diff --git a/lib/command/base.js b/lib/command/base.js
index 6b7b3e2..449940b 100644
--- a/lib/command/base.js
+++ b/lib/command/base.js
@@ -4,23 +4,9 @@ var EventEmitter = require('events').EventEmitter,
 	inherits = require('util').inherits;
 
 function Command(params) {
-	params = params || {};
-	this.emitIn = params.emitIn;
-	this.emitOut = params.emitOut;
-	this.emitErr = params.emitErr;
-	this.attachStderr = params.attachStderr;
+	this.setParams(params);
 }
 
 exports.Command = Command;
 
 inherits(Command, EventEmitter);
-
-Command.prototype.enableEmitter = function() {
-	this.emitOut = true;
-	return this;
-};
-
-Command.prototype.disableEmitter = function() {
-	this.emitOut = false;
-	return this;
-};
diff --git a/lib/command/spawn.js b/lib/command/spawn.js
index 40f614e..6ff463b 100644
--- a/lib/command/spawn.js
+++ b/lib/command/spawn.js
@@ -6,15 +6,22 @@ var spawn = require('child_process').spawn,
 	_ = require('underscore');
 
 function Command(params) {
-	params = params || {};
-	ParentCommand.call(this, params);
-	this.cwd = params.cwd;
+	ParentCommand.call(this, params || {});
 }
 
 exports.Command = Command;
 
 inherits(Command, ParentCommand);
 
+Command.prototype.setParams = function(params) {
+	if (params.cwd) this.cwd = params.cwd;
+	if (params.emitIn) this.emitIn = params.emitIn;
+	if (params.emitOut) this.emitOut = params.emitOut;
+	if (params.emitErr) this.emitErr = params.emitErr;
+	if (params.attachStderr) this.attachStderr = params.attachStderr;
+	if (params.collectOut) this.collectOut = params.collectOut;
+};
+
 /**
  * Executes `params.cmd` with `params.args` and `params.options`
  */
diff --git a/lib/scm/base.js b/lib/scm/base.js
index 222182a..5190d58 100644
--- a/lib/scm/base.js
+++ b/lib/scm/base.js
@@ -1,22 +1,46 @@
 'use strict';
 
-var ParentCommand = require('../command/spawn').Command,
-	inherits = require('util').inherits;
+var EventEmitter = require('events').EventEmitter,
+	inherits = require('util').inherits,
+	_ = require('underscore');
 
 function Scm(params) {
-	ParentCommand.call(this, params);
-	this.repository = params.repository;
-	if (!this.repository && !this.cwd) throw new Error(
-		'`repository` or `cwd` must be set'
-	);
-	this.collectOut = true;
-	this.emitIn = true;
-	this.attachStderr = true;
+	var self = this;
+
+	EventEmitter.call(self);
+
+	self.repository = params.repository;
+	self.cwd = params.cwd;
+
+	if (!self.repository && !self.cwd) {
+		throw new Error('`repository` or `cwd` must be set');
+	}
+
+	self.command = params.command;
+
+	self.command.setParams({
+		collectOut: true,
+		emitIn: true,
+		attachStderr: true
+	});
+
+	self.command.on('stdin', function(data) {
+		self.emit('stdin', data);
+	});
 }
 
 exports.Scm = Scm;
 
-inherits(Scm, ParentCommand);
+inherits(Scm, EventEmitter);
+
+Scm.prototype.run = function(params, callback) {
+	if (this.cwd) {
+		params.options = params.options || {};
+		params.options.cwd = this.cwd;
+	}
+
+	this.command.run(params, callback);
+};
 
 /**
  * Clone repository to the `dst` update to `rev` and  set `this.cwd` to `dst`
diff --git a/lib/scm/index.js b/lib/scm/index.js
index 89d0ddc..7b74c75 100644
--- a/lib/scm/index.js
+++ b/lib/scm/index.js
@@ -1,6 +1,11 @@
 'use strict';
 
+var SpawnCommand = require('../command/spawn').Command;
+
 exports.createScm = function(params) {
 	var Constructor = require('./' + params.type).Scm;
+
+	params.command = params.command  || new SpawnCommand();
+
 	return new Constructor(params);
 };