diff --git a/packages/backend/server/src/models/__tests__/blob.spec.ts b/packages/backend/server/src/models/__tests__/blob.spec.ts
new file mode 100644
index 000000000..98156d966
--- /dev/null
+++ b/packages/backend/server/src/models/__tests__/blob.spec.ts
@@ -0,0 +1,173 @@
+import test from 'ava';
+
+import { createModule } from '../../__tests__/create-module';
+import { Mockers } from '../../__tests__/mocks';
+import { Models } from '..';
+
+const module = await createModule();
+const models = module.get(Models);
+
+test.after.always(async () => {
+  await module.close();
+});
+
+test('should upsert blob', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+
+  // add
+  const blob = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  t.is(blob.workspaceId, workspace.id);
+  t.is(blob.key, 'test-key');
+  t.is(blob.mime, 'text/plain');
+  t.is(blob.size, 100);
+  t.is(blob.deletedAt, null);
+  t.truthy(blob.createdAt);
+
+  // update
+  const blob2 = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/html',
+    size: 200,
+  });
+
+  t.is(blob2.workspaceId, workspace.id);
+  t.is(blob2.key, 'test-key');
+  t.is(blob2.mime, 'text/html');
+  t.is(blob2.size, 200);
+  t.is(blob2.deletedAt, null);
+
+  // make sure only one blob is created
+  const blobs = await models.blob.list(workspace.id);
+  t.is(blobs.length, 1);
+  t.deepEqual(blobs[0], blob2);
+});
+
+test('should delete blob', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+  const blob = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  await models.blob.delete(workspace.id, blob.key);
+
+  const blob2 = await models.blob.get(workspace.id, blob.key);
+
+  t.truthy(blob2);
+  t.truthy(blob2?.deletedAt);
+});
+
+test('should delete blob permanently', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+  const blob = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  await models.blob.delete(workspace.id, blob.key, true);
+
+  const blob2 = await models.blob.get(workspace.id, blob.key);
+  t.is(blob2, null);
+});
+
+test('should list blobs', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+  const blob1 = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  const blob2 = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key2',
+    mime: 'text/plain',
+    size: 200,
+  });
+
+  const blobs = await models.blob.list(workspace.id);
+
+  t.is(blobs.length, 2);
+  blobs.sort((a, b) => a.key.localeCompare(b.key));
+  t.is(blobs[0].key, blob1.key);
+  t.is(blobs[1].key, blob2.key);
+});
+
+test('should list deleted blobs', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+  const blob = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  await models.blob.delete(workspace.id, blob.key);
+
+  const blobs = await models.blob.listDeleted(workspace.id);
+
+  t.is(blobs.length, 1);
+  t.is(blobs[0].key, blob.key);
+  t.truthy(blobs[0].deletedAt);
+
+  // delete permanently
+  await models.blob.delete(workspace.id, blob.key, true);
+
+  const blobs2 = await models.blob.listDeleted(workspace.id);
+
+  t.is(blobs2.length, 0);
+});
+
+test('should get blob', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+  const blob = await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  const blob2 = await models.blob.get(workspace.id, blob.key);
+
+  t.truthy(blob2);
+  t.is(blob2?.key, blob.key);
+});
+
+test('should total blob size in workspace', async t => {
+  const workspace = await module.create(Mockers.Workspace);
+
+  // default size is 0
+  const size1 = await models.blob.totalSize(workspace.id);
+
+  t.is(size1, 0);
+
+  await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key',
+    mime: 'text/plain',
+    size: 100,
+  });
+
+  await models.blob.upsert({
+    workspaceId: workspace.id,
+    key: 'test-key2',
+    mime: 'text/plain',
+    size: 200,
+  });
+
+  const size2 = await models.blob.totalSize(workspace.id);
+
+  t.is(size2, 300);
+});
diff --git a/packages/backend/server/src/models/blob.ts b/packages/backend/server/src/models/blob.ts
new file mode 100644
index 000000000..65f88d124
--- /dev/null
+++ b/packages/backend/server/src/models/blob.ts
@@ -0,0 +1,101 @@
+import { Injectable } from '@nestjs/common';
+import { Prisma } from '@prisma/client';
+
+import { BaseModel } from './base';
+
+export type CreateBlobInput = Prisma.BlobUncheckedCreateInput;
+
+/**
+ * Blob Model
+ */
+@Injectable()
+export class BlobModel extends BaseModel {
+  async upsert(blob: CreateBlobInput) {
+    return await this.db.blob.upsert({
+      where: {
+        workspaceId_key: {
+          workspaceId: blob.workspaceId,
+          key: blob.key,
+        },
+      },
+      update: {
+        mime: blob.mime,
+        size: blob.size,
+      },
+      create: {
+        workspaceId: blob.workspaceId,
+        key: blob.key,
+        mime: blob.mime,
+        size: blob.size,
+      },
+    });
+  }
+
+  async delete(workspaceId: string, key: string, permanently = false) {
+    if (permanently) {
+      await this.db.blob.deleteMany({
+        where: {
+          workspaceId,
+          key,
+        },
+      });
+      this.logger.log(`deleted blob ${workspaceId}/${key} permanently`);
+      return;
+    }
+
+    await this.db.blob.update({
+      where: {
+        workspaceId_key: {
+          workspaceId,
+          key,
+        },
+      },
+      data: {
+        deletedAt: new Date(),
+      },
+    });
+  }
+
+  async get(workspaceId: string, key: string) {
+    return await this.db.blob.findUnique({
+      where: {
+        workspaceId_key: {
+          workspaceId,
+          key,
+        },
+      },
+    });
+  }
+
+  async list(workspaceId: string) {
+    return await this.db.blob.findMany({
+      where: {
+        workspaceId,
+        deletedAt: null,
+      },
+    });
+  }
+
+  async listDeleted(workspaceId: string) {
+    return await this.db.blob.findMany({
+      where: {
+        workspaceId,
+        deletedAt: { not: null },
+      },
+    });
+  }
+
+  async totalSize(workspaceId: string) {
+    const sum = await this.db.blob.aggregate({
+      where: {
+        workspaceId,
+        deletedAt: null,
+      },
+      _sum: {
+        size: true,
+      },
+    });
+
+    return sum._sum.size ?? 0;
+  }
+}
diff --git a/packages/backend/server/src/models/index.ts b/packages/backend/server/src/models/index.ts
index 70fc15ba5..77bc6774a 100644
--- a/packages/backend/server/src/models/index.ts
+++ b/packages/backend/server/src/models/index.ts
@@ -7,6 +7,7 @@ import {
 import { ModuleRef } from '@nestjs/core';
 
 import { ApplyType } from '../base';
+import { BlobModel } from './blob';
 import { CommentModel } from './comment';
 import { CommentAttachmentModel } from './comment-attachment';
 import { AppConfigModel } from './config';
@@ -52,6 +53,7 @@ const MODELS = {
   appConfig: AppConfigModel,
   comment: CommentModel,
   commentAttachment: CommentAttachmentModel,
+  blob: BlobModel,
 };
 
 type ModelsType = {
@@ -103,6 +105,7 @@ const ModelsSymbolProvider: ExistingProvider = {
 })
 export class ModelsModule {}
 
+export * from './blob';
 export * from './comment';
 export * from './comment-attachment';
 export * from './common';