diff --git a/src/lib/schemas.ts b/src/lib/schemas.ts
new file mode 100644
index 0000000..9d06011
--- /dev/null
+++ b/src/lib/schemas.ts
@@ -0,0 +1,61 @@
+import { z } from "zod";
+
+export const checklistItemSchema = z.object({
+  id: z.string(),
+  text: z.string(),
+  checked: z.boolean(),
+});
+
+export const attachmentSchema = z.object({
+  id: z.string(),
+  name: z.string(),
+  path: z.string(),
+  mode: z.enum(["link", "copy"]).default("link"),
+});
+
+export const labelSchema = z.object({
+  id: z.string(),
+  name: z.string(),
+  color: z.string(),
+});
+
+export const cardSchema = z.object({
+  id: z.string(),
+  title: z.string(),
+  description: z.string().default(""),
+  labels: z.array(z.string()).default([]),
+  checklist: z.array(checklistItemSchema).default([]),
+  dueDate: z.string().nullable().default(null),
+  attachments: z.array(attachmentSchema).default([]),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export const columnSchema = z.object({
+  id: z.string(),
+  title: z.string(),
+  cardIds: z.array(z.string()).default([]),
+  width: z.enum(["narrow", "standard", "wide"]).default("standard"),
+});
+
+export const boardSettingsSchema = z.object({
+  attachmentMode: z.enum(["link", "copy"]).default("link"),
+});
+
+export const boardSchema = z.object({
+  id: z.string(),
+  title: z.string(),
+  color: z.string().default("#6366f1"),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+  columns: z.array(columnSchema).default([]),
+  cards: z.record(z.string(), cardSchema).default({}),
+  labels: z.array(labelSchema).default([]),
+  settings: boardSettingsSchema.default({ attachmentMode: "link" }),
+});
+
+export const appSettingsSchema = z.object({
+  theme: z.enum(["light", "dark", "system"]).default("system"),
+  dataDirectory: z.string().nullable().default(null),
+  recentBoardIds: z.array(z.string()).default([]),
+});
diff --git a/src/types/board.ts b/src/types/board.ts
new file mode 100644
index 0000000..9b62eaf
--- /dev/null
+++ b/src/types/board.ts
@@ -0,0 +1,64 @@
+export interface Board {
+  id: string;
+  title: string;
+  color: string;
+  createdAt: string;
+  updatedAt: string;
+  columns: Column[];
+  cards: Record<string, Card>;
+  labels: Label[];
+  settings: BoardSettings;
+}
+
+export interface Column {
+  id: string;
+  title: string;
+  cardIds: string[];
+  width: ColumnWidth;
+}
+
+export type ColumnWidth = "narrow" | "standard" | "wide";
+
+export interface Card {
+  id: string;
+  title: string;
+  description: string;
+  labels: string[];
+  checklist: ChecklistItem[];
+  dueDate: string | null;
+  attachments: Attachment[];
+  createdAt: string;
+  updatedAt: string;
+}
+
+export interface Label {
+  id: string;
+  name: string;
+  color: string;
+}
+
+export interface ChecklistItem {
+  id: string;
+  text: string;
+  checked: boolean;
+}
+
+export interface Attachment {
+  id: string;
+  name: string;
+  path: string;
+  mode: "link" | "copy";
+}
+
+export interface BoardSettings {
+  attachmentMode: "link" | "copy";
+}
+
+export interface BoardMeta {
+  id: string;
+  title: string;
+  color: string;
+  cardCount: number;
+  columnCount: number;
+  updatedAt: string;
+}
diff --git a/src/types/settings.ts b/src/types/settings.ts
new file mode 100644
index 0000000..df9d675
--- /dev/null
+++ b/src/types/settings.ts
@@ -0,0 +1,5 @@
+export interface AppSettings {
+  theme: "light" | "dark" | "system";
+  dataDirectory: string | null;
+  recentBoardIds: string[];
+}