diff --git a/server/Database.js b/server/Database.js
index d5409687..7e119a99 100644
--- a/server/Database.js
+++ b/server/Database.js
@@ -37,6 +37,31 @@ class Database {
 
   buildModels() {
     require('./models/User')(this.sequelize)
+    require('./models/FileMetadata')(this.sequelize)
+    require('./models/Library')(this.sequelize)
+    require('./models/LibraryFolder')(this.sequelize)
+    require('./models/LibraryItem')(this.sequelize)
+    require('./models/EBookFile')(this.sequelize)
+    require('./models/Book')(this.sequelize)
+    require('./models/Podcast')(this.sequelize)
+    require('./models/PodcastEpisode')(this.sequelize)
+    require('./models/MediaProgress')(this.sequelize)
+    require('./models/LibraryFile')(this.sequelize)
+    require('./models/Person')(this.sequelize)
+    require('./models/AudioBookmark')(this.sequelize)
+    require('./models/AudioTrack')(this.sequelize)
+    require('./models/BookAuthor')(this.sequelize)
+    require('./models/BookChapter')(this.sequelize)
+    require('./models/Genre')(this.sequelize)
+    require('./models/BookGenre')(this.sequelize)
+    require('./models/BookNarrator')(this.sequelize)
+    require('./models/Series')(this.sequelize)
+    require('./models/BookSeries')(this.sequelize)
+    require('./models/Tag')(this.sequelize)
+    require('./models/BookTag')(this.sequelize)
+    require('./models/PodcastTag')(this.sequelize)
+    require('./models/Collection')(this.sequelize)
+    require('./models/CollectionBook')(this.sequelize)
 
     return this.sequelize.sync()
   }
diff --git a/server/models/AudioBookmark.js b/server/models/AudioBookmark.js
new file mode 100644
index 00000000..7cb3f9a7
--- /dev/null
+++ b/server/models/AudioBookmark.js
@@ -0,0 +1,73 @@
+const { DataTypes, Model } = require('sequelize')
+
+const uppercaseFirst = str => `${str[0].toUpperCase()}${str.substr(1)}`
+
+/*
+ * Polymorphic association: https://sequelize.org/docs/v6/advanced-association-concepts/polymorphic-associations/
+ * Book has many AudioBookmark. PodcastEpisode has many AudioBookmark.
+ */
+module.exports = (sequelize) => {
+  class AudioBookmark extends Model {
+    getMediaItem(options) {
+      if (!this.mediaItemType) return Promise.resolve(null)
+      const mixinMethodName = `get${uppercaseFirst(this.mediaItemType)}`
+      return this[mixinMethodName](options)
+    }
+  }
+
+  AudioBookmark.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    mediaItemId: DataTypes.UUIDV4,
+    mediaItemType: DataTypes.STRING,
+    title: DataTypes.STRING,
+    time: DataTypes.INTEGER
+  }, {
+    sequelize,
+    modelName: 'AudioBookmark'
+  })
+
+  const { User, Book, PodcastEpisode } = sequelize.models
+  Book.hasMany(AudioBookmark, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'book'
+    }
+  })
+  AudioBookmark.belongsTo(Book, { foreignKey: 'mediaItemId', constraints: false })
+
+  PodcastEpisode.hasMany(AudioBookmark, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'podcastEpisode'
+    }
+  })
+  AudioBookmark.belongsTo(PodcastEpisode, { foreignKey: 'mediaItemId', constraints: false })
+
+  AudioBookmark.addHook('afterFind', findResult => {
+    if (!Array.isArray(findResult)) findResult = [findResult]
+    for (const instance of findResult) {
+      if (instance.mediaItemType === 'book' && instance.book !== undefined) {
+        instance.mediaItem = instance.book
+      } else if (instance.mediaItemType === 'podcastEpisode' && instance.podcastEpisode !== undefined) {
+        instance.mediaItem = instance.podcastEpisode
+      }
+      // To prevent mistakes:
+      delete instance.book
+      delete instance.dataValues.book
+      delete instance.podcastEpisode
+      delete instance.dataValues.podcastEpisode
+    }
+  })
+
+
+  User.hasMany(AudioBookmark)
+  AudioBookmark.belongsTo(User)
+
+  return AudioBookmark
+}
\ No newline at end of file
diff --git a/server/models/AudioTrack.js b/server/models/AudioTrack.js
new file mode 100644
index 00000000..d4c5ea7b
--- /dev/null
+++ b/server/models/AudioTrack.js
@@ -0,0 +1,71 @@
+const { DataTypes, Model } = require('sequelize')
+
+const uppercaseFirst = str => `${str[0].toUpperCase()}${str.substr(1)}`
+
+/*
+ * Polymorphic association: https://sequelize.org/docs/v6/advanced-association-concepts/polymorphic-associations/
+ * Book has many AudioTrack. PodcastEpisode has one AudioTrack.
+ */
+module.exports = (sequelize) => {
+  class AudioTrack extends Model {
+    getMediaItem(options) {
+      if (!this.mediaItemType) return Promise.resolve(null)
+      const mixinMethodName = `get${uppercaseFirst(this.mediaItemType)}`
+      return this[mixinMethodName](options)
+    }
+  }
+
+  AudioTrack.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    mediaItemId: DataTypes.UUIDV4,
+    mediaItemType: DataTypes.STRING,
+    index: DataTypes.INTEGER
+  }, {
+    sequelize,
+    modelName: 'AudioTrack'
+  })
+
+  const { Book, PodcastEpisode, FileMetadata } = sequelize.models
+  Book.hasMany(AudioTrack, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'book'
+    }
+  })
+  AudioTrack.belongsTo(Book, { foreignKey: 'mediaItemId', constraints: false })
+
+  PodcastEpisode.hasOne(AudioTrack, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'podcastEpisode'
+    }
+  })
+  AudioTrack.belongsTo(PodcastEpisode, { foreignKey: 'mediaItemId', constraints: false })
+
+  AudioTrack.addHook('afterFind', findResult => {
+    if (!Array.isArray(findResult)) findResult = [findResult]
+    for (const instance of findResult) {
+      if (instance.mediaItemType === 'book' && instance.book !== undefined) {
+        instance.mediaItem = instance.book
+      } else if (instance.mediaItemType === 'podcastEpisode' && instance.podcastEpisode !== undefined) {
+        instance.mediaItem = instance.podcastEpisode
+      }
+      // To prevent mistakes:
+      delete instance.book
+      delete instance.dataValues.book
+      delete instance.podcastEpisode
+      delete instance.dataValues.podcastEpisode
+    }
+  })
+
+  FileMetadata.hasOne(AudioTrack)
+  AudioTrack.belongsTo(FileMetadata)
+
+  return AudioTrack
+}
\ No newline at end of file
diff --git a/server/models/Book.js b/server/models/Book.js
new file mode 100644
index 00000000..a5f6bb68
--- /dev/null
+++ b/server/models/Book.js
@@ -0,0 +1,40 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Book extends Model { }
+
+  Book.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    title: DataTypes.STRING,
+    subtitle: DataTypes.STRING,
+    publishedYear: DataTypes.STRING,
+    publishedDate: DataTypes.STRING,
+    publisher: DataTypes.STRING,
+    description: DataTypes.TEXT,
+    isbn: DataTypes.STRING,
+    asin: DataTypes.STRING,
+    language: DataTypes.STRING,
+    explicit: DataTypes.BOOLEAN,
+    lastCoverSearchQuery: DataTypes.STRING,
+    lastCoverSearch: DataTypes.DATE
+  }, {
+    sequelize,
+    modelName: 'Book'
+  })
+
+  const { LibraryItem, FileMetadata, EBookFile } = sequelize.models
+  LibraryItem.hasOne(Book)
+  Book.belongsTo(LibraryItem)
+
+  FileMetadata.hasOne(Book)
+  Book.belongsTo(FileMetadata, { as: 'ImageFile' }) // Ref: https://sequelize.org/docs/v6/core-concepts/assocs/#defining-an-alias
+
+  EBookFile.hasOne(Book)
+  Book.belongsTo(EBookFile)
+
+  return Book
+}
\ No newline at end of file
diff --git a/server/models/BookAuthor.js b/server/models/BookAuthor.js
new file mode 100644
index 00000000..686c8e89
--- /dev/null
+++ b/server/models/BookAuthor.js
@@ -0,0 +1,31 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookAuthor extends Model { }
+
+  BookAuthor.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'BookAuthor',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Person } = sequelize.models
+  Book.belongsToMany(Person, { through: BookAuthor })
+  Person.belongsToMany(Book, { through: BookAuthor })
+
+  Book.hasMany(BookAuthor)
+  BookAuthor.belongsTo(Book)
+
+  Person.hasMany(BookAuthor)
+  BookAuthor.belongsTo(Person)
+
+  return BookAuthor
+}
\ No newline at end of file
diff --git a/server/models/BookChapter.js b/server/models/BookChapter.js
new file mode 100644
index 00000000..7cbeeeed
--- /dev/null
+++ b/server/models/BookChapter.js
@@ -0,0 +1,27 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookChapter extends Model { }
+
+  BookChapter.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    index: DataTypes.INTEGER,
+    title: DataTypes.STRING,
+    start: DataTypes.INTEGER,
+    end: DataTypes.INTEGER
+  }, {
+    sequelize,
+    modelName: 'BookChapter'
+  })
+
+  const { Book } = sequelize.models
+
+  Book.hasMany(BookChapter)
+  BookChapter.belongsTo(Book)
+
+  return BookChapter
+}
\ No newline at end of file
diff --git a/server/models/BookGenre.js b/server/models/BookGenre.js
new file mode 100644
index 00000000..0fde5353
--- /dev/null
+++ b/server/models/BookGenre.js
@@ -0,0 +1,31 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookGenre extends Model { }
+
+  BookGenre.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'BookGenre',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Genre } = sequelize.models
+  Book.belongsToMany(Genre, { through: BookGenre })
+  Genre.belongsToMany(Book, { through: BookGenre })
+
+  Book.hasMany(BookGenre)
+  BookGenre.belongsTo(Book)
+
+  Genre.hasMany(BookGenre)
+  BookGenre.belongsTo(Genre)
+
+  return BookGenre
+}
\ No newline at end of file
diff --git a/server/models/BookNarrator.js b/server/models/BookNarrator.js
new file mode 100644
index 00000000..d246160e
--- /dev/null
+++ b/server/models/BookNarrator.js
@@ -0,0 +1,31 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookNarrator extends Model { }
+
+  BookNarrator.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'BookNarrator',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Person } = sequelize.models
+  Book.belongsToMany(Person, { through: BookNarrator })
+  Person.belongsToMany(Book, { through: BookNarrator })
+
+  Book.hasMany(BookNarrator)
+  BookNarrator.belongsTo(Book)
+
+  Person.hasMany(BookNarrator)
+  BookNarrator.belongsTo(Person)
+
+  return BookNarrator
+}
\ No newline at end of file
diff --git a/server/models/BookSeries.js b/server/models/BookSeries.js
new file mode 100644
index 00000000..f4cf31a3
--- /dev/null
+++ b/server/models/BookSeries.js
@@ -0,0 +1,32 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookSeries extends Model { }
+
+  BookSeries.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    sequence: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'BookSeries',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Series } = sequelize.models
+  Book.belongsToMany(Series, { through: BookSeries })
+  Series.belongsToMany(Book, { through: BookSeries })
+
+  Book.hasMany(BookSeries)
+  BookSeries.belongsTo(Book)
+
+  Series.hasMany(BookSeries)
+  BookSeries.belongsTo(Series)
+
+  return BookSeries
+}
\ No newline at end of file
diff --git a/server/models/BookTag.js b/server/models/BookTag.js
new file mode 100644
index 00000000..2089f623
--- /dev/null
+++ b/server/models/BookTag.js
@@ -0,0 +1,31 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class BookTag extends Model { }
+
+  BookTag.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'BookTag',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Tag } = sequelize.models
+  Book.belongsToMany(Tag, { through: BookTag })
+  Tag.belongsToMany(Book, { through: BookTag })
+
+  Book.hasMany(BookTag)
+  BookTag.belongsTo(Book)
+
+  Tag.hasMany(BookTag)
+  BookTag.belongsTo(Tag)
+
+  return BookTag
+}
\ No newline at end of file
diff --git a/server/models/Collection.js b/server/models/Collection.js
new file mode 100644
index 00000000..42a41ac6
--- /dev/null
+++ b/server/models/Collection.js
@@ -0,0 +1,25 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Collection extends Model { }
+
+  Collection.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    name: DataTypes.STRING,
+    description: DataTypes.TEXT
+  }, {
+    sequelize,
+    modelName: 'Collection'
+  })
+
+  const { Library } = sequelize.models
+
+  Library.hasMany(Collection)
+  Collection.belongsTo(Library)
+
+  return Collection
+}
\ No newline at end of file
diff --git a/server/models/CollectionBook.js b/server/models/CollectionBook.js
new file mode 100644
index 00000000..8767e95c
--- /dev/null
+++ b/server/models/CollectionBook.js
@@ -0,0 +1,30 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class CollectionBook extends Model { }
+
+  CollectionBook.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'CollectionBook'
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Book, Collection } = sequelize.models
+  Book.belongsToMany(Collection, { through: CollectionBook })
+  Collection.belongsToMany(Book, { through: CollectionBook })
+
+  Book.hasMany(CollectionBook)
+  CollectionBook.belongsTo(Book)
+
+  Collection.hasMany(CollectionBook)
+  CollectionBook.belongsTo(Collection)
+
+  return CollectionBook
+}
\ No newline at end of file
diff --git a/server/models/EBookFile.js b/server/models/EBookFile.js
new file mode 100644
index 00000000..5ae5d629
--- /dev/null
+++ b/server/models/EBookFile.js
@@ -0,0 +1,23 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class EBookFile extends Model { }
+
+  EBookFile.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'EBookFile'
+  })
+
+  const { FileMetadata } = sequelize.models
+
+  FileMetadata.hasOne(EBookFile)
+  EBookFile.belongsTo(FileMetadata)
+
+  return EBookFile
+}
\ No newline at end of file
diff --git a/server/models/FileMetadata.js b/server/models/FileMetadata.js
new file mode 100644
index 00000000..84dc5a1b
--- /dev/null
+++ b/server/models/FileMetadata.js
@@ -0,0 +1,26 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class FileMetadata extends Model { }
+
+  FileMetadata.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    ino: DataTypes.STRING,
+    filename: DataTypes.STRING,
+    ext: DataTypes.STRING,
+    path: DataTypes.STRING,
+    size: DataTypes.BIGINT,
+    mtime: DataTypes.DATE(6),
+    ctime: DataTypes.DATE(6),
+    birthtime: DataTypes.DATE(6)
+  }, {
+    sequelize,
+    modelName: 'FileMetadata'
+  })
+
+  return FileMetadata
+}
\ No newline at end of file
diff --git a/server/models/Genre.js b/server/models/Genre.js
new file mode 100644
index 00000000..52823ae1
--- /dev/null
+++ b/server/models/Genre.js
@@ -0,0 +1,19 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Genre extends Model { }
+
+  Genre.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    name: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'Genre'
+  })
+
+  return Genre
+}
\ No newline at end of file
diff --git a/server/models/Library.js b/server/models/Library.js
new file mode 100644
index 00000000..7e5c0fb5
--- /dev/null
+++ b/server/models/Library.js
@@ -0,0 +1,25 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Library extends Model { }
+
+  Library.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    name: DataTypes.STRING,
+    displayOrder: DataTypes.INTEGER,
+    icon: DataTypes.STRING,
+    mediaType: DataTypes.STRING,
+    provider: DataTypes.STRING,
+    lastScan: DataTypes.DATE,
+    scanVersion: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'Library'
+  })
+
+  return Library
+}
\ No newline at end of file
diff --git a/server/models/LibraryFile.js b/server/models/LibraryFile.js
new file mode 100644
index 00000000..f4839a15
--- /dev/null
+++ b/server/models/LibraryFile.js
@@ -0,0 +1,25 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class LibraryFile extends Model { }
+
+  LibraryFile.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'LibraryFile'
+  })
+
+  const { LibraryItem, FileMetadata } = sequelize.models
+  LibraryItem.hasMany(LibraryFile)
+  LibraryFile.belongsTo(LibraryItem)
+
+  FileMetadata.hasOne(LibraryFile)
+  LibraryFile.belongsTo(FileMetadata)
+
+  return LibraryFile
+}
\ No newline at end of file
diff --git a/server/models/LibraryFolder.js b/server/models/LibraryFolder.js
new file mode 100644
index 00000000..028dcdf3
--- /dev/null
+++ b/server/models/LibraryFolder.js
@@ -0,0 +1,23 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class LibraryFolder extends Model { }
+
+  LibraryFolder.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    path: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'LibraryFolder'
+  })
+
+  const { Library } = sequelize.models
+  Library.hasMany(LibraryFolder)
+  LibraryFolder.belongsTo(Library)
+
+  return LibraryFolder
+}
\ No newline at end of file
diff --git a/server/models/LibraryItem.js b/server/models/LibraryItem.js
new file mode 100644
index 00000000..1a212ef8
--- /dev/null
+++ b/server/models/LibraryItem.js
@@ -0,0 +1,34 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class LibraryItem extends Model { }
+
+  LibraryItem.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    ino: DataTypes.STRING,
+    path: DataTypes.STRING,
+    relPath: DataTypes.STRING,
+    mediaType: DataTypes.STRING,
+    isFile: DataTypes.BOOLEAN,
+    isMissing: DataTypes.BOOLEAN,
+    isInvalid: DataTypes.BOOLEAN,
+    mtime: DataTypes.DATE(6),
+    ctime: DataTypes.DATE(6),
+    birthtime: DataTypes.DATE(6),
+    lastScan: DataTypes.DATE,
+    scanVersion: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'LibraryItem'
+  })
+
+  const { LibraryFolder } = sequelize.models
+  LibraryFolder.hasMany(LibraryItem)
+  LibraryItem.belongsTo(LibraryFolder)
+
+  return LibraryItem
+}
\ No newline at end of file
diff --git a/server/models/MediaProgress.js b/server/models/MediaProgress.js
new file mode 100644
index 00000000..71cd4520
--- /dev/null
+++ b/server/models/MediaProgress.js
@@ -0,0 +1,75 @@
+const { DataTypes, Model } = require('sequelize')
+
+const uppercaseFirst = str => `${str[0].toUpperCase()}${str.substr(1)}`
+
+/*
+ * Polymorphic association: https://sequelize.org/docs/v6/advanced-association-concepts/polymorphic-associations/
+ * Book has many MediaProgress. PodcastEpisode has many MediaProgress.
+ */
+module.exports = (sequelize) => {
+  class MediaProgress extends Model {
+    getMediaItem(options) {
+      if (!this.mediaItemType) return Promise.resolve(null)
+      const mixinMethodName = `get${uppercaseFirst(this.mediaItemType)}`
+      return this[mixinMethodName](options)
+    }
+  }
+
+  MediaProgress.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    mediaItemId: DataTypes.UUIDV4,
+    mediaItemType: DataTypes.STRING,
+    duration: DataTypes.INTEGER,
+    currentTime: DataTypes.INTEGER,
+    isFinished: DataTypes.BOOLEAN,
+    hideFromContinueListening: DataTypes.BOOLEAN,
+    finishedAt: DataTypes.DATE
+  }, {
+    sequelize,
+    modelName: 'MediaProgress'
+  })
+
+  const { Book, PodcastEpisode, User } = sequelize.models
+  Book.hasMany(MediaProgress, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'book'
+    }
+  })
+  MediaProgress.belongsTo(Book, { foreignKey: 'mediaItemId', constraints: false })
+
+  PodcastEpisode.hasMany(MediaProgress, {
+    foreignKey: 'mediaItemId',
+    constraints: false,
+    scope: {
+      mediaItemType: 'podcastEpisode'
+    }
+  })
+  MediaProgress.belongsTo(PodcastEpisode, { foreignKey: 'mediaItemId', constraints: false })
+
+  MediaProgress.addHook('afterFind', findResult => {
+    if (!Array.isArray(findResult)) findResult = [findResult]
+    for (const instance of findResult) {
+      if (instance.mediaItemType === 'book' && instance.book !== undefined) {
+        instance.mediaItem = instance.book
+      } else if (instance.mediaItemType === 'podcastEpisode' && instance.podcastEpisode !== undefined) {
+        instance.mediaItem = instance.podcastEpisode
+      }
+      // To prevent mistakes:
+      delete instance.book
+      delete instance.dataValues.book
+      delete instance.podcastEpisode
+      delete instance.dataValues.podcastEpisode
+    }
+  })
+
+  User.hasMany(MediaProgress)
+  MediaProgress.belongsTo(User)
+
+  return MediaProgress
+}
\ No newline at end of file
diff --git a/server/models/Person.js b/server/models/Person.js
new file mode 100644
index 00000000..6bdccf11
--- /dev/null
+++ b/server/models/Person.js
@@ -0,0 +1,26 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Person extends Model { }
+
+  Person.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    type: DataTypes.STRING,
+    name: DataTypes.STRING,
+    asin: DataTypes.STRING,
+    description: DataTypes.TEXT
+  }, {
+    sequelize,
+    modelName: 'Person'
+  })
+
+  const { FileMetadata } = sequelize.models
+  FileMetadata.hasMany(Person)
+  Person.belongsTo(FileMetadata, { as: 'ImageFile' }) // Ref: https://sequelize.org/docs/v6/core-concepts/assocs/#defining-an-alias
+
+  return Person
+}
\ No newline at end of file
diff --git a/server/models/Podcast.js b/server/models/Podcast.js
new file mode 100644
index 00000000..9bfdf81f
--- /dev/null
+++ b/server/models/Podcast.js
@@ -0,0 +1,46 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Podcast extends Model { }
+
+  Podcast.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    // Metadata
+    title: DataTypes.STRING,
+    author: DataTypes.STRING,
+    releaseDate: DataTypes.STRING,
+    feedUrl: DataTypes.STRING,
+    imageUrl: DataTypes.STRING,
+    description: DataTypes.TEXT,
+    itunesPageUrl: DataTypes.STRING,
+    itunesId: DataTypes.STRING,
+    itunesArtistId: DataTypes.STRING,
+    language: DataTypes.STRING,
+    type: DataTypes.STRING,
+    explicit: DataTypes.BOOLEAN,
+
+    autoDownloadEpisodes: DataTypes.BOOLEAN,
+    autoDownloadSchedule: DataTypes.STRING,
+    lastEpisodeCheck: DataTypes.DATE,
+    maxEpisodesToKeep: DataTypes.INTEGER,
+    maxNewEpisodesToDownload: DataTypes.INTEGER,
+    lastCoverSearchQuery: DataTypes.STRING,
+    lastCoverSearch: DataTypes.DATE
+  }, {
+    sequelize,
+    modelName: 'Podcast'
+  })
+
+  const { LibraryItem, FileMetadata } = sequelize.models
+  LibraryItem.hasOne(Podcast)
+  Podcast.belongsTo(LibraryItem)
+
+  FileMetadata.hasOne(Podcast)
+  Podcast.belongsTo(FileMetadata, { as: 'ImageFile' }) // Ref: https://sequelize.org/docs/v6/core-concepts/assocs/#defining-an-alias
+
+  return Podcast
+}
\ No newline at end of file
diff --git a/server/models/PodcastEpisode.js b/server/models/PodcastEpisode.js
new file mode 100644
index 00000000..73693c8a
--- /dev/null
+++ b/server/models/PodcastEpisode.js
@@ -0,0 +1,34 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class PodcastEpisode extends Model { }
+
+  PodcastEpisode.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    index: DataTypes.INTEGER,
+    season: DataTypes.STRING,
+    episode: DataTypes.STRING,
+    episodeType: DataTypes.STRING,
+    title: DataTypes.STRING,
+    subtitle: DataTypes.STRING(1000),
+    description: DataTypes.TEXT,
+    pubDate: DataTypes.STRING,
+    enclosureURL: DataTypes.STRING,
+    enclosureLength: DataTypes.BIGINT,
+    enclosureType: DataTypes.STRING,
+    publishedAt: DataTypes.DATE
+  }, {
+    sequelize,
+    modelName: 'PodcastEpisode'
+  })
+
+  const { Podcast } = sequelize.models
+  Podcast.hasMany(PodcastEpisode)
+  PodcastEpisode.belongsTo(Podcast)
+
+  return PodcastEpisode
+}
\ No newline at end of file
diff --git a/server/models/PodcastTag.js b/server/models/PodcastTag.js
new file mode 100644
index 00000000..4a6c54a0
--- /dev/null
+++ b/server/models/PodcastTag.js
@@ -0,0 +1,31 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class PodcastTag extends Model { }
+
+  PodcastTag.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    }
+  }, {
+    sequelize,
+    modelName: 'PodcastTag',
+    timestamps: false
+  })
+
+  // Super Many-to-Many
+  // ref: https://sequelize.org/docs/v6/advanced-association-concepts/advanced-many-to-many/#the-best-of-both-worlds-the-super-many-to-many-relationship
+  const { Podcast, Tag } = sequelize.models
+  Podcast.belongsToMany(Tag, { through: PodcastTag })
+  Tag.belongsToMany(Podcast, { through: PodcastTag })
+
+  Podcast.hasMany(PodcastTag)
+  PodcastTag.belongsTo(Podcast)
+
+  Tag.hasMany(PodcastTag)
+  PodcastTag.belongsTo(Tag)
+
+  return PodcastTag
+}
\ No newline at end of file
diff --git a/server/models/Series.js b/server/models/Series.js
new file mode 100644
index 00000000..814b3691
--- /dev/null
+++ b/server/models/Series.js
@@ -0,0 +1,20 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Series extends Model { }
+
+  Series.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    name: DataTypes.STRING,
+    description: DataTypes.TEXT
+  }, {
+    sequelize,
+    modelName: 'Series'
+  })
+
+  return Series
+}
\ No newline at end of file
diff --git a/server/models/Tag.js b/server/models/Tag.js
new file mode 100644
index 00000000..4268f4af
--- /dev/null
+++ b/server/models/Tag.js
@@ -0,0 +1,19 @@
+const { DataTypes, Model } = require('sequelize')
+
+module.exports = (sequelize) => {
+  class Tag extends Model { }
+
+  Tag.init({
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    name: DataTypes.STRING
+  }, {
+    sequelize,
+    modelName: 'Tag'
+  })
+
+  return Tag
+}
\ No newline at end of file
diff --git a/server/models/User.js b/server/models/User.js
index b1977439..a15b77f6 100644
--- a/server/models/User.js
+++ b/server/models/User.js
@@ -4,7 +4,18 @@ module.exports = (sequelize) => {
   class User extends Model { }
 
   User.init({
-    username: DataTypes.STRING
+    id: {
+      type: DataTypes.UUID,
+      defaultValue: DataTypes.UUIDV4,
+      primaryKey: true
+    },
+    username: DataTypes.STRING,
+    pash: DataTypes.STRING,
+    type: DataTypes.STRING,
+    token: DataTypes.STRING,
+    isActive: DataTypes.BOOLEAN,
+    isLocked: DataTypes.BOOLEAN,
+    lastSeen: DataTypes.DATE
   }, {
     sequelize,
     modelName: 'User'