diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 960f15ac8..9217b9d1d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -30,8 +30,8 @@ jobs:
           cache: npm
           cache-dependency-path: harvest-finance/backend/package-lock.json
 
-      - run: npm ci || true
-      - run: npm run lint || true
+      - run: npm ci
+      - run: npm run lint
 
   backend-test:
     name: Backend — Unit + Integration Tests
@@ -88,7 +88,7 @@ jobs:
 
       - run: npm ci
       - run: npm run build
-      - run: npm test -- --forceExit --passWithNoTests || true
+      - run: npm run test:cov -- --forceExit
       - name: Upload coverage
         uses: actions/upload-artifact@v4
         if: always()
@@ -149,7 +149,7 @@ jobs:
           cache-dependency-path: harvest-finance/frontend/package-lock.json
 
       - run: npm ci
-      - run: npm test -- --passWithNoTests
+      - run: npm run test:cov -- --passWithNoTests
       - run: npm run test:vitest -- --run --passWithNoTests
 
   frontend-build:
@@ -171,7 +171,7 @@ jobs:
           cache: npm
           cache-dependency-path: harvest-finance/frontend/package-lock.json
 
-      - run: npm ci || true
+      - run: npm ci
       - run: npm run build
       - name: Route-level bundle budget
         run: npm run check:budget
@@ -207,11 +207,11 @@ jobs:
 
       - name: Run forge tests
         working-directory: contracts
-        run: forge test -vvv || true
+        run: forge test -vvv
 
       - name: Forge coverage
         working-directory: contracts
-        run: forge coverage --report lcov || true
+        run: forge coverage --report lcov
 
       - name: Upload coverage
         uses: actions/upload-artifact@v4
diff --git a/harvest-finance/backend/package.json b/harvest-finance/backend/package.json
index 49fb09865..d6fea2fa1 100644
--- a/harvest-finance/backend/package.json
+++ b/harvest-finance/backend/package.json
@@ -144,6 +144,14 @@
       "**/*.(t|j)s"
     ],
     "coverageDirectory": "../coverage",
-    "testEnvironment": "node"
+    "testEnvironment": "node",
+    "coverageThreshold": {
+      "global": {
+        "branches": 80,
+        "functions": 80,
+        "lines": 80,
+        "statements": 80
+      }
+    }
   }
 }
diff --git a/harvest-finance/backend/src/common/sanitization/input-sanitizer.service.spec.ts b/harvest-finance/backend/src/common/sanitization/input-sanitizer.service.spec.ts
index 22ae7265a..ea8fbb29d 100644
--- a/harvest-finance/backend/src/common/sanitization/input-sanitizer.service.spec.ts
+++ b/harvest-finance/backend/src/common/sanitization/input-sanitizer.service.spec.ts
@@ -98,6 +98,24 @@ describe('InputSanitizerService', () => {
       ).toBe(validStellarPublicKey);
     });
 
+    it.each(['', '   ', 'G' + 'A'.repeat(55), validStellarPublicKey.slice(0, -1)])(
+      'rejects invalid public key "%s"',
+      (value) => {
+        expect(() => service.validateStellarPublicKey(value)).toThrow(
+          BadRequestException,
+        );
+      },
+    );
+
+    it.each([null, undefined, 42, {}, []])(
+      'rejects non-string public key value %p',
+      (value) => {
+        expect(() =>
+          service.validateStellarPublicKey(value as unknown as string),
+        ).toThrow(BadRequestException);
+      },
+    );
+
     it('rejects malformed Stellar public keys with format guidance', () => {
       expect(() => service.validateStellarPublicKey('invalid')).toThrow(
         /G-address with a correct Stellar StrKey checksum/,
@@ -173,18 +191,88 @@ describe('InputSanitizerService', () => {
   });
 
   describe('validateAmount', () => {
+    it.each([
+      [0, 0],
+      [100.5, 100.5],
+      ['25.25', 25.25],
+    ])('accepts amount %p and returns %p', (input, expected) => {
+      expect(service.validateAmount(input)).toBe(expected);
+    });
+
+    it.each([
+      [-0.01, 0, 100],
+      [100.01, 0, 100],
+      [10, 11, 20],
+      [10, 0, 9],
+    ])('rejects amount %p outside [%p, %p]', (input, min, max) => {
+      expect(() => service.validateAmount(input, min, max)).toThrow(
+        BadRequestException,
+      );
+    });
+
     it('rejects non-finite amounts with bounds guidance', () => {
       expect(() => service.validateAmount(Number.POSITIVE_INFINITY)).toThrow(
         /finite numeric value/,
       );
     });
+
+    it.each([NaN, Number.NEGATIVE_INFINITY, 'not-a-number', {}])(
+      'rejects non-numeric amount %p',
+      (value) => {
+        expect(() => service.validateAmount(value)).toThrow(BadRequestException);
+      },
+    );
   });
 
   describe('sanitizeString', () => {
+    it('trims surrounding whitespace and removes null bytes', () => {
+      expect(service.sanitizeString('  hello\0 world  ')).toBe('hello world');
+    });
+
+    it('accepts a value exactly at the maximum length', () => {
+      expect(service.sanitizeString('a'.repeat(3), 3)).toBe('aaa');
+    });
+
     it('rejects oversized strings with max length guidance', () => {
       expect(() => service.sanitizeString('abcd', 3)).toThrow(
         /3 characters or fewer/,
       );
     });
+
+    it.each([null, undefined, 123, {}, []])(
+      'rejects non-string input %p',
+      (value) => {
+        expect(() => service.sanitizeString(value as unknown as string)).toThrow(
+          BadRequestException,
+        );
+      },
+    );
+  });
+
+  describe('validatePagination', () => {
+    it('uses safe defaults when parameters are omitted', () => {
+      expect(service.validatePagination()).toEqual({ skip: 0, limit: 20 });
+    });
+
+    it('floors values and clamps skip and limit to safe bounds', () => {
+      expect(service.validatePagination(4.9, 8.9, 10)).toEqual({
+        skip: 4,
+        limit: 8,
+      });
+      expect(service.validatePagination(-3, 0, 10)).toEqual({
+        skip: 0,
+        limit: 1,
+      });
+      expect(service.validatePagination(2, 100, 10)).toEqual({
+        skip: 2,
+        limit: 10,
+      });
+    });
+
+    it('handles invalid numeric values using defaults', () => {
+      expect(service.validatePagination(NaN, NaN)).toEqual({
+        skip: 0,
+        limit: 20,
+      });
   });
 });
diff --git a/harvest-finance/frontend/jest.config.js b/harvest-finance/frontend/jest.config.js
index 8111f1390..0082b004d 100644
--- a/harvest-finance/frontend/jest.config.js
+++ b/harvest-finance/frontend/jest.config.js
@@ -13,6 +13,15 @@ const config = {
   moduleNameMapper: {
     '^@/(.*)$': '<rootDir>/src/$1',
   },
+  collectCoverageFrom: ['src/**/*.{ts,tsx}', '!src/**/*.d.ts'],
+  coverageThreshold: {
+    global: {
+      branches: 80,
+      functions: 80,
+      lines: 80,
+      statements: 80,
+    },
+  },
 };
 
 module.exports = createJestConfig(config);
diff --git a/harvest-finance/frontend/src/app/login/login-page.test.tsx b/harvest-finance/frontend/src/app/login/login-page.test.tsx
new file mode 100644
index 000000000..709e1ea29
--- /dev/null
+++ b/harvest-finance/frontend/src/app/login/login-page.test.tsx
@@ -0,0 +1,50 @@
+import React from 'react';
+import { fireEvent, render, screen, waitFor } from '@testing-library/react';
+import LoginPage from './page';
+import { useAuthStore } from '@/lib/stores/auth-store';
+
+jest.mock('@/lib/stores/auth-store');
+jest.mock('next/navigation', () => ({ useRouter: () => ({ push: jest.fn() }) }));
+jest.mock('next-intl', () => ({ useTranslations: () => (key: string) => key }));
+
+const mockedAuthStore = useAuthStore as jest.MockedFunction<typeof useAuthStore>;
+
+describe('LoginPage', () => {
+  it('shows validation errors and submits valid credentials', async () => {
+    const login = jest.fn().mockResolvedValue(undefined);
+    mockedAuthStore.mockReturnValue({
+      login,
+      isLoading: false,
+      error: null,
+      clearError: jest.fn(),
+      isAuthenticated: false,
+      hydrate: jest.fn(),
+    } as any);
+    render(<LoginPage />);
+
+    fireEvent.click(screen.getByRole('button', { name: 'Sign in' }));
+    expect(await screen.findByText('Please enter a valid email address')).toBeInTheDocument();
+
+    fireEvent.change(screen.getByLabelText('Email address'), { target: { value: 'farmer@example.com' } });
+    fireEvent.change(screen.getByLabelText('Password'), { target: { value: 'secret' } });
+    fireEvent.click(screen.getByRole('button', { name: 'Sign in' }));
+    await waitFor(() => expect(login).toHaveBeenCalledWith('farmer@example.com', 'secret'));
+  });
+
+  it('renders store errors and toggles password visibility', () => {
+    mockedAuthStore.mockReturnValue({
+      login: jest.fn(),
+      isLoading: false,
+      error: 'Invalid credentials',
+      clearError: jest.fn(),
+      isAuthenticated: false,
+      hydrate: jest.fn(),
+    } as any);
+    render(<LoginPage />);
+
+    expect(screen.getByRole('alert')).toHaveTextContent('Invalid credentials');
+    const password = screen.getByLabelText('Password');
+    fireEvent.click(screen.getByRole('button', { name: 'Show password' }));
+    expect(password).toHaveAttribute('type', 'text');
+  });
+});
\ No newline at end of file
diff --git a/harvest-finance/frontend/src/components/dashboard/dashboard-components.test.tsx b/harvest-finance/frontend/src/components/dashboard/dashboard-components.test.tsx
new file mode 100644
index 000000000..e2b2c8a46
--- /dev/null
+++ b/harvest-finance/frontend/src/components/dashboard/dashboard-components.test.tsx
@@ -0,0 +1,67 @@
+import React from 'react';
+import { fireEvent, render, screen, waitFor } from '@testing-library/react';
+import { VaultTable } from './VaultTable';
+import { YieldChart } from '../YieldChart';
+import { vaultApi } from '@/lib/api/vault-client';
+
+jest.mock('@/lib/i18n', () => ({
+  useTranslation: () => ({ t: (key: string) => key }),
+}));
+
+jest.mock('recharts', () => ({
+  ResponsiveContainer: ({ children }: { children: React.ReactNode }) => <div>{children}</div>,
+  AreaChart: ({ children }: { children: React.ReactNode }) => <div role="img" aria-label="APY chart">{children}</div>,
+  LineChart: ({ children }: { children: React.ReactNode }) => <div role="img" aria-label="APY chart">{children}</div>,
+  Area: () => null,
+  Line: () => null,
+  XAxis: () => null,
+  YAxis: () => null,
+  CartesianGrid: () => null,
+  Tooltip: () => null,
+}));
+
+jest.mock('@/lib/api/vault-client', () => ({
+  vaultApi: { getApyHistory: jest.fn() },
+}));
+
+const vaults = [
+  { id: 'low', name: 'Low Risk', asset: 'USDC', apy: 4, tvl: 100, riskLevel: 'Low' as const, balance: '0', walletBalance: '50', seasonalTarget: 10 },
+  { id: 'high', name: 'High Yield', asset: 'XLM', apy: 9, tvl: 200, riskLevel: 'High' as const, balance: '0', walletBalance: '50', seasonalTarget: 10 },
+];
+
+describe('VaultTable', () => {
+  it('sorts vaults and routes deposit and withdrawal actions', () => {
+    const onDeposit = jest.fn();
+    const onWithdraw = jest.fn();
+    render(<VaultTable vaults={vaults} onDeposit={onDeposit} onWithdraw={onWithdraw} />);
+
+    expect(screen.getByText('High Yield')).toBeInTheDocument();
+    fireEvent.click(screen.getByText('dashboard.vault_name'));
+    expect(screen.getAllByRole('row')[1]).toHaveTextContent('High Yield');
+
+    fireEvent.click(screen.getAllByRole('button', { name: 'common.deposit' })[0]);
+    fireEvent.click(screen.getAllByRole('button', { name: 'common.withdraw' })[0]);
+    expect(onDeposit).toHaveBeenCalledWith('high');
+    expect(onWithdraw).toHaveBeenCalledWith('high');
+  });
+
+  it('renders an empty state', () => {
+    render(<VaultTable vaults={[]} onDeposit={jest.fn()} onWithdraw={jest.fn()} />);
+    expect(screen.getByText('dashboard.no_vaults_found')).toBeInTheDocument();
+  });
+});
+
+describe('YieldChart', () => {
+  it('renders loading, data, and API error states', async () => {
+    const getApyHistory = vaultApi.getApyHistory as jest.Mock;
+    getApyHistory.mockResolvedValueOnce([{ date: '2026-01-01', apy: 7.25 }]);
+    const { rerender } = render(<YieldChart vaultId="vault-1" />);
+    expect(document.querySelector('.animate-spin')).toBeInTheDocument();
+    await waitFor(() => expect(screen.getByRole('img', { name: 'APY chart' })).toBeInTheDocument());
+
+    getApyHistory.mockRejectedValueOnce(new Error('RPC unavailable'));
+    rerender(<YieldChart vaultId="vault-2" />);
+    await waitFor(() => expect(screen.getByText('RPC unavailable')).toBeInTheDocument());
+    expect(screen.getByRole('button', { name: 'Retry' })).toBeInTheDocument();
+  });
+});
\ No newline at end of file
diff --git a/harvest-finance/frontend/src/components/ui/ui-components.test.tsx b/harvest-finance/frontend/src/components/ui/ui-components.test.tsx
new file mode 100644
index 000000000..18ba2fcc1
--- /dev/null
+++ b/harvest-finance/frontend/src/components/ui/ui-components.test.tsx
@@ -0,0 +1,51 @@
+import React from 'react';
+import { fireEvent, render, screen } from '@testing-library/react';
+import { Button } from './Button';
+import { Modal, ModalBody, ModalHeader } from './Modal';
+
+describe('Button', () => {
+  it('renders content, forwards type, and invokes its handler', () => {
+    const onClick = jest.fn();
+    render(
+      <Button type="submit" leftIcon={<span aria-hidden="true">+</span>} onClick={onClick}>
+        Save
+      </Button>,
+    );
+
+    fireEvent.click(screen.getByRole('button', { name: 'Save' }));
+    expect(onClick).toHaveBeenCalledTimes(1);
+    expect(screen.getByRole('button')).toHaveAttribute('type', 'submit');
+  });
+
+  it('disables the button and exposes busy state while loading', () => {
+    render(<Button isLoading>Saving</Button>);
+
+    expect(screen.getByRole('button')).toBeDisabled();
+    expect(screen.getByRole('button')).toHaveAttribute('aria-busy', 'true');
+    expect(screen.getByText('Saving')).toBeInTheDocument();
+  });
+});
+
+describe('Modal', () => {
+  it('renders nothing when closed and supports close button and Escape', () => {
+    const onClose = jest.fn();
+    const { rerender } = render(
+      <Modal isOpen={false} onClose={onClose}>
+        Hidden
+      </Modal>,
+    );
+    expect(screen.queryByRole('dialog')).not.toBeInTheDocument();
+
+    rerender(
+      <Modal isOpen onClose={onClose}>
+        <ModalHeader title="Confirm" />
+        <ModalBody>Visible content</ModalBody>
+      </Modal>,
+    );
+
+    expect(screen.getByRole('dialog')).toHaveAttribute('aria-modal', 'true');
+    expect(screen.getByText('Visible content')).toBeInTheDocument();
+    fireEvent.keyDown(document, { key: 'Escape' });
+    expect(onClose).toHaveBeenCalledTimes(1);
+  });
+});
\ No newline at end of file