Repository Architecture
This document describes the structural conventions used across the Polar Edge monorepo. Follow these patterns when adding features, refactoring, or creating new apps.
Monorepo Layout
The repository is a Turborepo monorepo managed with pnpm workspaces.
polar-edge/
├── apps/
│ ├── scouting/ # Main scouting app (Next.js 16 + Turbopack)
│ ├── basecamp/ # Backend service (NestJS, Discord bot, Sheets)
│ └── basecamp-fe/ # Frontend for Basecamp features (Next.js)
├── packages/
│ ├── ui/ # Shared Radix UI component library
│ ├── tba-sdk/ # The Blue Alliance API TypeScript client
│ ├── ai/ # Shared AI/LLM utilities
│ ├── twofa/ # Two-factor authentication utilities
│ ├── typescript-config/
│ └── vitest-config/
└── turbo.json
Key rules:
- Business logic lives in
apps/— packages are pure utilities with no app-specific logic. - Shared packages are consumed as workspace dependencies (
@repo/ui,@repo/tba-sdk, etc.). - Run tasks through Turbo:
turbo build,turbo dev --filter=scouting, etc. Don't run app scripts directly unless you have a reason.
Feature-First Architecture
Both Next.js apps (scouting and basecamp-fe) use a feature-first layout. The src/app/ directory is intentionally thin — it contains only Next.js routing files. All business logic, data access, and feature-specific components live in src/features/.
src/
├── app/ ← Routing only. Pages delegate to features.
├── features/ ← Primary home for all business logic.
│ └── <feature>/
│ ├── actions.ts # Server actions
│ ├── queries.ts # Database reads
│ ├── types.ts # Feature-specific types
│ ├── components/ # Feature-specific React components
│ ├── hooks/ # Feature-specific client hooks
│ └── contexts/ # Feature-specific React contexts
├── components/ ← Shared UI used across multiple features (nav, layout, etc.)
└── lib/ ← Pure utilities and library config. No feature logic.
The benefit: when you need to find or change anything about the "picklist" feature, you go to src/features/picklist/. You don't have to hunt across src/app/, src/utils/, src/api/, etc.
App Router Conventions
Pages are thin
Pages (page.tsx) should authenticate, load data, and compose feature components. They should not contain business logic themselves.
// ✅ Good — app/admin/members/page.tsx
export default function MembersPage() {
return (
<main className="container mx-auto max-w-5xl px-4 py-8">
<TypographyH1>Team Members</TypographyH1>
<Suspense fallback={<LoadingTable />}>
<MembersContent /> {/* async RSC from features/ */}
</Suspense>
</main>
);
}
The data-fetching and rendering logic lives in MembersContent, which is an async RSC imported from src/features/org/members/.
Async Server Components for data
Prefer async RSCs for data fetching. Place the async component in features/ and import it into the page:
// features/org/members/components/MembersContent.tsx
async function MembersContent() {
const activeMember = await requireAdminMember();
const members = await fetchMembers(activeMember.organizationId);
return <MembersTable members={members} />;
}
Suspense boundaries
Wrap async data-fetching components in <Suspense> in the page. Provide a meaningful skeleton as the fallback — not just a spinner. This enables streaming and prevents the whole page from blocking.
<Suspense fallback={<LoadingTable />}>
<MembersContent />
</Suspense>
Feature Module Anatomy
Each feature in src/features/<feature>/ follows this file structure. Not every file is required — only create what the feature needs:
| File / Directory | Purpose |
|---|---|
actions.ts |
Next.js Server Actions ("use server"). Mutations only — auth, validate, write DB. |
queries.ts |
Database reads. Always import "server-only". Use "use cache" for expensive reads. |
types.ts |
TypeScript types and interfaces specific to this feature. |
components/ |
React components used only by this feature. |
hooks/ |
Client-side React hooks used only by this feature. |
contexts/ |
React context providers used only by this feature. |
*.test.ts |
Tests co-located with the code they test. |
Example — picklist feature:
src/features/picklist/
├── actions.ts # createPicklist, deletePicklist, reorderTeams, etc.
├── queries.ts # getPicklistsForOrganization, etc.
├── types.ts # PicklistTeam, PicklistWithTeams, etc.
└── components/
├── CreatePicklistDialog.tsx
├── PicklistTeamsTable.tsx
├── DeletePicklistButton.tsx
└── ...
Example — nested features (org):
When a domain has sub-features with distinct concerns, nest them:
src/features/org/
├── settings/
│ ├── actions.ts
│ └── components/OrganizationSettingsForm.tsx
├── members/
│ ├── actions.ts
│ └── components/
│ ├── RemoveMemberButton.tsx
│ └── RoleSelect.tsx
└── invites/
├── actions.ts
└── components/InviteLinkManager.tsx
Server Actions Pattern
Server actions live in features/<feature>/actions.ts and always follow this order:
"use server";
export async function exampleAction(input: unknown) {
// 1. Authenticate — get session
const session = await auth.api.getSession({ headers: await headers() });
if (!session) return { error: "Unauthorized" };
// 2. Authorize — get active org member (role check if needed)
const member = await auth.api.getActiveMember({ headers: await headers() });
if (!member) return { error: "No active organization" };
// 3. Context — get active event if relevant
const event = await getActiveEventForOrganization(member.organizationId);
if (!event) return { error: "No active event" };
// 4. Validate input
const validated = schema.safeParse(input);
if (!validated.success) return { error: "Invalid input" };
// 5. Write — use a transaction for multi-table operations
const result = await db.transaction(async (tx) => {
// ... perform operations
return data;
});
// 6. Return success or error (never throw to the client)
return { success: true, data: result };
}
Rules:
- Always return
{ error: string }or{ success: true, ... }— never throw. - Use
db.transaction()when writing to multiple tables atomically. - Validate every external input with Zod before touching the database.
- Do not perform mutations from
queries.ts— keep reads and writes separate.
Data Queries & Caching
Database reads live in features/<feature>/queries.ts. Always mark this file as server-only:
import "server-only";
This prevents accidental import in client components and gives a clear build-time error if it happens.
Use "use cache" for expensive reads
For reads that are called frequently or are expensive, use Next.js's "use cache" directive with cacheLife and cacheTag:
import "server-only";
import { cacheLife, cacheTag } from "next/cache";
import { cacheTags } from "@/lib/cache";
export async function getStandFormCounts(
organizationId: string,
eventId: string | null
) {
"use cache";
cacheLife("hours");
cacheTag(cacheTags.leaderboardStand(organizationId));
return db
.select({ ... })
.from(standForm)
.where(...);
}
Cache tag centralization
All cache tag strings are defined in src/lib/cache.ts. Never hardcode tag strings at the call site — always use the cacheTags object:
// src/lib/cache.ts
export const cacheTags = {
leaderboardStand: (organizationId: string) => `leaderboard-stand-${organizationId}`,
teamMetrics: (eventId: string) => `team-metrics-${eventId}`,
// ...
};
When a mutation invalidates cached data, call revalidateTag(cacheTags.leaderboardStand(orgId)) in the relevant server action.
Parallel data fetching
When a page or component needs multiple independent pieces of data, fetch them in parallel with Promise.all:
const [organization, members] = await Promise.all([
auth.api.getFullOrganization({ ... }),
auth.api.listMembers({ ... }),
]);
RSC Boundaries — Server vs Client
Next.js components are Server Components by default. Only add "use client" when a component needs browser APIs, state, or event handlers.
Server Components (default)
- Fetch data directly (async/await)
- Access cookies, headers, environment variables
- Import server-only code (DB, auth, etc.)
- Cannot use
useState,useEffect, or browser APIs
Client Components ("use client")
- Interactive UI — event handlers, state, effects
- Browser APIs (
window,localStorage, timers) - Third-party client libraries
- React context providers that hold state
Minimize the client boundary
Push "use client" as deep into the component tree as possible. A good pattern: keep the page and data-fetching wrapper as RSCs, and only mark leaf components (buttons, forms, interactive widgets) as client:
// ✅ Good — page stays server, only the interactive button is client
// app/picklist/[id]/page.tsx (RSC)
export default async function PicklistPage({ params }) {
const picklist = await getPicklist(params.id); // server query
return <PicklistView picklist={picklist} />;
}
// features/picklist/components/DeletePicklistButton.tsx
"use client";
export function DeletePicklistButton({ id }) { ... }
Context providers
Context providers must be client components (they use React state internally). The pattern: create a <FeatureProvider> client component that wraps its children, and mount it as high as needed in the tree without making parent RSCs into client components.
// features/totp/contexts/TOTPContext.tsx
"use client";
export function TOTPProvider({ secret, children }) { ... }
// app/@auth/page.tsx (RSC — just renders the provider)
export default async function AuthPage() {
const secret = (await cookies()).get("toofaSecret")?.value;
return (
<TOTPProvider secret={secret}>
<FlipperWrapper />
</TOTPProvider>
);
}
Centralized Routes
All route paths are defined in src/lib/routes.ts. Never hardcode route strings in components or actions — always import from routes.
// src/lib/routes.ts
export const routes = {
home: "/",
admin: {
root: "/admin",
members: "/admin/members",
invites: "/admin/invites",
event: "/admin/event",
settings: "/admin/settings",
},
analysis: {
team: (teamNumber: number | string) => `/analysis/teams/${teamNumber}` as const,
},
// ...
} as const;
Usage:
import { routes } from "@/lib/routes";
<Link href={routes.admin.members}>Members</Link>
<Link href={routes.analysis.team(1234)}>Team 1234</Link>
Why: Refactoring a URL means changing one place. TypeScript catches broken references at build time.
Parallel Routes (Conditional UI)
When a page needs to show fundamentally different UI based on auth state (or another condition), use Next.js parallel routes rather than conditional rendering in a single component.
The basecamp-fe app uses this for its auth gate:
app/
├── layout.tsx # Renders both slots: {props.auth} and {props.unauth}
├── @auth/
│ └── page.tsx # Shown when authenticated
└── @unauth/
└── page.tsx # Shown when unauthenticated
// app/layout.tsx
export default function RootLayout(props: LayoutProps<"/">) {
return (
<html>
<body>
{props.unauth} {/* renders @unauth/page.tsx */}
{props.auth} {/* renders @auth/page.tsx */}
</body>
</html>
);
}
Each slot independently validates auth state and returns null if not applicable:
// app/@auth/page.tsx
export default async function AuthPage() {
const token = (await cookies()).get("toofaToken")?.value;
if (!token || !(await validateToken(token))) return null;
// render authenticated UI
}
// app/@unauth/page.tsx
export default async function UnauthorizedPage() {
const token = (await cookies()).get("toofaToken")?.value;
if (token && (await validateToken(token))) return null;
return <SignInForm />;
}
When to use parallel routes:
- Auth gates where the two states are visually distinct pages (not just a hidden button)
- Dashboard layouts with independently loading panels
- Modal overlays with intercepting routes
When NOT to use them: Simple show/hide toggles — use conditional rendering in a single component.
Shared UI Components
@repo/ui — cross-app design system
Radix UI primitives with Tailwind v4 styling. Import from the package path:
import { Button } from "@repo/ui/components/button";
import { Dialog, DialogContent, DialogTrigger } from "@repo/ui/components/dialog";
import { Table, TableBody, TableCell, TableHead } from "@repo/ui/components/table";
Use @repo/ui components as building blocks. Don't recreate primitives (buttons, inputs, dialogs) from scratch.
src/components/ — cross-feature app components
Components that are used by multiple features within the same app but aren't generic enough for @repo/ui:
Rule: If a component is only used by one feature, it belongs in src/features/<feature>/components/, not src/components/.
Lib Directory Rules
src/lib/ is for pure utilities and library configuration. It has no feature logic.
| Path | Contents |
|---|---|
lib/auth.ts |
Better Auth configuration |
lib/auth-client.ts |
Client-side auth helpers |
lib/permissions.ts |
Super admin checks |
lib/routes.ts |
Centralized route definitions |
lib/cache.ts |
Cache tag constants |
lib/utils.ts |
Generic utility functions (cn, etc.) |
lib/compress-image.ts |
Image compression utility |
lib/database/ |
Drizzle client, schema tables, relations, views, types |
lib/server/ |
Server-side helpers: auth guards, org helpers, storage, TBA, tokens |
lib/offline/ |
Network status, offline queue context, toasts |
What does NOT go in lib/:
- Feature-specific actions, queries, or components
- Anything that imports from
features/
Where Does My Code Go?
Use this decision tree when adding new code:
Is it a Next.js routing file (page, layout, loading, error)?
└─ Yes → src/app/<route>/
Is it a database read?
└─ Yes → src/features/<feature>/queries.ts (with "server-only" import)
Is it a mutation / form submission handler?
└─ Yes → src/features/<feature>/actions.ts (with "use server")
Is it a React component used only by one feature?
└─ Yes → src/features/<feature>/components/
Is it a React component used by multiple features?
└─ Yes → src/components/ (if app-specific) or packages/ui (if cross-app)
Is it a React hook used only by one feature?
└─ Yes → src/features/<feature>/hooks/
Is it a React context / provider for one feature?
└─ Yes → src/features/<feature>/contexts/
Is it a route path string?
└─ Yes → src/lib/routes.ts
Is it a cache tag string?
└─ Yes → src/lib/cache.ts
Is it a shared type for one feature?
└─ Yes → src/features/<feature>/types.ts
Is it a generic utility with no feature dependency?
└─ Yes → src/lib/utils.ts (or a new focused file in src/lib/)
Quick Reference
| Convention | Rule |
|---|---|
| Default RSC | All components are server by default; "use client" only when needed |
| Data fetching | Async RSC + queries.ts with "use cache" for expensive reads |
| Mutations | Server Actions in actions.ts; always auth → validate → transact → return |
| Routes | All paths in src/lib/routes.ts; never hardcode strings |
| Cache tags | All tags in src/lib/cache.ts via cacheTags object |
| Feature isolation | Each feature is self-contained; no cross-feature imports |
| Client boundary | Push "use client" as deep as possible |
server-only |
All queries.ts files start with import "server-only" |
| UI primitives | Use @repo/ui — don't reinvent buttons, dialogs, tables |
| Suspense | Wrap async RSCs in <Suspense> with skeleton fallbacks |
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