diff --git a/extensions/git/src/api/git.d.ts b/extensions/git/src/api/git.d.ts
index 698fcc4fb16..7d6f07a963d 100644
--- a/extensions/git/src/api/git.d.ts
+++ b/extensions/git/src/api/git.d.ts
@@ -56,21 +56,68 @@ export interface Remote {
 	readonly isReadOnly: boolean;
 }
 
+export interface Change {
+	// TODO
+}
+
 export interface RepositoryState {
 	readonly HEAD: Branch | undefined;
 	readonly refs: Ref[];
 	readonly remotes: Remote[];
 	readonly submodules: Submodule[];
 	readonly rebaseCommit: Commit | undefined;
+
+	readonly mergeChanges: Change[];
+	readonly indexChanges: Change[];
+	readonly workingTreeChanges: Change[];
+
 	readonly onDidChange: Event<void>;
 }
 
+export const enum ConfigScope {
+	System,
+	Global,
+	Local
+}
+
 export interface Repository {
+
 	readonly rootUri: Uri;
 	readonly inputBox: InputBox;
 	readonly state: RepositoryState;
 
+	getConfigs(scope: ConfigScope): Promise<{ key: string; value: string; }[]>;
+	getConfig(scope: ConfigScope, key: string): Promise<string>;
+	setConfig(scope: ConfigScope, key: string, value: string): Promise<string>;
+
+	show(ref: string, path: string): Promise<string>;
+	getCommit(ref: string): Promise<Commit>;
+	getObjectDetails(treeish: string, path: string): Promise<{ mode: string, object: string, size: number }>;
+
+	diffWithHEAD(path: string): Promise<string>;
+	diffWith(ref: string, path: string): Promise<string>;
+	diffIndexWithHEAD(path: string): Promise<string>;
+	diffIndexWith(ref: string, path: string): Promise<string>;
+	diffBlobs(object1: string, object2: string): Promise<string>;
+	diffBetween(ref1: string, ref2: string, path: string): Promise<string>;
+
+	hashObject(data: string): Promise<string>;
+
+	createBranch(name: string, checkout: boolean, ref?: string): Promise<void>;
+	deleteBranch(name: string): Promise<void>;
+	getBranch(name: string): Promise<Branch>;
+	setBranchUpstream(name: string, upstream: string): Promise<void>;
+
+	getMergeBase(ref1: string, ref2: string): Promise<string>;
+
 	status(): Promise<void>;
+	checkout(treeish: string): Promise<void>;
+
+	addRemote(name: string, url: string): Promise<void>;
+	removeRemote(name: string): Promise<void>;
+
+	fetch(remote?: string, ref?: string): Promise<void>;
+	pull(): Promise<void>;
 }
 
 export interface API {
diff --git a/extensions/git/src/autofetch.ts b/extensions/git/src/autofetch.ts
index 758dc82182c..3522414fb79 100644
--- a/extensions/git/src/autofetch.ts
+++ b/extensions/git/src/autofetch.ts
@@ -102,7 +102,7 @@ export class AutoFetcher {
 			}
 
 			try {
-				await this.repository.fetch();
+				await this.repository.fetchDefault();
 			} catch (err) {
 				if (err.gitErrorCode === GitErrorCodes.AuthenticationFailed) {
 					this.disable();
diff --git a/extensions/git/src/commands.ts b/extensions/git/src/commands.ts
index 25f3bc2979e..13f6f4b687e 100644
--- a/extensions/git/src/commands.ts
+++ b/extensions/git/src/commands.ts
@@ -1235,7 +1235,7 @@ export class CommandCenter {
 		}
 
 		const name = result.replace(/^\.|\/\.|\.\.|~|\^|:|\/$|\.lock$|\.lock\/|\\|\*|\s|^\s*$|\.$/g, '-');
-		await repository.branch(name);
+		await repository.branch(name, true);
 	}
 
 	@command('git.deleteBranch', { repository: true })
@@ -1355,7 +1355,7 @@ export class CommandCenter {
 			return;
 		}
 
-		await repository.fetch();
+		await repository.fetchDefault();
 	}
 
 	@command('git.pullFrom', { repository: true })
diff --git a/extensions/git/src/contentProvider.ts b/extensions/git/src/contentProvider.ts
index 443dd774f2a..5c3dd22b1e4 100644
--- a/extensions/git/src/contentProvider.ts
+++ b/extensions/git/src/contentProvider.ts
@@ -92,7 +92,7 @@ export class GitContentProvider {
 				return '';
 			}
 
-			return await repository.diff(path, { cached: ref === 'index' });
+			return await repository.diff(path, ref === 'index');
 		}
 
 		const repository = this.model.getRepository(uri);
diff --git a/extensions/git/src/git.ts b/extensions/git/src/git.ts
index 36e7b4f53ec..f861de0393a 100644
--- a/extensions/git/src/git.ts
+++ b/extensions/git/src/git.ts
@@ -654,10 +654,6 @@ export function parseLsFiles(raw: string): LsFilesElement[] {
 		.map(([, mode, object, stage, file]) => ({ mode, object, stage, file }));
 }
 
-export interface DiffOptions {
-	cached?: boolean;
-}
-
 export class Repository {
 
 	constructor(
@@ -828,10 +824,10 @@ export class Repository {
 		}
 	}
 
-	async diff(path: string, options: DiffOptions = {}): Promise<string> {
+	async diff(path: string, cached = false): Promise<string> {
 		const args = ['diff'];
 
-		if (options.cached) {
+		if (cached) {
 			args.push('--cached');
 		}
 
@@ -841,6 +837,20 @@ export class Repository {
 		return result.stdout;
 	}
 
+	async diffBetween(ref1: string, ref2: string, path: string): Promise<string> {
+		const args = ['diff', `${ref1}...${ref2}`, '--', path];
+		const result = await this.run(args);
+
+		return result.stdout.trim();
+	}
+
+	async getMergeBase(ref1: string, ref2: string): Promise<string> {
+		const args = ['merge-base', ref1, ref2];
+		const result = await this.run(args);
+
+		return result.stdout.trim();
+	}
+
 	async add(paths: string[]): Promise<void> {
 		const args = ['add', '-A', '--'];
 
@@ -961,8 +971,13 @@ export class Repository {
 		throw commitErr;
 	}
 
-	async branch(name: string, checkout: boolean): Promise<void> {
+	async branch(name: string, checkout: boolean, ref?: string): Promise<void> {
 		const args = checkout ? ['checkout', '-q', '-b', name] : ['branch', '-q', name];
+
+		if (ref) {
+			args.push(ref);
+		}
+
 		await this.run(args);
 	}
 
@@ -976,6 +991,11 @@ export class Repository {
 		await this.run(args);
 	}
 
+	async setBranchUpstream(name: string, upstream: string): Promise<void> {
+		const args = ['branch', '--set-upstream-to', upstream, name];
+		await this.run(args);
+	}
+
 	async deleteRef(ref: string): Promise<void> {
 		const args = ['update-ref', '-d', ref];
 		await this.run(args);
@@ -1073,7 +1093,22 @@ export class Repository {
 		}
 	}
 
-	async fetch(): Promise<void> {
+	async addRemote(name: string, url: string): Promise<void> {
+		const args = ['remote', 'add', name, url];
+		await this.run(args);
+	}
+
+	async fetch(remote?: string, ref?: string): Promise<void> {
+		const args = ['fetch'];
+
+		if (remote) {
+			args.push(remote);
+
+			if (ref) {
+				args.push(ref);
+			}
+		}
+
 		try {
 			await this.run(['fetch']);
 		} catch (err) {
diff --git a/extensions/git/src/repository.ts b/extensions/git/src/repository.ts
index 2135fa69091..d9caa7787d2 100644
--- a/extensions/git/src/repository.ts
+++ b/extensions/git/src/repository.ts
@@ -655,8 +655,8 @@ export class Repository implements Disposable {
 		await this.run(Operation.Status);
 	}
 
-	diff(path: string, options: DiffOptions = {}): Promise<string> {
-		return this.run(Operation.Diff, () => this.repository.diff(path, options));
+	diff(path: string, cached = false): Promise<string> {
+		return this.run(Operation.Diff, () => this.repository.diff(path, cached));
 	}
 
 	async add(resources: Uri[]): Promise<void> {
@@ -746,7 +746,7 @@ export class Repository implements Disposable {
 		});
 	}
 
-	async branch(name: string): Promise<void> {
+	async branch(name: string, checkout: boolean, ref?: string): Promise<void> {
 		await this.run(Operation.Branch, () => this.repository.branch(name, true));
 	}
 
@@ -783,7 +783,11 @@ export class Repository implements Disposable {
 	}
 
 	@throttle
-	async fetch(): Promise<void> {
+	async fetchDefault(): Promise<void> {
+		await this.run(Operation.Fetch, () => this.repository.fetch());
+	}
+
+	async fetch(remote?: string, ref?: string): Promise<void> {
 		await this.run(Operation.Fetch, () => this.repository.fetch());
 	}