Malacca ran four harbormasters, one per merchant bloc

By the mid-15th century, Malacca had become a major crossroads port drawing Gujarati Muslim traders, South Indian and Bengali merchants, Southeast Asian traders, and Chinese and East Asian merchants into one harbor — a cosmopolitan community that reportedly numbered over 100,000 people. These groups shared essentially no common language, legal tradition, religious practice, or commercial custom with each other or with the Malay court running the port, and disputes over cargo, pricing or conduct were inevitable in a harbor moving that much foreign trade.

A single trade authority, however well-intentioned, would have had to adjudicate every dispute across radically different legal and cultural expectations with no shared reference point to draw on — a structural setup for perceived unfairness no matter which way any given ruling went, and slow, since one office would have had to become expert in every community's norms simultaneously.

Appointed four harbormasters, each from a merchant bloc, so disputes were settled by an insider who knew that community's norms, not a distant central office.

Each harbormaster was drawn from the community he served, so he already knew its language and customs.

Merchants trusted rulings from an insider, making decisions feel fair and legitimate.

Each harbormaster only needed expertise in one community's norms, so disputes were resolved faster.

The system scaled as Malacca grew, attracting more trade and becoming a major entrepôt.

When serving groups with incompatible norms, multiply authority: give each group its own representative from within, rather than one central arbiter.

The system let disputes and customs matters be handled locally within each merchant community by someone already fluent in its norms, rather than centrally by one office trying to arbitrate across all of them, and Malacca grew into the busiest entrepôt in the Indian Ocean trading world within a few decades of its founding around 1400.