Configuration

Configuration lives in three places: environment variables (build time), src/config/* (source defaults) and the Settings screens (runtime, per browser, stored in localStorage).

Runtime settings win over source defaults. Source defaults win over nothing — they are the defaults every new user sees.

Environment variables

Copy .env.example to .env.local. Every variable is NEXT_PUBLIC_, which means it is embedded in the browser bundle — never put secrets in them.

Variable	Default	Purpose
`NEXT_PUBLIC_APP_NAME`	`Numeralens`	Product name in titles and help
`NEXT_PUBLIC_API_URL`	(empty)	Backend base URL; empty uses the demo API routes
`NEXT_PUBLIC_ENABLE_DEMO_MODE`	`true`	`false` routes all data through the HTTP adapter
`NEXT_PUBLIC_AUTH_MODE`	`demo`	`demo`, `bearer` or `cookie`
`NEXT_PUBLIC_MOCK_LATENCY_MS`	`350`	Artificial latency so loading states are visible
`NEXT_PUBLIC_DEFAULT_CURRENCY`	`USD`	Formatting default
`NEXT_PUBLIC_DEFAULT_TIMEZONE`	`UTC`	Reporting timezone default
`NEXT_PUBLIC_DEFAULT_LOCALE`	`en-US`	Number and date locale default

Read into a typed object in src/config/app.config.ts.

Server-only (not NEXT_PUBLIC_):

Variable	Default	Purpose
`SITE_URL`	(Vercel: deployment URL)	Public base URL, e.g. `https://dash.example.com`, so link-share images resolve. Required when self-hosting.

Config files

File	Controls
`src/config/app.config.ts`	Environment-derived settings, request timeout
`src/config/branding.ts`	Company name, logo, colours, currency, formats, landing page
`src/config/features.ts`	The 17 feature flags and their descriptions
`src/config/roles.ts`	Roles, permissions and the role→permission matrix
`src/config/navigation.ts`	Sidebar structure and the route→feature-flag map

Feature flags

enableRevenue          enableExpenses         enableProfitability
enableCashFlow         enableReports          enableCustomers
enableVendors          enableTransactions     enableBudget
enableForecast         enableInventory        enableCustomDashboard
enableExport           enableNotifications    enableGlobalSearch

Turning a flag off does three things: the navigation entry disappears, the route renders a "module is turned off" screen (via the route→feature map in navigation.ts), and related widgets stop being offered in the widget library.

Change the shipped defaults in src/config/features.ts; end users toggle them at Settings → Modules and Settings → Feature flags.

To remove a module permanently, delete its folder under src/app/, its entry in navigation.ts and its flag.

Runtime settings and storage keys

All persisted under localStorage, namespaced so they are easy to clear:

Key	Written by
`numeralens.branding.v1`	Settings → Branding
`numeralens.features.v1`	Settings → Modules / Feature flags
`numeralens.api.v1`	Settings → Data source
`numeralens.filters.v1`	The global filter bar
`numeralens.auth.v1`	Demo auth provider (sign-in state and role)
`numeralens.custom-dashboard.v1`	Custom dashboard layout
`numeralens.notification-prefs.v1`	Settings → Notifications
`numeralens.sidebar.collapsed`	Sidebar collapse toggle

Clearing site data resets the app to the values in src/config/*.

To persist these server-side instead, replace useLocalStorage in the relevant provider with a query plus mutation against your API — the rest of the UI reads from context and does not care where the value came from.