Games like Gutfarm
Games like Gutfarm include Forager, Oxygen Not Included, Factorio, Until We Die, and Mindustry. We matched them by the tags players give Gutfarm on Steam (Action, Tower Defense, Farming Sim, Survival, and Strategy): closest matches first, and among equally close ones the better-known games.

Forager
Shared: Survival · Farming Sim · Pixel Graphics

Oxygen Not Included
Shared: Survival · Base Building · Resource Management

Factorio
Shared: Base Building · Strategy · Resource Management

Until We Die
Shared: Survival · Strategy · Tower Defense

Mindustry
Shared: Tower Defense · Base Building · Strategy

They Are Billions
Shared: Base Building · Strategy · Survival

Stardew Valley
Shared: Farming Sim · Pixel Graphics · Agriculture

Rise to Ruins
Shared: Tower Defense · Survival · Strategy

Sheltered
Shared: Survival · Base Building · Strategy

Terraria
Shared: Survival · Pixel Graphics · 2D

Frostpunk
Shared: Survival · Strategy · Resource Management

The Riftbreaker
Shared: Tower Defense · Base Building · Survival

The Escapists
Shared: Strategy · Pixel Graphics · Action

Kingdom Two Crowns
Shared: Tower Defense · Base Building · Strategy

Thronefall
Shared: Tower Defense · Strategy · Action

Plants vs. Zombies GOTY Edition
Shared: Tower Defense · Strategy · 2D

Kingdom Rush Origins - Tower Defense
Shared: Tower Defense · Strategy · 2D

Kingdom Rush - Tower Defense
Shared: Tower Defense · Strategy · Action

Cluckmech Oasis
Shared: Tower Defense · Strategy · Action

ARK: Survival Ascended
Shared: Survival · Base Building · Action

Bee Island
Shared: Tower Defense · Strategy · Action

Dig or Die
Shared: Survival · Tower Defense · Action

Once Human
Shared: Action · Survival · Building

RimWorld
Shared: Survival · Base Building · Strategy