Market

Origin

Market is Square's design system, public since the late 2010s, powering Square's seller-facing surfaces (POS, Dashboard, Online Store builder, Square Banking) and developer-facing surfaces (Sandbox, API docs). After Square became Block, the system continues to power the Square seller portfolio while sister brands like Cash App run their own.

Governance

Square's central design-systems team owns Market; component implementations are open-source on GitHub with documented contribution guidelines. The system ships across Web Components and React, with Figma libraries for design ecosystem.

Known for

• Money-handling input patterns — currency-aware inputs, transaction-row patterns, ledger-style data tables tuned for retail SMB use.
• Receipt and printing patterns — Square's POS produces physical receipts and the design system codifies the print and export formats.
• Cross-form-factor consistency — the same patterns translate from POS hardware (touch, large targets) to Dashboard (mouse, dense data) without forking.

Underrated

• The empty-state catalog for first-run sellers (no items yet, no orders yet, no team yet) is a reference for SMB onboarding — assumes users with no prior product knowledge.
• The product-listing patterns from Square Online (catalog management, bulk pricing, variant editor) cover real e-commerce edge cases most systems duck.

Watch out for

• Patterns assume retail SMB context — small staff, real-world transactions, mixed digital literacy. Lifting them onto enterprise B2B imports those assumptions.
• Visual identity is Square-flavored — black and white with restrained accents; consumer brands will need warmth.