diff --git a/frontends/nextjs/src/lib/db/packages/get-installed-packages.test.ts b/frontends/nextjs/src/lib/db/packages/get-installed-packages.test.ts
new file mode 100644
index 000000000..3bdd4d153
--- /dev/null
+++ b/frontends/nextjs/src/lib/db/packages/get-installed-packages.test.ts
@@ -0,0 +1,33 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+const mockList = vi.fn()
+const mockAdapter = { list: mockList }
+
+vi.mock('../dbal-client', () => ({
+  getAdapter: () => mockAdapter,
+}))
+
+import { getInstalledPackages } from './get-installed-packages'
+
+describe('getInstalledPackages', () => {
+  beforeEach(() => {
+    mockList.mockReset()
+  })
+
+  it('returns mapped installed packages', async () => {
+    mockList.mockResolvedValue({
+      data: [
+        { packageId: 'pkg_one', installedAt: BigInt(100), version: '1.0.0', enabled: true },
+        { packageId: 'pkg_two', installedAt: BigInt(200), version: '2.0.0', enabled: false },
+      ],
+    })
+
+    const result = await getInstalledPackages()
+
+    expect(mockList).toHaveBeenCalledWith('InstalledPackage')
+    expect(result).toEqual([
+      { packageId: 'pkg_one', installedAt: 100, version: '1.0.0', enabled: true },
+      { packageId: 'pkg_two', installedAt: 200, version: '2.0.0', enabled: false },
+    ])
+  })
+})
diff --git a/frontends/nextjs/src/lib/db/packages/install-package.test.ts b/frontends/nextjs/src/lib/db/packages/install-package.test.ts
new file mode 100644
index 000000000..93f1dcbbb
--- /dev/null
+++ b/frontends/nextjs/src/lib/db/packages/install-package.test.ts
@@ -0,0 +1,52 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+
+const mockFindFirst = vi.fn()
+const mockCreate = vi.fn()
+const mockAdapter = { findFirst: mockFindFirst, create: mockCreate }
+
+vi.mock('../dbal-client', () => ({
+  getAdapter: () => mockAdapter,
+}))
+
+import { installPackage } from './install-package'
+
+describe('installPackage', () => {
+  beforeEach(() => {
+    mockFindFirst.mockReset()
+    mockCreate.mockReset()
+  })
+
+  it('creates package when not installed', async () => {
+    mockFindFirst.mockResolvedValue(null)
+
+    await installPackage({
+      packageId: 'pkg_one',
+      installedAt: 1234,
+      version: '1.2.3',
+      enabled: true,
+    })
+
+    expect(mockFindFirst).toHaveBeenCalledWith('InstalledPackage', {
+      where: { packageId: 'pkg_one' },
+    })
+    expect(mockCreate).toHaveBeenCalledWith('InstalledPackage', {
+      packageId: 'pkg_one',
+      installedAt: BigInt(1234),
+      version: '1.2.3',
+      enabled: true,
+    })
+  })
+
+  it('does not create when already installed', async () => {
+    mockFindFirst.mockResolvedValue({ packageId: 'pkg_one' })
+
+    await installPackage({
+      packageId: 'pkg_one',
+      installedAt: 1234,
+      version: '1.2.3',
+      enabled: true,
+    })
+
+    expect(mockCreate).not.toHaveBeenCalled()
+  })
+})
diff --git a/frontends/nextjs/src/lib/nerd-mode-ide/append-node.ts b/frontends/nextjs/src/lib/nerd-mode-ide/append-node.ts
new file mode 100644
index 000000000..f6ac704ed
--- /dev/null
+++ b/frontends/nextjs/src/lib/nerd-mode-ide/append-node.ts
@@ -0,0 +1,16 @@
+import type { FileNode } from './types'
+
+export function appendNode(nodes: FileNode[], parentId: string | null, newNode: FileNode): FileNode[] {
+  if (!parentId) return [...nodes, newNode]
+
+  return nodes.map((node) => {
+    if (node.id === parentId && node.type === 'folder') {
+      const children = node.children ? [...node.children, newNode] : [newNode]
+      return { ...node, children, expanded: true }
+    }
+    if (node.children) {
+      return { ...node, children: appendNode(node.children, parentId, newNode) }
+    }
+    return node
+  })
+}
diff --git a/frontends/nextjs/src/lib/nerd-mode-ide/create-file-node.ts b/frontends/nextjs/src/lib/nerd-mode-ide/create-file-node.ts
new file mode 100644
index 000000000..bc67c7cef
--- /dev/null
+++ b/frontends/nextjs/src/lib/nerd-mode-ide/create-file-node.ts
@@ -0,0 +1,20 @@
+import { createNodeId } from './create-node-id'
+import { getLanguageFromFilename } from './get-language-from-filename'
+import type { FileNode } from './types'
+
+interface CreateFileNodeOptions {
+  name: string
+  content?: string
+  exportPath?: string
+}
+
+export function createFileNode({ name, content = '', exportPath }: CreateFileNodeOptions): FileNode {
+  return {
+    id: createNodeId('file'),
+    name,
+    type: 'file',
+    content,
+    language: getLanguageFromFilename(name),
+    exportPath,
+  }
+}
diff --git a/frontends/nextjs/src/lib/nerd-mode-ide/create-folder-node.ts b/frontends/nextjs/src/lib/nerd-mode-ide/create-folder-node.ts
new file mode 100644
index 000000000..42b0b11b3
--- /dev/null
+++ b/frontends/nextjs/src/lib/nerd-mode-ide/create-folder-node.ts
@@ -0,0 +1,20 @@
+import { createNodeId } from './create-node-id'
+import type { FileNode } from './types'
+
+interface CreateFolderNodeOptions {
+  name: string
+  children?: FileNode[]
+  expanded?: boolean
+  exportPath?: string
+}
+
+export function createFolderNode({ name, children = [], expanded = false, exportPath }: CreateFolderNodeOptions): FileNode {
+  return {
+    id: createNodeId('folder'),
+    name,
+    type: 'folder',
+    children,
+    expanded,
+    exportPath,
+  }
+}