Lendit

A book lending library for a group of people who already know each other: a team, a department, a book club. Members list the books they own, borrow each other's, and review each other afterwards.

It handles the awkward parts of lending between people: whether a copy is free for a given week, who still owes what, and what each side thought of the other once the book came back.

Contents

lendit-backend	REST API. Bun, Elysia, MongoDB, TypeScript
lendit-frontend	Web client. Vue 3, Vite, TypeScript

Each half has its own README with the detail. The API runs on its own; the client is useless without it.

Running both

The API first, since nothing in the client loads without it. It needs MongoDB as a replica set, because approvals and deletions run in transactions:

mongod --replSet rs0 --dbpath /your/data/path
mongosh --eval 'rs.initiate()'

cd lendit-backend
bun install
cp .env.example .env      # set MONGODB_URI and a real JWT_SECRET
bun run create-admin      # makes the first admin account
bun run dev               # http://localhost:3000

cd lendit-frontend
bun install
bun run dev               # http://localhost:5173

The client defaults to the API's own address, so a local setup needs no configuration. Sign up from the app to get a member account.

What it does

Borrowing is a conversation, not a switch

A book carries a number of copies, and availability is worked out per date range rather than as one in/out flag. Someone requests a book for a set of dates, the owner approves or declines, and approval is atomic: it re-checks availability at that moment and automatically rejects the pending requests it just filled up.

Both sides of every loan live on one page: what you have asked for, and what people have asked of you.

Your own shelf

Add the books you are willing to lend, with however many copies you own.

Reviews that go both ways

After a return, each side may rate the other once, within seven days. Reviews are attached to the loan they came from, so a profile shows what someone is like as a lender and as a borrower separately.

Admin

Admins manage the catalogue and moderate reviews, and do not borrow; the member pages are guarded, not merely hidden. The dashboard reports on any month.

Members can be suspended, which hides them from public views and drops their reviews out of everyone else's averages, without deleting anything.

On a phone

How it is built

API: routes, controllers, repositories and validators are kept apart, so every database query lives in one layer and every rule in another. Sessions are JWTs that can be revoked server-side. Two scheduled jobs clean up after people: requests that go stale are auto-rejected, and overdue loans auto-returned.

Client: one file per route, one composable per API resource, and a small set of L* primitives that everything else is built from. Every colour, size and radius is a token in styles/tokens.css. All UI copy lives in locales/en.json rather than in templates, so a second language means adding one file.

Both sides are TypeScript, both typecheck as part of their build, and both install with Bun, so there is one toolchain across the pair.