Games like Little Circuit
Games like Little Circuit include PC Building Simulator, House Flipper, People Playground, Kerbal Space Program, and Stardew Valley. We matched them by the tags players give Little Circuit on Steam (Simulation, Education, Sandbox, Immersive Sim, and Casual): closest matches first, and among equally close ones the better-known games.

PC Building Simulator
Shared: Simulation · Education · Immersive Sim

House Flipper
Shared: Simulation · Sandbox · Casual

People Playground
Shared: Sandbox · Simulation · 2D

Kerbal Space Program
Shared: Simulation · Sandbox · Education

Stardew Valley
Shared: Simulation · Pixel Graphics · Sandbox

Garry's Mod
Shared: Sandbox · Casual · Simulation

while True: learn()
Shared: Education · Simulation · Sandbox

My Dream Setup
Shared: Simulation · Sandbox · Casual

Terraria
Shared: Sandbox · 2D · Pixel Graphics

Graveyard Keeper
Shared: Simulation · Sandbox · Pixel Graphics

Sand:box
Shared: Simulation · Sandbox · 2D

Game Dev Tycoon
Shared: Simulation · Casual · 2D

The Sims™ 4
Shared: Simulation · Sandbox · Building

Cities: Skylines
Shared: Simulation · Sandbox · Building

Prison Architect
Shared: Simulation · Sandbox · Building

Project Highrise
Shared: Simulation · Sandbox · 2D

Townscaper
Shared: Sandbox · Simulation · Casual

Builder Simulator
Shared: Simulation · Sandbox · Education

Poly Bridge
Shared: Simulation · Sandbox · Building

Electrician Simulator
Shared: Simulation · Education · Immersive Sim

House Builder
Shared: Simulation · Education · Immersive Sim

Home Design 3D
Shared: Immersive Sim · Education · Sandbox

TheoTown
Shared: Simulation · Sandbox · Pixel Graphics

APICO
Shared: Sandbox · Education · Immersive Sim