Stop Scattering if (role === 'admin') Everywhere: A 3-Level Permission Tree for Page & Section Access

Most apps start their access control with something like this: function canEditReportsSummary ( role ) { return [ ' EDITOR ' , ' ADMIN ' ]. includes ( role ); } It works, right up until you have a dozen pages, each with a few sections, each needing independent read/write rules per role. Now you've got dozens of these little arrays scattered across the codebase, and adding a new role means hunting down every single one and hoping you didn't miss any. 0 There's a much simpler model that scales cleanly: a three-level permission tree — page → section → { r, w } - plus one generic function that walks it. No new library, no framework lock-in, just a data structure and ~5 lines of code. The shape of the data Instead of scattering role checks in code, define one permission tree per role . Three levels deep: Page — the top-level feature/route ( dashboard , reports , settings ) Section — a sub-area within that page ( overview , summary , billing ) Action — r (read) or w (write) { "dashboard" : { "overview" : { "r" : true , "w" : false }, "analytics" : { "r" : true , "w" : false } }, "reports" : { "summary" : { "r" : true , "w" : false }, "export" : { "r" : false , "w" : false } }, "settings" : { "general" : { "r" : true , "w" : false }, "billing" : { "r" : false , "w" : false } } } This one blob fully describes what a single role can see and do. Give each role its own tree, e.g. for three common roles: Page Section Viewer Editor Admin dashboard overview r r, w r, w dashboard analytics r r r, w reports summary r r, w r, w reports export – r r, w settings general r r r, w settings billing – – r, w Notice how this reads almost like a spreadsheet a product owner could fill in — that's the point. It's declarative data, not scattered if statements, so non-engineers can review it and engineers don't have to guess what a role does. The generic access-check function Once permissions are just nested objects, checking access is one small, reusable, framework-agnostic function: function