Free interactive learning tool

The Coupling Matrix

Components on both axes, every dependency marked. The clusters are your real modules, whatever the org chart says — and where the two disagree is where your integration pain has been coming from all along.

Guess first — seven components, four teams

A platform has seven components and four teams. Integration work is painful and everyone agrees the teams need to communicate better — there have been joint stand-ups for two years. What most reliably predicts which pairs of components are painful to change together?

The matrix — click a cell to add or remove a dependency
What the grid says
The real modules
Conway conflicts
Turn the overlay on to see where the grid and the org chart disagree.
Where this bites
Reorgs

Moving the boxes

Reorganising teams without changing the coupling moves the pain rather than removing it. The matrix is the thing to redraw first; the org chart is downstream of it, whatever the announcement says.

Process

Stand-ups as a tax

Recurring cross-team ceremonies are usually the price of a boundary in the wrong place. They are worth paying only if you have decided not to move it — and mostly nobody has decided anything.

Vendors

The component that touches everything

A row that is dense across the whole grid is not a component, it is a substrate. Owning it inside one consuming team means everybody else queues behind that team’s priorities.

Non-software

It is not just systems

Draw the same grid with departments, or with the sign-offs a decision needs. The clusters are still real and still disagree with the reporting lines.

Draw this grid for anything you are about to reorganise, and draw it before the announcement. Two things that depend on each other both ways are one module, and splitting a module across two teams buys a permanent coordination cost that no amount of joint ceremony removes. Conway’s law is not a warning about culture — it is a statement that your architecture and your org chart will converge, and you get to choose which one leads.