 1

Unless British English leans more on the mental health definition, I'd say "committed" foots the bill. "Passionate" or "student-focused" would be other options.

Answer 2

I like go-getter as an antonym, as it seems to be in the same register as jobsworth--which I've never heard in AmE. go-getter may not be common in Great Britain, though. Google

go-get·ter ˈɡō ˈˌɡedər/ noun informal noun: go-getter; plural noun: go-getters

an aggressively enterprising person.

synonyms: achiever, high flyer, success story, high achiever, man/woman of action; bigwig, mover and shaker, dealmaker, wheeler-dealer, hustler

"he wasn't enough of a go-getter to make it as a salesman"

Answer 3

Have a look at Belbin team roles, perhaps a Completer Finisher.

The Completer Finisher is a perfectionist and will often go the extra mile to make sure everything is "just right," and the things he or she delivers can be trusted to have been double-checked and then checked again. The Completer Finisher has a strong inward sense of the need for accuracy, and sets his or her own high standards rather than working on the encouragement of others. They may frustrate their teammates by worrying excessively about minor details and by refusing to delegate tasks that they do not trust anyone else to perform. - https://en.wikipedia.org/wiki/Team_Role_Inventories#Completer_Finisher

Also see http://www.teamopoly.com/cf.htm