Short answer
Jack is the foreman whose Town Workshop unlocks factory technology. His line runs Jack in a Boat, Workshop Hours, the workshop repair (5 Building Kit I and 5 Wooden Kit I), Man of Steel (3 Steel Ingots) and Factory Tour, each worth about 10 reputation. At 60 reputation he signs Gunter's PR contract; at 80 he gives his Pride fragment.

The Town harbour at dusk
View full-size image ↗Official promotional screenshot · © Lazy Bear Games / tinyBuild · Official media kit · Material credits
Who Jack is
Jack is a foreman and builder with a shipbuilding background.
You first meet him on Twins' Land during Jack in a Boat; after that he works from Jack's Workshop in The Town.
His reputation is the gate for several factory and steel technologies, so it pays to advance him early.
Jack in a Boat
The first quest asks for 5 Wooden Planks and then 5 Bronze Details.
You also need 10 Village reputation to persuade the brothers to help with the rowing.
Workshop Hours and the repair
Complete the Workshop Hours order at the Town Warehouse and speak to Jack; it gives 10 Jack reputation and one Town Gratitude.
Clear the zombies around his workshop during Jack's Back in Business. Entering the liberated workshop gives another 10 reputation and 2 Town Gratitude.
Then bring 5 Building Kit I and 5 Wooden Kit I, as two separate hand-ins in either order. The repair gives 10 reputation, 2 Town Gratitude and makes you Jack's apprentice.
Delivering only one kit type leaves the workshop unfinished — a common reason the quest seems stuck.

The Town workshop in the official media kit, the kind of space Jack's line restores. Not a quest screen.
View full-size image ↗Official promotional screenshot · © Lazy Bear Games / tinyBuild · Official media kit · Material credits
Man of Steel and Factory Tour
Man of Steel sends you to the Bishop at the Royal Foundry for high-quality steel. Hand Jack 3 Steel Ingots for 10 reputation and 3 Town Gratitude.
It unlocks Factory Tour, which awards another 10 Jack reputation.
Our steel guide covers the route to the Royal Foundry.
The reputation gates
60 reputation: required for Stars, Lies, and Contracts, where Gunter recruits Jack as a frontman and Jack signs the PR contract.
70 reputation: needed alongside Iron Products to research Steel Smithing and its Steel Anvil.
80 reputation: unlocks Jack's Pride fragment, a portal fragment reward.
Fextralife also notes a 50-reputation step and his restoration requests before the Conveyors technology opens.
If you are stuck below a gate
Count what you have done: Workshop Hours, entering the workshop, the repair, Man of Steel and Factory Tour are 10 each.
If you are short, look for the step you skipped — usually the second kit hand-in or the steel delivery.
Sources
- communityFextralife — Jack
- communityFextralife — Jack Workshop Repair
- communitywikily.gg — Man of Steel
- communitywikily.gg — Steel Smithing
- communityNeoseeker — Jack Quests Walkthrough