diff --git a/src/browser/Types.d.ts b/src/browser/Types.d.ts
index b2ff29d7..fcae7e47 100644
--- a/src/browser/Types.d.ts
+++ b/src/browser/Types.d.ts
@@ -14,8 +14,6 @@ export interface ITerminal extends IPublicTerminal, ICoreTerminal {
   element: HTMLElement | undefined;
   screenElement: HTMLElement | undefined;
   browser: IBrowser;
-  buffer: IBuffer;
-  buffers: IBufferSet;
   viewport: IViewport | undefined;
   // TODO: We should remove options once components adopt optionsService
   options: ITerminalOptions;
diff --git a/src/common/Types.d.ts b/src/common/Types.d.ts
index 51f7e172..950e5e57 100644
--- a/src/common/Types.d.ts
+++ b/src/common/Types.d.ts
@@ -8,10 +8,16 @@ import { IEvent, IEventEmitter } from 'common/EventEmitter';
 import { IDeleteEvent, IInsertEvent } from 'common/CircularList';
 import { IParams } from 'common/parser/Types';
 import { IOptionsService, IUnicodeService } from 'common/services/Services';
+import { IBuffer, IBufferSet } from 'common/buffer/Types';
 
 export interface ICoreTerminal {
   optionsService: IOptionsService;
   unicodeService: IUnicodeService;
+  buffers: IBufferSet;
+  registerCsiHandler(id: IFunctionIdentifier, callback: (params: IParams) => boolean | Promise<boolean>): IDisposable;
+  registerDcsHandler(id: IFunctionIdentifier, callback: (data: string, param: IParams) => boolean | Promise<boolean>): IDisposable;
+  registerEscHandler(id: IFunctionIdentifier, callback: () => boolean | Promise<boolean>): IDisposable;
+  registerOscHandler(ident: number, callback: (data: string) => boolean | Promise<boolean>): IDisposable;
 }
 
 export interface IDisposable {
diff --git a/src/common/public/BufferApiView.ts b/src/common/public/BufferApiView.ts
index f6f12744..56ed0155 100644
--- a/src/common/public/BufferApiView.ts
+++ b/src/common/public/BufferApiView.ts
@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) 2021 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 import { IBuffer as IBufferApi, IBufferLine as IBufferLineApi,  IBufferCell as IBufferCellApi } from 'xterm';
 import { IBuffer } from 'common/buffer/Types';
 import { BufferLineApiView } from 'common/public/BufferLineApiView';
diff --git a/src/common/public/BufferLineApiView.ts b/src/common/public/BufferLineApiView.ts
index 2482adb7..60375015 100644
--- a/src/common/public/BufferLineApiView.ts
+++ b/src/common/public/BufferLineApiView.ts
@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) 2021 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 import { CellData } from 'common/buffer/CellData';
 import { IBufferLine, ICellData } from 'common/Types';
 import { IBufferCell as IBufferCellApi, IBufferLine as IBufferLineApi } from 'xterm';
diff --git a/src/common/public/BufferNamespaceApi.ts b/src/common/public/BufferNamespaceApi.ts
index 7c0f2287..c7bee600 100644
--- a/src/common/public/BufferNamespaceApi.ts
+++ b/src/common/public/BufferNamespaceApi.ts
@@ -1,7 +1,13 @@
+/**
+ * Copyright (c) 2021 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 import { IBuffer as IBufferApi, IBufferNamespace as IBufferNamespaceApi } from 'xterm';
 import { BufferApiView } from 'common/public/BufferApiView';
 import { IEvent, EventEmitter } from 'common/EventEmitter';
 import { CoreTerminal } from 'common/CoreTerminal';
+import { ICoreTerminal } from 'common/Types';
 
 export class BufferNamespaceApi implements IBufferNamespaceApi {
   private _normal: BufferApiView;
@@ -9,7 +15,7 @@ export class BufferNamespaceApi implements IBufferNamespaceApi {
   private _onBufferChange = new EventEmitter<IBufferApi>();
   public get onBufferChange(): IEvent<IBufferApi> { return this._onBufferChange.event; }
 
-  constructor(private _core: CoreTerminal) {
+  constructor(private _core: ICoreTerminal) {
     this._normal = new BufferApiView(this._core.buffers.normal, 'normal');
     this._alternate = new BufferApiView(this._core.buffers.alt, 'alternate');
     this._core.buffers.onBufferActivate(() => this._onBufferChange.fire(this.active));
diff --git a/src/common/public/ParserApi.ts b/src/common/public/ParserApi.ts
index ffc5a0fd..67df4be5 100644
--- a/src/common/public/ParserApi.ts
+++ b/src/common/public/ParserApi.ts
@@ -1,9 +1,14 @@
+/**
+ * Copyright (c) 2021 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 import { IParams } from 'common/parser/Types';
-import { CoreTerminal } from 'common/CoreTerminal';
 import { IDisposable, IFunctionIdentifier, IParser } from 'xterm';
+import { ICoreTerminal } from 'common/Types';
 
 export class ParserApi implements IParser {
-  constructor(private _core: CoreTerminal) { }
+  constructor(private _core: ICoreTerminal) { }
 
   public registerCsiHandler(id: IFunctionIdentifier, callback: (params: (number | number[])[]) => boolean | Promise<boolean>): IDisposable {
     return this._core.registerCsiHandler(id, (params: IParams) => callback(params.toArray()));
diff --git a/src/common/public/UnicodeApi.ts b/src/common/public/UnicodeApi.ts
index 141863dc..8a669a05 100644
--- a/src/common/public/UnicodeApi.ts
+++ b/src/common/public/UnicodeApi.ts
@@ -1,8 +1,13 @@
-import { CoreTerminal } from 'common/CoreTerminal';
+/**
+ * Copyright (c) 2021 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { ICoreTerminal } from 'common/Types';
 import { IUnicodeHandling, IUnicodeVersionProvider } from 'xterm';
 
 export class UnicodeApi implements IUnicodeHandling {
-  constructor(private _core: CoreTerminal) { }
+  constructor(private _core: ICoreTerminal) { }
 
   public register(provider: IUnicodeVersionProvider): void {
     this._core.unicodeService.register(provider);