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new → Better together: Southleft × Baseline, and a new CEO

<southleft>

AI-powered design systems. Built by the people building the tools.

We audit, build, and evolve design systems for teams at IBM, Google, PetSmart, and Toast — and we build the open-source AI tooling the design systems community actually uses. We don’t just talk about this stuff. We build it.

Trusted since 2012 by teams who care what’s under the hood.

  • IBM
  • Google
  • PetSmart
  • Toast
  • Caterpillar
  • Cigna Health
  • Condé Nast
  • DocuSign
  • State Farm
  • Ulta Beauty
  • CHUBB
  • Better.com

<why-now>

AI doesn’t replace your design system. It exposes it.

Systems built with structured context — clean tokens, typed components, real documentation — become force multipliers for AI-assisted teams. Systems without it become bottlenecks. We published a framework for getting from one to the other.

Read: Context-Based Design Systems →

<try-the-system>

Change one token. Everything agrees.

This is the entire argument for design systems: decisions live in tokens, not scattered across components. Flip a few — the product follows, instantly.

--sl-accent
--sl-radius
--sl-space
--sl-mode
--sl-display-wdth 125

Yes, really — this entire site runs on the same alias layer you're editing. Your theme sticks until you reset it.

acme-product / dashboard built on your system

<q3-report>

Design decisions, compounding.

Every element on this card reads the same five tokens you're editing. No component was touched.

214components
1source of truth
0rogue hex values
tokens a11y: AA mcp-ready

// --sl-accent: #f05735 · radius: 12px · space: 1 · mode: ink · wdth: 125

Now hand those same tokens to an AI agent over MCP and it ships UI that matches your product on the first pass — no rogue styles, no drift. Making that work inside real organizations is the work we do. Already fluent? Take the aptitude test — we grade on conviction.

<open-source>

We publish our homework

If we recommend a workflow, it’s because we’ve already built and shipped it. Open-source, in production, used by real teams.

They’re excellent! They make work seem easy — always on time and they communicate clearly along the way.
Jessi Hall — Producer, Big Medium
The team was very timely, often delivering even before the deadline and always being responsive.
Sara Soueidan — Inclusive Web Design Engineer & Educator
Southleft was instrumental in helping us improve our user experience while simultaneously increasing traffic and revenue.
Todd Hodgson — Director of Product Management, Outside Inc.
They go through a high level of detail to understand our needs and follow up to ensure their solutions meet them.
David Baucum — CTO, CURA Freight

<cta>

Is your design system AI-ready?

A 30-minute discovery call is the fastest way to find out where your leverage is.