2026-02-23 16:58:45 +00:00
26 changed files with 567 additions and 225 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -2,203 +2,125 @@

 This document describes the structure, conventions, and commands for the `vibe_coding_timetracker` monorepo. Read it in full before making changes.

---
-
 ## Repository Structure

-This is a monorepo with three sub-projects:
-
-```
+```text
 /
 ├── frontend/          # React SPA (Vite + TypeScript + Tailwind)
+│   └── src/
+│       ├── api/       # Axios API client modules
+│       ├── components/# Shared UI components (PascalCase .tsx)
+│       ├── contexts/  # React Context providers
+│       ├── hooks/     # TanStack React Query hooks (useXxx.ts)
+│       ├── pages/     # Route-level page components
+│       ├── types/     # TypeScript interfaces (index.ts)
+│       └── utils/     # Pure utility functions
 ├── backend/           # Express REST API (TypeScript + Prisma + PostgreSQL)
+│   └── src/
+│       ├── auth/      # OIDC + JWT logic
+│       ├── errors/    # AppError subclasses
+│       ├── middleware/# Express middlewares
+│       ├── prisma/    # Prisma client singleton
+│       ├── routes/    # Express routers (xxx.routes.ts)
+│       ├── schemas/   # Zod validation schemas
+│       └── services/  # Business logic classes (xxx.service.ts)
 ├── ios/               # Native iOS app (Swift/Xcode)
 ├── timetracker-chart/ # Helm chart for Kubernetes deployment
-├── docker-compose.yml
-└── project.md         # Product requirements document
+└── docker-compose.yml
 ```

-### Frontend layout (`frontend/src/`)
-```
-api/         # Axios API client modules (one file per resource)
-components/  # Shared UI components (PascalCase .tsx)
-contexts/    # React Context providers: AuthContext, TimerContext
-hooks/       # TanStack React Query custom hooks (useXxx.ts)
-pages/       # Route-level page components (XxxPage.tsx)
-types/       # All TypeScript interfaces (index.ts)
-utils/       # Pure utility functions (dateUtils.ts)
-```
-
-### Backend layout (`backend/src/`)
-```
-auth/        # OIDC + JWT authentication logic
-config/      # Environment variable configuration
-errors/      # Custom AppError subclasses
-middleware/  # auth, errorHandler, validation middleware
-prisma/      # Prisma client singleton
-routes/      # Express routers (xxx.routes.ts)
-schemas/     # Zod validation schemas (index.ts)
-services/    # Business logic classes (xxx.service.ts)
-types/       # TypeScript interfaces + Express augmentation
-utils/       # timeUtils.ts
-```
-
---
-
 ## Build, Lint, and Dev Commands

 ### Frontend (`frontend/`)
-```bash
-npm run dev       # Start Vite dev server (port 5173)
-npm run build     # Type-check (tsc) then bundle (vite build)
-npm run preview   # Preview production build locally
-npm run lint      # ESLint over .ts/.tsx, zero warnings allowed
-```
+- **Dev Server:** `npm run dev` (port 5173)
+- **Build:** `npm run build` (tsc & vite build)
+- **Lint:** `npm run lint` (ESLint, zero warnings allowed)
+- **Preview:** `npm run preview`

 ### Backend (`backend/`)
-```bash
-npm run dev          # Hot-reload dev server via tsx watch
-npm run build        # Compile TypeScript to dist/
-npm run start        # Run compiled output (node dist/index.js)
-npm run db:migrate   # Run Prisma migrations
-npm run db:generate  # Regenerate Prisma client
-npm run db:seed      # Seed the database
-```
+- **Dev Server:** `npm run dev` (tsx watch)
+- **Build:** `npm run build` (tsc to dist/)
+- **Start:** `npm run start` (node dist/index.js)
+- **Database:**
+  - `npm run db:migrate` (Run migrations)
+  - `npm run db:generate` (Regenerate client)
+  - `npm run db:seed` (Seed database)

-### Full stack (repo root)
-```bash
-docker-compose up    # Start all services (frontend, backend, postgres)
-```
+### Full Stack (Root)
+- **Run all:** `docker-compose up`

 ### Testing
-**There is no test framework configured.** No test runner (`jest`, `vitest`, etc.) is installed and no `.spec.ts` / `.test.ts` files exist. When adding tests, set up Vitest (already aligned with Vite) and add a `test` script to `package.json`. To run a single test file with Vitest once installed:
-```bash
-npx vitest run src/path/to/file.test.ts
-```
-
---
-
-## TypeScript Configuration
-
-### Frontend (`frontend/tsconfig.json`)
- `strict: true`, `noUnusedLocals: true`, `noUnusedParameters: true`
- `noEmit: true` — Vite handles all output
- Path alias `@/*` → `src/*` (use `@/` for all internal imports)
- `target: ES2020`, `module: ESNext`, `moduleResolution: bundler`
- `isolatedModules: true`, `resolveJsonModule: true`
-
-### Backend (`backend/tsconfig.json`)
- `strict: true`, `esModuleInterop: true`
- `target: ES2022`, `module: Node16`, `moduleResolution: Node16`
- `outDir: ./dist`, `rootDir: ./src`
- `declaration: true` (emits `.d.ts` files)
-
---
+**No test framework is currently configured.** No test runner (`jest`, `vitest`) is installed and no `.spec.ts` or `.test.ts` files exist.
+- When adding tests, set up **Vitest** (aligned with Vite).
+- Add a `test` script to `package.json`.
+- **To run a single test file with Vitest once installed:**
+  ```bash
+  npx vitest run src/path/to/file.test.ts
+  ```

 ## Code Style Guidelines

-### Imports
- Use the `@/` alias for all internal frontend imports: `import { useAuth } from "@/contexts/AuthContext"`
- Use `import type { ... }` for type-only imports: `import type { User } from "@/types"`
- Order: external libraries first, then internal `@/` imports
- Named exports are the standard; avoid default exports (only `App.tsx` uses one)
+### Imports & Exports
+- Use `@/` for all internal frontend imports: `import { useAuth } from "@/contexts/AuthContext"`
+- Use `import type { ... }` for type-only imports. Order external libraries first.
+- Named exports are standard. Avoid default exports (except in `App.tsx`).

 ### Formatting
- 2-space indentation throughout
- No Prettier config exists — maintain consistency with surrounding code
- Trailing commas in multi-line objects and arrays
- Quote style is mixed across the codebase (no enforcer); prefer double quotes to match the majority of files
+- 2-space indentation. No Prettier config exists; maintain consistency with surrounding code.
+- Prefer double quotes. Trailing commas in multi-line objects/arrays.

-### Types and Interfaces
- Define all shared types as `interface` (not `type` aliases) in the relevant `types/index.ts`
- Suffix input/mutation types: `CreateClientInput`, `UpdateProjectInput`
- Use `?` for optional fields, not `field: T | undefined`
- Use `string | null` for nullable fields (not `undefined`)
- Backend Zod schemas live in `backend/src/schemas/index.ts`, named `<Entity>Schema` (e.g., `CreateClientSchema`)
- Backend custom errors extend `AppError`: `NotFoundError`, `BadRequestError`, `ConflictError`, `UnauthorizedError`
-
-### Naming Conventions
-
-| Category | Convention | Example |
-|---|---|---|
-| React components | `PascalCase.tsx` | `TimerWidget.tsx`, `Modal.tsx` |
-| Page components | `PascalCasePage.tsx` | `DashboardPage.tsx`, `LoginPage.tsx` |
-| Context files | `PascalCaseContext.tsx` | `AuthContext.tsx`, `TimerContext.tsx` |
-| Custom hooks | `useXxx.ts` | `useTimeEntries.ts`, `useClients.ts` |
-| API modules | `camelCase.ts` | `timeEntries.ts`, `clients.ts` |
-| Utility files | `camelCaseUtils.ts` | `dateUtils.ts`, `timeUtils.ts` |
-| Backend routes | `camelCase.routes.ts` | `timeEntry.routes.ts` |
-| Backend services | `camelCase.service.ts` | `timeEntry.service.ts` |
-| Types / schemas | `index.ts` (aggregated) | `src/types/index.ts` |
-| Directories | `camelCase` | `api/`, `hooks/`, `routes/`, `services/` |
+### Types & Naming Conventions
+- Define shared types as `interface` in `types/index.ts`.
+- Suffix input types: `CreateClientInput`.
+- Use `?` for optional fields, `string | null` for nullable fields (not `undefined`).
+- **Components:** `PascalCase.tsx` (`DashboardPage.tsx`)
+- **Hooks/Utils/API:** `camelCase.ts` (`useTimeEntries.ts`, `dateUtils.ts`)
+- **Backend Routes/Services:** `camelCase.routes.ts`, `camelCase.service.ts`
+- **Backend Schemas:** Zod schemas in `backend/src/schemas/index.ts` (e.g., `CreateClientSchema`).

 ### React Components
- Use named function declarations, not arrow functions assigned to `const`:
-  ```ts
-  // correct
-  export function DashboardPage() { ... }
-
-  // avoid
-  export const DashboardPage = () => { ... }
-  ```
- Context hooks (`useAuth`, `useTimer`) throw an error if called outside their provider — maintain this pattern for all new contexts
+- Use named function declarations: `export function DashboardPage() { ... }`
+- Context hooks throw an error if called outside their provider.

 ### State Management
- **Server state**: TanStack React Query (all remote data). Never use `useState` for server data.
-  - Custom hooks encapsulate `useQuery` + `useMutation` + cache invalidation
-  - Query keys are arrays: `["timeEntries", filters]`, `["projects", clientId]`
-  - Use `mutateAsync` (not `mutate`) so callers can `await` and handle errors
-  - Invalidate related queries after mutations via `queryClient.invalidateQueries`
- **Shared client state**: React Context (`AuthContext`, `TimerContext`)
- **Local UI state**: `useState` per component (modals, form data, error messages)
- No Redux or Zustand — do not introduce them
+- **Server state:** TanStack React Query. Never use `useState` for server data.
+  - Use `mutateAsync` so callers can await and handle errors.
+  - Invalidate related queries after mutations: `queryClient.invalidateQueries`.
+- **Shared client state:** React Context.
+- **Local UI state:** `useState`.
+- **NO Redux or Zustand.**

 ### Error Handling
-
-**Frontend:**
-```ts
-try {
-  await someAsyncOperation()
-} catch (err) {
-  setError(err instanceof Error ? err.message : "An error occurred")
-}
-```
- Store errors in local `useState<string | null>` and render inline as red text
- No global error boundary exists; handle errors close to where they occur
-
-**Backend:**
-```ts
-router.get("/resource/:id", async (req, res, next) => {
+- **Frontend:**
+  ```typescript
  try {
-    const result = await service.getById(req.params.id)
-    res.json(result)
-  } catch (error) {
-    next(error) // always forward to errorHandler middleware
+    await someAsyncOperation()
+  } catch (err) {
+    setError(err instanceof Error ? err.message : "An error occurred")
  }
-})
-```
- Throw `AppError` subclasses from services; never send raw error responses from route handlers
- The global `errorHandler` middleware handles Prisma error codes (P2002, P2025, P2003) and `AppError` subclasses
+  ```
+  Store errors in local state and render inline as red text. No global error boundary exists.
+- **Backend:** Throw `AppError` subclasses from services.
+  ```typescript
+  router.get("/:id", async (req, res, next) => {
+    try {
+      res.json(await service.getById(req.params.id))
+    } catch (error) {
+      next(error) // Always forward to errorHandler middleware
+    }
+  })
+  ```

 ### Styling
- **Tailwind CSS v3** for all styling — no CSS modules, no styled-components
- Use `clsx` + `tailwind-merge` for conditional class merging when needed
- Icons from `lucide-react` only
+- **Tailwind CSS v3** only. No CSS modules or styled-components.
+- Use `clsx` + `tailwind-merge` for class merging. Icons from `lucide-react` only.

-### Backend Validation
- All incoming request data validated with Zod schemas before reaching service layer
- Schemas defined in `backend/src/schemas/index.ts`
- Validation middleware applied per-route; never trust `req.body` without parsing through a schema
-
-### Database
- Prisma v6 with PostgreSQL
- Database column names are `snake_case`, mapped to `camelCase` TypeScript via `@map` in the Prisma schema
- Always use the Prisma client singleton from `backend/src/prisma/`
-
---
+### Backend Validation & Database
+- Validate all incoming request data with Zod schemas in middleware.
+- Prisma v6 with PostgreSQL. Use the Prisma client singleton from `backend/src/prisma/`.
+- DB columns are `snake_case`, mapped to `camelCase` TypeScript via `@map`.

 ## Key Architectural Decisions
- The frontend communicates with the backend exclusively through the typed Axios modules in `frontend/src/api/`
- Authentication supports two flows: OIDC (web, via `express-session`) and JWT (iOS client, via `jsonwebtoken`)
- The iOS app lives in `ios/` and shares no code with the web frontend — do not couple them
- All business logic belongs in service classes; routes only handle HTTP concerns (parsing, validation, response formatting)
+- Frontend communicates with Backend exclusively via typed Axios modules in `frontend/src/api/`.
+- iOS app shares no code with the web frontend.
+- Backend routes only handle HTTP concerns (parsing, validation, formatting); business logic belongs purely in services.
--- a/backend/package-lock.json
+++ b/backend/package-lock.json
@@ -9,6 +9,7 @@
      "version": "1.0.0",
      "dependencies": {
        "@prisma/client": "^6.19.2",
+        "@quixo3/prisma-session-store": "^3.1.19",
        "cors": "^2.8.5",
        "dotenv": "^17.3.1",
        "express": "^4.18.2",
@@ -470,6 +471,27 @@
        "node": ">=18"
      }
    },
+    "node_modules/@noble/hashes": {
+      "version": "1.8.0",
+      "resolved": "https://registry.npmjs.org/@noble/hashes/-/hashes-1.8.0.tgz",
+      "integrity": "sha512-jCs9ldd7NwzpgXDIf6P3+NrHh9/sD6CQdxHyjQI+h/6rDNo88ypBxxz45UDuZHz9r3tNz7N/VInSVoVdtXEI4A==",
+      "license": "MIT",
+      "engines": {
+        "node": "^14.21.3 || >=16"
+      },
+      "funding": {
+        "url": "https://paulmillr.com/funding/"
+      }
+    },
+    "node_modules/@paralleldrive/cuid2": {
+      "version": "2.3.1",
+      "resolved": "https://registry.npmjs.org/@paralleldrive/cuid2/-/cuid2-2.3.1.tgz",
+      "integrity": "sha512-XO7cAxhnTZl0Yggq6jOgjiOHhbgcO4NqFqwSmQpjK3b6TEE6Uj/jfSk6wzYyemh3+I0sHirKSetjQwn5cZktFw==",
+      "license": "MIT",
+      "dependencies": {
+        "@noble/hashes": "^1.1.5"
+      }
+    },
    "node_modules/@prisma/client": {
      "version": "6.19.2",
      "resolved": "https://registry.npmjs.org/@prisma/client/-/client-6.19.2.tgz",
@@ -555,6 +577,24 @@
        "@prisma/debug": "6.19.2"
      }
    },
+    "node_modules/@quixo3/prisma-session-store": {
+      "version": "3.1.19",
+      "resolved": "https://registry.npmjs.org/@quixo3/prisma-session-store/-/prisma-session-store-3.1.19.tgz",
+      "integrity": "sha512-fCG7dzmd8dyqoj4XSi5IHETqrbzN+roz4+4pPS1uMo0kVQu8CT9HRbULuIaOxWCAODT7yGyNGNvVywEeGI80lw==",
+      "license": "MIT",
+      "dependencies": {
+        "@paralleldrive/cuid2": "^2.2.0",
+        "ts-dedent": "^2.2.0",
+        "type-fest": "^5.3.1"
+      },
+      "engines": {
+        "node": ">=12.0"
+      },
+      "peerDependencies": {
+        "@prisma/client": ">=2.16.1",
+        "express-session": ">=1.17.1"
+      }
+    },
    "node_modules/@standard-schema/spec": {
      "version": "1.1.0",
      "resolved": "https://registry.npmjs.org/@standard-schema/spec/-/spec-1.1.0.tgz",
@@ -2133,6 +2173,18 @@
        "node": ">= 0.8"
      }
    },
+    "node_modules/tagged-tag": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/tagged-tag/-/tagged-tag-1.0.0.tgz",
+      "integrity": "sha512-yEFYrVhod+hdNyx7g5Bnkkb0G6si8HJurOoOEgC8B/O0uXLHlaey/65KRv6cuWBNhBgHKAROVpc7QyYqE5gFng==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=20"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
    "node_modules/tinyexec": {
      "version": "1.0.2",
      "resolved": "https://registry.npmjs.org/tinyexec/-/tinyexec-1.0.2.tgz",
@@ -2152,6 +2204,15 @@
        "node": ">=0.6"
      }
    },
+    "node_modules/ts-dedent": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/ts-dedent/-/ts-dedent-2.2.0.tgz",
+      "integrity": "sha512-q5W7tVM71e2xjHZTlgfTDoPF/SmqKG5hddq9SzR49CH2hayqRKJtQ4mtRlSxKaJlR/+9rEM+mnBHf7I2/BQcpQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=6.10"
+      }
+    },
    "node_modules/tsx": {
      "version": "4.21.0",
      "resolved": "https://registry.npmjs.org/tsx/-/tsx-4.21.0.tgz",
@@ -2172,6 +2233,21 @@
        "fsevents": "~2.3.3"
      }
    },
+    "node_modules/type-fest": {
+      "version": "5.4.4",
+      "resolved": "https://registry.npmjs.org/type-fest/-/type-fest-5.4.4.tgz",
+      "integrity": "sha512-JnTrzGu+zPV3aXIUhnyWJj4z/wigMsdYajGLIYakqyOW1nPllzXEJee0QQbHj+CTIQtXGlAjuK0UY+2xTyjVAw==",
+      "license": "(MIT OR CC0-1.0)",
+      "dependencies": {
+        "tagged-tag": "^1.0.0"
+      },
+      "engines": {
+        "node": ">=20"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
    "node_modules/type-is": {
      "version": "1.6.18",
      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.18.tgz",
--- a/backend/package.json
+++ b/backend/package.json
@@ -11,6 +11,7 @@
  },
  "dependencies": {
    "@prisma/client": "^6.19.2",
+    "@quixo3/prisma-session-store": "^3.1.19",
    "cors": "^2.8.5",
    "dotenv": "^17.3.1",
    "express": "^4.18.2",
--- a/backend/prisma/migrations/20260223103350_add_session_model/migration.sql
+++ b/backend/prisma/migrations/20260223103350_add_session_model/migration.sql
@@ -0,0 +1,12 @@
+-- CreateTable
+CREATE TABLE "sessions" (
+    "id" TEXT NOT NULL,
+    "sid" TEXT NOT NULL,
+    "data" TEXT NOT NULL,
+    "expires_at" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "sessions_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "sessions_sid_key" ON "sessions"("sid");
--- a/backend/prisma/migrations/20260223123527_add_break_minutes/migration.sql
+++ b/backend/prisma/migrations/20260223123527_add_break_minutes/migration.sql
@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "time_entries" ADD COLUMN "break_minutes" INTEGER NOT NULL DEFAULT 0;
--- a/backend/prisma/schema.prisma
+++ b/backend/prisma/schema.prisma
@@ -10,7 +10,7 @@ datasource db {
 model User {
  id        String   @id @db.VarChar(255)
  username  String   @db.VarChar(255)
-  fullName  String?  @db.VarChar(255) @map("full_name")
+  fullName  String?  @map("full_name") @db.VarChar(255)
  email     String   @db.VarChar(255)
  createdAt DateTime @default(now()) @map("created_at")
  updatedAt DateTime @updatedAt @map("updated_at")
@@ -31,9 +31,9 @@ model Client {
  createdAt   DateTime @default(now()) @map("created_at")
  updatedAt   DateTime @updatedAt @map("updated_at")

-  userId   String @map("user_id") @db.VarChar(255)
-  user     User   @relation(fields: [userId], references: [id], onDelete: Cascade)
-  projects Project[]
+  userId        String         @map("user_id") @db.VarChar(255)
+  user          User           @relation(fields: [userId], references: [id], onDelete: Cascade)
+  projects      Project[]
  clientTargets ClientTarget[]

  @@index([userId])
@@ -41,10 +41,10 @@ model Client {
 }

 model Project {
-  id          String  @id @default(uuid())
-  name        String  @db.VarChar(255)
-  description String? @db.Text
-  color       String? @db.VarChar(7) // Hex color code
+  id          String   @id @default(uuid())
+  name        String   @db.VarChar(255)
+  description String?  @db.Text
+  color       String?  @db.VarChar(7) // Hex color code
  createdAt   DateTime @default(now()) @map("created_at")
  updatedAt   DateTime @updatedAt @map("updated_at")

@@ -53,7 +53,7 @@ model Project {
  clientId String @map("client_id")
  client   Client @relation(fields: [clientId], references: [id], onDelete: Cascade)

-  timeEntries  TimeEntry[]
+  timeEntries   TimeEntry[]
  ongoingTimers OngoingTimer[]

  @@index([userId])
@@ -62,16 +62,17 @@ model Project {
 }

 model TimeEntry {
-  id          String   @id @default(uuid())
-  startTime   DateTime @map("start_time") @db.Timestamptz()
-  endTime     DateTime @map("end_time") @db.Timestamptz()
-  description String?  @db.Text
-  createdAt   DateTime @default(now()) @map("created_at")
-  updatedAt   DateTime @updatedAt @map("updated_at")
+  id           String   @id @default(uuid())
+  startTime    DateTime @map("start_time") @db.Timestamptz()
+  endTime      DateTime @map("end_time") @db.Timestamptz()
+  breakMinutes Int      @default(0) @map("break_minutes")
+  description  String?  @db.Text
+  createdAt    DateTime @default(now()) @map("created_at")
+  updatedAt    DateTime @updatedAt @map("updated_at")

-  userId    String @map("user_id") @db.VarChar(255)
-  user      User   @relation(fields: [userId], references: [id], onDelete: Cascade)
-  projectId String @map("project_id")
+  userId    String  @map("user_id") @db.VarChar(255)
+  user      User    @relation(fields: [userId], references: [id], onDelete: Cascade)
+  projectId String  @map("project_id")
  project   Project @relation(fields: [projectId], references: [id], onDelete: Cascade)

  @@index([userId])
@@ -86,9 +87,9 @@ model OngoingTimer {
  createdAt DateTime @default(now()) @map("created_at")
  updatedAt DateTime @updatedAt @map("updated_at")

-  userId    String  @map("user_id") @db.VarChar(255) @unique
-  user      User    @relation(fields: [userId], references: [id], onDelete: Cascade)
-  projectId String? @map("project_id")
+  userId    String   @unique @map("user_id") @db.VarChar(255)
+  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)
+  projectId String?  @map("project_id")
  project   Project? @relation(fields: [projectId], references: [id], onDelete: SetNull)

  @@index([userId])
@@ -96,11 +97,11 @@ model OngoingTimer {
 }

 model ClientTarget {
-  id           String   @id @default(uuid())
-  weeklyHours  Float    @map("weekly_hours")
-  startDate    DateTime @map("start_date") @db.Date // Always a Monday
-  createdAt    DateTime @default(now()) @map("created_at")
-  updatedAt    DateTime @updatedAt @map("updated_at")
+  id          String   @id @default(uuid())
+  weeklyHours Float    @map("weekly_hours")
+  startDate   DateTime @map("start_date") @db.Date // Always a Monday
+  createdAt   DateTime @default(now()) @map("created_at")
+  updatedAt   DateTime @updatedAt @map("updated_at")

  userId   String @map("user_id") @db.VarChar(255)
  user     User   @relation(fields: [userId], references: [id], onDelete: Cascade)
@@ -128,4 +129,13 @@ model BalanceCorrection {

  @@index([clientTargetId])
  @@map("balance_corrections")
-}
+}
+
+model Session {
+  id        String   @id
+  sid       String   @unique
+  data      String   @db.Text
+  expiresAt DateTime @map("expires_at")
+
+  @@map("sessions")
+}
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -1,8 +1,9 @@
 import express from "express";
 import cors from "cors";
 import session from "express-session";
+import { PrismaSessionStore } from "@quixo3/prisma-session-store";
 import { config, validateConfig } from "./config";
-import { connectDatabase } from "./prisma/client";
+import { connectDatabase, prisma } from "./prisma/client";
 import { errorHandler, notFoundHandler } from "./middleware/errorHandler";

 // Import routes
@@ -43,6 +44,11 @@ async function main() {
      resave: false,
      saveUninitialized: false,
      name: "sessionId",
+      store: new PrismaSessionStore(prisma, {
+        checkPeriod: 2 * 60 * 1000, // ms
+        dbRecordIdIsSessionId: true,
+        dbRecordIdFunction: undefined,
+      }),
      cookie: {
        secure: config.nodeEnv === "production",
        httpOnly: true,
--- a/backend/src/routes/timer.routes.ts
+++ b/backend/src/routes/timer.routes.ts
@@ -48,6 +48,16 @@ router.put(
  }
 );

+// DELETE /api/timer - Cancel (discard) the ongoing timer without creating a time entry
+router.delete('/', requireAuth, async (req: AuthenticatedRequest, res, next) => {
+  try {
+    await timerService.cancel(req.user!.id);
+    res.status(204).send();
+  } catch (error) {
+    next(error);
+  }
+});
+
 // POST /api/timer/stop - Stop timer
 router.post(
  '/stop',
--- a/backend/src/schemas/index.ts
+++ b/backend/src/schemas/index.ts
@@ -31,6 +31,7 @@ export const UpdateProjectSchema = z.object({
 export const CreateTimeEntrySchema = z.object({
  startTime: z.string().datetime(),
  endTime: z.string().datetime(),
+  breakMinutes: z.number().int().min(0).optional(),
  description: z.string().max(1000).optional(),
  projectId: z.string().uuid(),
 });
@@ -38,6 +39,7 @@ export const CreateTimeEntrySchema = z.object({
 export const UpdateTimeEntrySchema = z.object({
  startTime: z.string().datetime().optional(),
  endTime: z.string().datetime().optional(),
+  breakMinutes: z.number().int().min(0).optional(),
  description: z.string().max(1000).optional(),
  projectId: z.string().uuid().optional(),
 });
@@ -64,6 +66,7 @@ export const StartTimerSchema = z.object({

 export const UpdateTimerSchema = z.object({
  projectId: z.string().uuid().optional().nullable(),
+  startTime: z.string().datetime().optional(),
 });

 export const StopTimerSchema = z.object({
--- a/backend/src/services/clientTarget.service.ts
+++ b/backend/src/services/clientTarget.service.ts
@@ -222,7 +222,7 @@ export class ClientTargetService {
    const rows = await prisma.$queryRaw<TrackedRow[]>(Prisma.sql`
      SELECT
        DATE_TRUNC('week', te.start_time AT TIME ZONE 'UTC') AS week_start,
-        COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time))), 0)::bigint AS tracked_seconds
+        COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time)) - (te.break_minutes * 60)), 0)::bigint AS tracked_seconds
      FROM time_entries te
      JOIN projects p ON p.id = te.project_id
      WHERE te.user_id = ${target.userId}
--- a/backend/src/services/timeEntry.service.ts
+++ b/backend/src/services/timeEntry.service.ts
@@ -42,7 +42,7 @@ export class TimeEntryService {
          p.id   AS project_id,
          p.name AS project_name,
          p.color AS project_color,
-          COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time))), 0)::bigint AS total_seconds,
+          COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time)) - (te.break_minutes * 60)), 0)::bigint AS total_seconds,
          COUNT(te.id)::bigint AS entry_count
        FROM time_entries te
        JOIN projects p ON p.id = te.project_id
@@ -63,7 +63,7 @@ export class TimeEntryService {
        SELECT
          c.id   AS client_id,
          c.name AS client_name,
-          COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time))), 0)::bigint AS total_seconds,
+          COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time)) - (te.break_minutes * 60)), 0)::bigint AS total_seconds,
          COUNT(te.id)::bigint AS entry_count
        FROM time_entries te
        JOIN projects p ON p.id = te.project_id
@@ -77,7 +77,7 @@ export class TimeEntryService {
      prisma.$queryRaw<{ total_seconds: bigint; entry_count: bigint }[]>(
        Prisma.sql`
          SELECT
-            COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time))), 0)::bigint AS total_seconds,
+            COALESCE(SUM(EXTRACT(EPOCH FROM (te.end_time - te.start_time)) - (te.break_minutes * 60)), 0)::bigint AS total_seconds,
            COUNT(te.id)::bigint AS entry_count
          FROM time_entries te
          JOIN projects p ON p.id = te.project_id
@@ -204,12 +204,19 @@ export class TimeEntryService {
  async create(userId: string, data: CreateTimeEntryInput) {
    const startTime = new Date(data.startTime);
    const endTime = new Date(data.endTime);
+    const breakMinutes = data.breakMinutes ?? 0;

    // Validate end time is after start time
    if (endTime <= startTime) {
      throw new BadRequestError("End time must be after start time");
    }

+    // Validate break time doesn't exceed duration
+    const durationMinutes = (endTime.getTime() - startTime.getTime()) / 60000;
+    if (breakMinutes > durationMinutes) {
+      throw new BadRequestError("Break time cannot exceed total duration");
+    }
+
    // Verify the project belongs to the user
    const project = await prisma.project.findFirst({
      where: { id: data.projectId, userId },
@@ -235,6 +242,7 @@ export class TimeEntryService {
      data: {
        startTime,
        endTime,
+        breakMinutes,
        description: data.description,
        userId,
        projectId: data.projectId,
@@ -267,12 +275,19 @@ export class TimeEntryService {
      ? new Date(data.startTime)
      : entry.startTime;
    const endTime = data.endTime ? new Date(data.endTime) : entry.endTime;
+    const breakMinutes = data.breakMinutes ?? entry.breakMinutes;

    // Validate end time is after start time
    if (endTime <= startTime) {
      throw new BadRequestError("End time must be after start time");
    }

+    // Validate break time doesn't exceed duration
+    const durationMinutes = (endTime.getTime() - startTime.getTime()) / 60000;
+    if (breakMinutes > durationMinutes) {
+      throw new BadRequestError("Break time cannot exceed total duration");
+    }
+
    // If project changed, verify it belongs to the user
    if (data.projectId && data.projectId !== entry.projectId) {
      const project = await prisma.project.findFirst({
@@ -302,6 +317,7 @@ export class TimeEntryService {
      data: {
        startTime,
        endTime,
+        breakMinutes,
        description: data.description,
        projectId: data.projectId,
      },
--- a/backend/src/services/timer.service.ts
+++ b/backend/src/services/timer.service.ts
@@ -102,9 +102,24 @@ export class TimerService {
      projectId = data.projectId;
    }

+    // Validate startTime if provided
+    let startTime: Date | undefined = undefined;
+    if (data.startTime) {
+      const parsed = new Date(data.startTime);
+      const now = new Date();
+      if (parsed >= now) {
+        throw new BadRequestError("Start time must be in the past");
+      }
+      startTime = parsed;
+    }
+
+    const updateData: Record<string, unknown> = {};
+    if (projectId !== undefined) updateData.projectId = projectId;
+    if (startTime !== undefined) updateData.startTime = startTime;
+
    return prisma.ongoingTimer.update({
      where: { userId },
-      data: projectId !== undefined ? { projectId } : {},
+      data: updateData,
      include: {
        project: {
          select: {
@@ -123,6 +138,15 @@ export class TimerService {
    });
  }

+  async cancel(userId: string) {
+    const timer = await this.getOngoingTimer(userId);
+    if (!timer) {
+      throw new NotFoundError("No timer is running");
+    }
+
+    await prisma.ongoingTimer.delete({ where: { userId } });
+  }
+
  async stop(userId: string, data?: StopTimerInput) {
    const timer = await this.getOngoingTimer(userId);
    if (!timer) {
--- a/backend/src/types/index.ts
+++ b/backend/src/types/index.ts
@@ -38,6 +38,7 @@ export interface UpdateProjectInput {
 export interface CreateTimeEntryInput {
  startTime: string;
  endTime: string;
+  breakMinutes?: number;
  description?: string;
  projectId: string;
 }
@@ -45,6 +46,7 @@ export interface CreateTimeEntryInput {
 export interface UpdateTimeEntryInput {
  startTime?: string;
  endTime?: string;
+  breakMinutes?: number;
  description?: string;
  projectId?: string;
 }
@@ -71,6 +73,7 @@ export interface StartTimerInput {

 export interface UpdateTimerInput {
  projectId?: string | null;
+  startTime?: string;
 }

 export interface StopTimerInput {
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -2,7 +2,7 @@
 <html lang="en">
  <head>
    <meta charset="UTF-8" />
-    <link rel="icon" type="image/svg+xml" href="/vite.svg" />
+    <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>TimeTracker</title>
  </head>
--- a/frontend/public/favicon.svg
+++ b/frontend/public/favicon.svg
@@ -0,0 +1,40 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="48 48 416 416" width="100%" height="100%">
+  <defs>
+    <linearGradient id="bg" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#818CF8" />
+      <stop offset="100%" stop-color="#4F46E5" />
+    </linearGradient>
+  </defs>
+
+  <!-- App Icon Background -->
+  <rect x="48" y="48" width="416" height="416" rx="96" fill="url(#bg)" />
+
+  <!-- Inner Icon Group -->
+  <g stroke="#ffffff" fill="none" stroke-linecap="round" stroke-linejoin="round">
+    <!-- Stopwatch Top Button -->
+    <path d="M256 96 v44" stroke-width="28" />
+    <path d="M224 88 h64" stroke-width="24" />
+
+    <!-- Stopwatch Side Button -->
+    <path d="M352 176 l 24 -24" stroke-width="24" />
+    <!-- Cap for side button -->
+    <path d="M362 138 l 28 28" stroke-width="24" />
+
+    <!-- Outer Ring -->
+    <circle cx="256" cy="272" r="132" stroke-width="28" />
+
+    <!-- Clock Hands -->
+    <!-- Minute Hand -->
+    <path d="M256 184 v 88" stroke-width="24" />
+    <!-- Hour Hand -->
+    <path d="M256 272 l 48 32" stroke-width="24" />
+
+    <!-- Dial Tick Marks -->
+    <g stroke-width="12" opacity="0.6">
+      <line x1="256" y1="172" x2="256" y2="188" />
+      <line x1="256" y1="356" x2="256" y2="372" />
+      <line x1="172" y1="272" x2="188" y2="272" />
+      <line x1="340" y1="272" x2="324" y2="272" />
+    </g>
+  </g>
+</svg>
--- a/frontend/public/icon.svg
+++ b/frontend/public/icon.svg
@@ -0,0 +1,43 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" width="100%" height="100%">
+  <defs>
+    <linearGradient id="bg" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#818CF8" />
+      <stop offset="100%" stop-color="#4F46E5" />
+    </linearGradient>
+    <filter id="shadow" x="-20%" y="-20%" width="140%" height="140%">
+      <feDropShadow dx="0" dy="12" stdDeviation="16" flood-color="#4F46E5" flood-opacity="0.4" />
+    </filter>
+  </defs>
+
+  <!-- App Icon Background -->
+  <rect x="48" y="48" width="416" height="416" rx="96" fill="url(#bg)" filter="url(#shadow)" />
+
+  <!-- Inner Icon Group -->
+  <g stroke="#ffffff" fill="none" stroke-linecap="round" stroke-linejoin="round">
+    <!-- Stopwatch Top Button -->
+    <path d="M256 96 v44" stroke-width="28" />
+    <path d="M224 88 h64" stroke-width="24" />
+    
+    <!-- Stopwatch Side Button -->
+    <path d="M352 176 l 24 -24" stroke-width="24" />
+    <!-- Cap for side button -->
+    <path d="M362 138 l 28 28" stroke-width="24" />
+
+    <!-- Outer Ring -->
+    <circle cx="256" cy="272" r="132" stroke-width="28" />
+    
+    <!-- Clock Hands -->
+    <!-- Minute Hand -->
+    <path d="M256 184 v 88" stroke-width="24" />
+    <!-- Hour Hand -->
+    <path d="M256 272 l 48 32" stroke-width="24" />
+
+    <!-- Dial Tick Marks -->
+    <g stroke-width="12" opacity="0.6">
+      <line x1="256" y1="172" x2="256" y2="188" />
+      <line x1="256" y1="356" x2="256" y2="372" />
+      <line x1="172" y1="272" x2="188" y2="272" />
+      <line x1="340" y1="272" x2="324" y2="272" />
+    </g>
+  </g>
+</svg>
--- a/frontend/src/api/timer.ts
+++ b/frontend/src/api/timer.ts
@@ -1,6 +1,11 @@
 import apiClient from './client';
 import type { OngoingTimer, TimeEntry } from '@/types';

+export interface UpdateTimerPayload {
+  projectId?: string | null;
+  startTime?: string;
+}
+
 export const timerApi = {
  getOngoing: async (): Promise<OngoingTimer | null> => {
    const { data } = await apiClient.get<OngoingTimer | null>('/timer');
@@ -14,10 +19,8 @@ export const timerApi = {
    return data;
  },

-  update: async (projectId?: string | null): Promise<OngoingTimer> => {
-    const { data } = await apiClient.put<OngoingTimer>('/timer', {
-      projectId,
-    });
+  update: async (payload: UpdateTimerPayload): Promise<OngoingTimer> => {
+    const { data } = await apiClient.put<OngoingTimer>('/timer', payload);
    return data;
  },

@@ -27,4 +30,8 @@ export const timerApi = {
    });
    return data;
  },
+
+  cancel: async (): Promise<void> => {
+    await apiClient.delete('/timer');
+  },
 };
--- a/frontend/src/components/Navbar.tsx
+++ b/frontend/src/components/Navbar.tsx
@@ -48,7 +48,7 @@ export function Navbar() {
        <div className="flex justify-between h-16">
          <div className="flex">
            <div className="flex-shrink-0 flex items-center">
-              <Clock className="h-8 w-8 text-primary-600" />
+              <img src="/icon.svg" alt="TimeTracker Logo" className="h-8 w-8 drop-shadow-sm" />
              <span className="ml-2 text-xl font-bold text-gray-900">
                TimeTracker
              </span>
--- a/frontend/src/components/TimeEntryFormModal.tsx
+++ b/frontend/src/components/TimeEntryFormModal.tsx
@@ -20,6 +20,7 @@ export function TimeEntryFormModal({ entry, onClose, createTimeEntry, updateTime
      return {
        startTime: getLocalISOString(new Date(entry.startTime)),
        endTime: getLocalISOString(new Date(entry.endTime)),
+        breakMinutes: entry.breakMinutes,
        description: entry.description || '',
        projectId: entry.projectId,
      };
@@ -29,6 +30,7 @@ export function TimeEntryFormModal({ entry, onClose, createTimeEntry, updateTime
    return {
      startTime: getLocalISOString(oneHourAgo),
      endTime: getLocalISOString(now),
+      breakMinutes: 0,
      description: '',
      projectId: projects?.[0]?.id || '',
    };
@@ -97,6 +99,16 @@ export function TimeEntryFormModal({ entry, onClose, createTimeEntry, updateTime
            />
          </div>
        </div>
+        <div>
+          <label className="label">Break (minutes)</label>
+          <input
+            type="number"
+            min="0"
+            value={formData.breakMinutes ?? 0}
+            onChange={(e) => setFormData({ ...formData, breakMinutes: parseInt(e.target.value) || 0 })}
+            className="input"
+          />
+        </div>
        <div>
          <label className="label">Description</label>
          <textarea
--- a/frontend/src/components/TimerWidget.tsx
+++ b/frontend/src/components/TimerWidget.tsx
@@ -1,5 +1,5 @@
-import { useState } from "react";
-import { Play, Square, ChevronDown } from "lucide-react";
+import { useState, useRef } from "react";
+import { Play, Square, ChevronDown, Pencil, Check, X, Trash2 } from "lucide-react";
 import { useTimer } from "@/contexts/TimerContext";
 import { useProjects } from "@/hooks/useProjects";
 import { ProjectColorDot } from "@/components/ProjectColorDot";
@@ -27,6 +27,21 @@ function TimerDisplay({ totalSeconds }: { totalSeconds: number }) {
  );
 }

+/** Converts a HH:mm string to an ISO datetime, inferring the correct date.
+ *  If the resulting time would be in the future, it is assumed to belong to the previous day.
+ */
+function timeInputToIso(timeValue: string): string {
+  const [hours, minutes] = timeValue.split(":").map(Number);
+  const now = new Date();
+  const candidate = new Date(now);
+  candidate.setHours(hours, minutes, 0, 0);
+  // If the candidate is in the future, roll back one day
+  if (candidate > now) {
+    candidate.setDate(candidate.getDate() - 1);
+  }
+  return candidate.toISOString();
+}
+
 export function TimerWidget() {
  const {
    ongoingTimer,
@@ -34,12 +49,19 @@ export function TimerWidget() {
    elapsedSeconds,
    startTimer,
    stopTimer,
+    cancelTimer,
    updateTimerProject,
+    updateTimerStartTime,
  } = useTimer();
  const { projects } = useProjects();
  const [showProjectSelect, setShowProjectSelect] = useState(false);
  const [error, setError] = useState<string | null>(null);

+  // Start time editing state
+  const [editingStartTime, setEditingStartTime] = useState(false);
+  const [startTimeInput, setStartTimeInput] = useState("");
+  const startTimeInputRef = useRef<HTMLInputElement>(null);
+
  const handleStart = async () => {
    setError(null);
    try {
@@ -58,6 +80,15 @@ export function TimerWidget() {
    }
  };

+  const handleCancelTimer = async () => {
+    setError(null);
+    try {
+      await cancelTimer();
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to cancel timer");
+    }
+  };
+
  const handleProjectChange = async (projectId: string) => {
    setError(null);
    try {
@@ -78,6 +109,42 @@ export function TimerWidget() {
    }
  };

+  const handleStartEditStartTime = () => {
+    if (!ongoingTimer) return;
+    const start = new Date(ongoingTimer.startTime);
+    const hh = start.getHours().toString().padStart(2, "0");
+    const mm = start.getMinutes().toString().padStart(2, "0");
+    setStartTimeInput(`${hh}:${mm}`);
+    setEditingStartTime(true);
+    // Focus the input on next render
+    setTimeout(() => startTimeInputRef.current?.focus(), 0);
+  };
+
+  const handleCancelEditStartTime = () => {
+    setEditingStartTime(false);
+    setError(null);
+  };
+
+  const handleConfirmStartTime = async () => {
+    if (!startTimeInput) return;
+    setError(null);
+    try {
+      const iso = timeInputToIso(startTimeInput);
+      await updateTimerStartTime(iso);
+      setEditingStartTime(false);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to update start time");
+    }
+  };
+
+  const handleStartTimeKeyDown = (e: React.KeyboardEvent<HTMLInputElement>) => {
+    if (e.key === "Enter") {
+      void handleConfirmStartTime();
+    } else if (e.key === "Escape") {
+      handleCancelEditStartTime();
+    }
+  };
+
  if (isLoading) {
    return (
      <div className="fixed bottom-0 left-0 right-0 bg-white border-t border-gray-200 py-4 shadow-lg">
@@ -95,20 +162,68 @@ export function TimerWidget() {
          <>
            {/* Row 1 (mobile): timer + stop side by side. On sm+ dissolves into the parent flex row via contents. */}
            <div className="flex items-center justify-between w-full sm:contents">
-              {/* Timer Display */}
+              {/* Timer Display + Start Time Editor */}
              <div className="flex items-center space-x-2 shrink-0">
                <div className="w-3 h-3 bg-red-500 rounded-full animate-pulse"></div>
-                <TimerDisplay totalSeconds={elapsedSeconds} />
+                {editingStartTime ? (
+                  <div className="flex items-center space-x-1">
+                    <span className="text-xs text-gray-500 mr-1">Started at</span>
+                    <input
+                      ref={startTimeInputRef}
+                      type="time"
+                      value={startTimeInput}
+                      onChange={(e) => setStartTimeInput(e.target.value)}
+                      onKeyDown={handleStartTimeKeyDown}
+                      className="font-mono text-lg font-bold text-gray-900 border border-primary-400 rounded px-2 py-0.5 focus:outline-none focus:ring-2 focus:ring-primary-500 w-28"
+                    />
+                    <button
+                      onClick={() => void handleConfirmStartTime()}
+                      title="Confirm"
+                      className="p-1 text-green-600 hover:text-green-700 hover:bg-green-50 rounded"
+                    >
+                      <Check className="h-4 w-4" />
+                    </button>
+                    <button
+                      onClick={handleCancelEditStartTime}
+                      title="Cancel"
+                      className="p-1 text-gray-400 hover:text-gray-600 hover:bg-gray-100 rounded"
+                    >
+                      <X className="h-4 w-4" />
+                    </button>
+                  </div>
+                ) : (
+                  <div className="flex items-center space-x-2">
+                    <TimerDisplay totalSeconds={elapsedSeconds} />
+                    <button
+                      onClick={handleStartEditStartTime}
+                      title="Adjust start time"
+                      className="p-1 text-gray-400 hover:text-gray-600 hover:bg-gray-100 rounded transition-colors"
+                    >
+                      <Pencil className="h-3.5 w-3.5" />
+                    </button>
+                  </div>
+                )}
              </div>

-              {/* Stop Button */}
-              <button
-                onClick={handleStop}
-                className="flex items-center space-x-2 px-6 py-3 bg-red-600 text-white rounded-lg font-medium hover:bg-red-700 transition-colors shrink-0 sm:order-last"
-              >
-                <Square className="h-5 w-5 fill-current" />
-                <span>Stop</span>
-              </button>
+              {/* Stop + Cancel Buttons */}
+              <div className="flex items-center space-x-2 shrink-0 sm:order-last">
+                <button
+                  onClick={() => void handleCancelTimer()}
+                  title="Discard timer"
+                  className="p-2 text-gray-400 hover:text-gray-600 hover:bg-gray-100 rounded-lg transition-colors"
+                >
+                  <Trash2 className="h-5 w-5" />
+                </button>
+                <button
+                  onClick={handleStop}
+                  disabled={!ongoingTimer.project}
+                  title={!ongoingTimer.project ? "Select a project to stop the timer" : undefined}
+                  className="flex items-center space-x-2 px-6 py-3 bg-red-600 text-white rounded-lg font-medium hover:bg-red-700 transition-colors disabled:opacity-40 disabled:cursor-not-allowed disabled:hover:bg-red-600"
+                >
+                  <Square className="h-5 w-5 fill-current" />
+                  <span>Stop</span>
+                </button>
+              </div>
            </div>

            {/* Project Selector — full width on mobile, auto on desktop */}
--- a/frontend/src/contexts/TimerContext.tsx
+++ b/frontend/src/contexts/TimerContext.tsx
@@ -17,6 +17,8 @@ interface TimerContextType {
  elapsedSeconds: number;
  startTimer: (projectId?: string) => Promise<void>;
  updateTimerProject: (projectId?: string | null) => Promise<void>;
+  updateTimerStartTime: (startTime: string) => Promise<void>;
+  cancelTimer: () => Promise<void>;
  stopTimer: (projectId?: string) => Promise<TimeEntry | null>;
 }

@@ -84,6 +86,14 @@ export function TimerProvider({ children }: { children: ReactNode }) {
    },
  });

+  // Cancel timer mutation
+  const cancelMutation = useMutation({
+    mutationFn: timerApi.cancel,
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ["ongoingTimer"] });
+    },
+  });
+
  // Stop timer mutation
  const stopMutation = useMutation({
    mutationFn: timerApi.stop,
@@ -102,11 +112,22 @@ export function TimerProvider({ children }: { children: ReactNode }) {

  const updateTimerProject = useCallback(
    async (projectId?: string | null) => {
-      await updateMutation.mutateAsync(projectId);
+      await updateMutation.mutateAsync({ projectId });
    },
    [updateMutation],
  );

+  const updateTimerStartTime = useCallback(
+    async (startTime: string) => {
+      await updateMutation.mutateAsync({ startTime });
+    },
+    [updateMutation],
+  );
+
+  const cancelTimer = useCallback(async () => {
+    await cancelMutation.mutateAsync();
+  }, [cancelMutation]);
+
  const stopTimer = useCallback(
    async (projectId?: string): Promise<TimeEntry | null> => {
      try {
@@ -127,6 +148,8 @@ export function TimerProvider({ children }: { children: ReactNode }) {
        elapsedSeconds,
        startTimer,
        updateTimerProject,
+        updateTimerStartTime,
+        cancelTimer,
        stopTimer,
      }}
    >
--- a/frontend/src/pages/DashboardPage.tsx
+++ b/frontend/src/pages/DashboardPage.tsx
@@ -56,7 +56,7 @@ export function DashboardPage() {

  const totalTodaySeconds =
    todayEntries?.entries.reduce((total, entry) => {
-      return total + calculateDuration(entry.startTime, entry.endTime);
+      return total + calculateDuration(entry.startTime, entry.endTime, entry.breakMinutes);
    }, 0) || 0;

  const targetsWithData = targets?.filter(t => t.weeks.length > 0) ?? [];
@@ -216,7 +216,10 @@ export function DashboardPage() {
                      <div className="text-xs text-gray-400">{formatTime(entry.startTime)} – {formatTime(entry.endTime)}</div>
                    </td>
                    <td className="px-4 py-3 whitespace-nowrap text-sm text-gray-900 font-mono">
-                      {formatDurationFromDatesHoursMinutes(entry.startTime, entry.endTime)}
+                      {formatDurationFromDatesHoursMinutes(entry.startTime, entry.endTime, entry.breakMinutes)}
+                      {entry.breakMinutes > 0 && (
+                        <span className="text-xs text-gray-400 ml-1">(−{entry.breakMinutes}m break)</span>
+                      )}
                    </td>
                    <td className="px-4 py-3 whitespace-nowrap text-right">
                      <button onClick={() => handleOpenModal(entry)} className="p-1.5 text-gray-400 hover:text-gray-600 mr-1"><Edit2 className="h-4 w-4" /></button>
--- a/frontend/src/pages/LoginPage.tsx
+++ b/frontend/src/pages/LoginPage.tsx
@@ -1,4 +1,3 @@
-import { Clock } from 'lucide-react';
 import { useAuth } from '@/contexts/AuthContext';

 export function LoginPage() {
@@ -8,8 +7,8 @@ export function LoginPage() {
    <div className="min-h-screen flex items-center justify-center bg-gray-50">
      <div className="max-w-md w-full space-y-8 p-8">
        <div className="text-center">
-          <div className="mx-auto h-16 w-16 bg-primary-100 rounded-full flex items-center justify-center">
-            <Clock className="h-8 w-8 text-primary-600" />
+          <div className="mx-auto h-16 w-16 flex items-center justify-center drop-shadow-sm">
+            <img src="/icon.svg" alt="TimeTracker Logo" className="h-16 w-16" />
          </div>
          <h2 className="mt-6 text-3xl font-bold text-gray-900">TimeTracker</h2>
          <p className="mt-2 text-sm text-gray-600">
--- a/frontend/src/pages/TimeEntriesPage.tsx
+++ b/frontend/src/pages/TimeEntriesPage.tsx
@@ -78,7 +78,10 @@ export function TimeEntriesPage() {
                  </div>
                </td>
                <td className="px-4 py-3 whitespace-nowrap text-sm font-mono text-gray-900">
-                  {formatDurationFromDatesHoursMinutes(entry.startTime, entry.endTime)}
+                  {formatDurationFromDatesHoursMinutes(entry.startTime, entry.endTime, entry.breakMinutes)}
+                  {entry.breakMinutes > 0 && (
+                    <span className="text-xs text-gray-400 ml-1">(−{entry.breakMinutes}m)</span>
+                  )}
                </td>
                <td className="px-4 py-3 whitespace-nowrap text-right">
                  <button onClick={() => handleOpenModal(entry)} className="p-1.5 text-gray-400 hover:text-gray-600 mr-1"><Edit2 className="h-4 w-4" /></button>
--- a/frontend/src/types/index.ts
+++ b/frontend/src/types/index.ts
@@ -28,6 +28,7 @@ export interface TimeEntry {
  id: string;
  startTime: string;
  endTime: string;
+  breakMinutes: number;
  description: string | null;
  projectId: string;
  project: Pick<Project, 'id' | 'name' | 'color'> & {
@@ -129,6 +130,7 @@ export interface UpdateProjectInput {
 export interface CreateTimeEntryInput {
  startTime: string;
  endTime: string;
+  breakMinutes?: number;
  description?: string;
  projectId: string;
 }
@@ -136,6 +138,7 @@ export interface CreateTimeEntryInput {
 export interface UpdateTimeEntryInput {
  startTime?: string;
  endTime?: string;
+  breakMinutes?: number;
  description?: string;
  projectId?: string;
 }
--- a/frontend/src/utils/dateUtils.ts
+++ b/frontend/src/utils/dateUtils.ts
@@ -43,7 +43,14 @@ export function formatDurationHoursMinutes(totalSeconds: number): string {
  return `${hours}h ${minutes}m`;
 }

-export function calculateDuration(startTime: string, endTime: string): number {
+export function calculateDuration(startTime: string, endTime: string, breakMinutes: number = 0): number {
+  const start = parseISO(startTime);
+  const end = parseISO(endTime);
+  const totalSeconds = differenceInSeconds(end, start);
+  return totalSeconds - (breakMinutes * 60);
+}
+
+export function calculateGrossDuration(startTime: string, endTime: string): number {
  const start = parseISO(startTime);
  const end = parseISO(endTime);
  return differenceInSeconds(end, start);
@@ -52,16 +59,18 @@ export function calculateDuration(startTime: string, endTime: string): number {
 export function formatDurationFromDates(
  startTime: string,
  endTime: string,
+  breakMinutes: number = 0,
 ): string {
-  const seconds = calculateDuration(startTime, endTime);
+  const seconds = calculateDuration(startTime, endTime, breakMinutes);
  return formatDuration(seconds);
 }

 export function formatDurationFromDatesHoursMinutes(
  startTime: string,
  endTime: string,
+  breakMinutes: number = 0,
 ): string {
-  const seconds = calculateDuration(startTime, endTime);
+  const seconds = calculateDuration(startTime, endTime, breakMinutes);
  return formatDurationHoursMinutes(seconds);
 }