diff --git a/src/coffee/models/crafting/crafting_node.coffee b/src/coffee/models/crafting/crafting_node.coffee
new file mode 100644
index 000000000..260317803
--- /dev/null
+++ b/src/coffee/models/crafting/crafting_node.coffee
@@ -0,0 +1,99 @@
+###
+Crafting Guide - crafting_node.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+########################################################################################################################
+
+module.exports = class CraftingNode
+
+    constructor: (options={})->
+        if not options.modPack? then throw new Error 'options.modPack is required'
+
+        @modPack = options.modPack
+
+        @_children = []
+        @_complete = null
+        @_valid    = null
+
+    # Public Methods ###############################################################################
+
+    expand: (queue=[])->
+        return queue if @children.length > 0
+
+        for child in @_createChildren()
+            child.parent = this
+            @_children.push child
+            queue.push child
+        return queue
+
+    getNode: (path)->
+        return null unless _.isArray(path) and path.length > 0
+
+        child = @children[path[0]]
+        return null unless child?
+
+        return child.getPath path[1..]
+
+    # Property Methods #############################################################################
+
+    getChildren: ->
+        return @_children
+
+    isComplete: ->
+        if not @_complete?
+            @_complete = @_checkCompleteness()
+        return @_complete
+
+    getCompleteText: ->
+        return if @complete then "✓" else "✗"
+
+    getDepth: ->
+        maxDepth = 1
+        for child in @children
+            maxDepth = Math.max maxDepth, child.getDepth() + 1
+        return maxDepth
+
+    getSize: ->
+        size = 1
+        for child in @children
+            size += child.size
+        return size
+
+    getNodeType: ->
+        return @_nodeType
+
+    isValid: ->
+        return @_valid if @_valid?
+
+        valid = @_checkValidity()
+        @_valid = false if not valid
+
+        return valid
+
+    Object.defineProperties @prototype,
+        children:     { get:@prototype.getChildren     }
+        complete:     { get:@prototype.isComplete      }
+        completeText: { get:@prototype.getCompleteText }
+        depth:        { get:@prototype.getDepth        }
+        size:         { get:@prototype.getSize         }
+
+
+    # Virtual Methods ##############################################################################
+
+    # Subclasses must override this method to create such children as are appropriate for that kind of node. The new
+    # nodes should be appended to the given array.
+    _createChildren: (result)->
+        throw new Error "#{@constructor.name} must override the _createChildren method"
+
+    # Subclasses must override this method to indicate whether the node has at least one "complete" subtree rooted with
+    # itself. Completeness may be defined differently by different subclasses.
+    _checkCompleteness: ->
+        throw new Error "#{@constructor.name} must override the _checkCompletness method"
+
+    # Subclasses must override this method to determine whether the subtree represented by a node should still be
+    # explored for having a useful crafting plan.
+    _checkValidity: ->
+        throw new Error "#{@constructor.name} must override the _checkValidity method"
diff --git a/src/coffee/models/crafting/graph_builder.coffee b/src/coffee/models/crafting/graph_builder.coffee
new file mode 100644
index 000000000..4d83efc55
--- /dev/null
+++ b/src/coffee/models/crafting/graph_builder.coffee
@@ -0,0 +1,72 @@
+###
+Crafting Guide - graph_builder.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+Inventory     = require '../inventory'
+InventoryNode = require './inventory_node'
+
+########################################################################################################################
+
+module.exports = class GraphBuilder
+
+    constructor: (options={})->
+        if not options.modPack? then throw new Error 'options.modPack is required'
+
+        @modPack = options.modPack
+        @_wanted = options.wanted ?= new Inventory
+
+        @_wanted.on 'change', => @reset()
+
+        @reset()
+
+    # Public Methods ###############################################################################
+
+    expandGraph: (steps=null)->
+        maxSteps = if steps? then @_stepCount + steps else Number.MAX_VALUE
+        @_queue ?= []
+
+        while true
+            break if @_queue.length is 0
+            break if @_stepCount >= maxSteps
+
+            node = @_queue.shift()
+            break unless node?
+
+            node.expand @_queue
+            @_stepCount += 1
+
+    reset: ->
+        @_rootNode = new InventoryNode modPack:@modPack, inventory:@wanted
+        @_queue = [@_rootNode]
+        @_stepCount = 0
+
+    # Property Methods #############################################################################
+
+    isComplete: ->
+        return false unless @_rootNode?
+        return false unless @_queue?
+        return false unless @_queue.length is 0
+        return true
+
+    getRootNode: ->
+        return @_rootNode
+
+    getStepCount: ->
+        return @_stepCount
+
+    getWanted: ->
+        return @_wanted
+
+    Object.defineProperties @prototype,
+        complete:  { get:@prototype.isComplete   }
+        rootNode:  { get:@prototype.getRootNode  }
+        stepCount: { get:@prototype.getStepCount }
+        wanted:    { get:@prototype.getWanted    }
+
+    # Object Overrides ############################################################################
+
+    toString: (indent='')->
+        "Build Tree\n#{@_rootNode.toString(indent + '    ')}"
diff --git a/src/coffee/models/crafting/inventory_node.coffee b/src/coffee/models/crafting/inventory_node.coffee
new file mode 100644
index 000000000..fa7614836
--- /dev/null
+++ b/src/coffee/models/crafting/inventory_node.coffee
@@ -0,0 +1,47 @@
+###
+Crafting Guide - crafting_plan_node.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+CraftingNode = require './crafting_node'
+ItemNode     = require './item_node'
+
+########################################################################################################################
+
+module.exports = class InventoryNode extends CraftingNode
+
+    constructor: (options={})->
+        if not options.inventory? then throw new Error 'options.inventory is required'
+        super options
+
+        @inventory = options.inventory
+
+    # CraftingNode Overrides #######################################################################
+
+    _createChildren: (result=[])->
+        @inventory.each (stack)=>
+            item = @modPack.findItem stack.itemSlug
+            if not item? then throw new Error "Could not find an item for slug: #{stack.itemSlug}"
+            result.push new ItemNode modPack:@modPack, item:item
+        return result
+
+    _checkCompleteness: ->
+        for child in @children
+            return false unless child.isComplete
+        return true
+
+    _checkValidity: ->
+        for child in @children
+            return false unless child.isValid
+
+    # Object Overrides #############################################################################
+
+    toString: (indent='')->
+        completeText = if @complete then 'complete' else 'incomplete'
+        parts = ["#{indent}#{@completeText} InventoryNode for #{@inventory}"]
+        nextIndent = indent + '    '
+        for child in @children
+            parts.push child.toString nextIndent
+        return parts.join '\n'
diff --git a/src/coffee/models/crafting/item_node.coffee b/src/coffee/models/crafting/item_node.coffee
new file mode 100644
index 000000000..4c6ee324e
--- /dev/null
+++ b/src/coffee/models/crafting/item_node.coffee
@@ -0,0 +1,69 @@
+###
+Crafting Guide - item_node.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+CraftingNode = require './crafting_node'
+RecipeNode   = require './recipe_node'
+
+########################################################################################################################
+
+module.exports = class ItemNode extends CraftingNode
+
+    constructor: (options={})->
+        if not options.item? then throw new Error 'options.item is required'
+        super options
+
+        @item = options.item
+        @_recipes = null
+
+    # Property Methods #############################################################################
+
+    getRecipes: ->
+        if not @_recipes?
+            @_recipes = @modPack.findRecipes @item.slug
+        return @_recipes or []
+
+    isGatherable: ->
+        return true if @item.isGatherable
+        return true unless @getRecipes().length > 0
+        return false
+
+    Object.defineProperties @prototype,
+        gatherable: { get:@prototype.isGatherable }
+        recipes: { get:@prototype.getRecipes }
+
+    # CraftingNode Overrides #######################################################################
+
+    _createChildren: (result=[])->
+        recipes = @getRecipes()
+        return [] unless recipes.length > 0
+
+        for recipe in recipes
+            result.push new RecipeNode modPack:@modPack, recipe:recipe
+
+        return result
+
+    _checkCompleteness: ->
+        return true if @gatherable
+        return false unless @children?
+
+        for child in @children
+            return true if child.isComplete
+        return false
+
+    _checkValidity: ->
+        for child in @children
+            return true if child.isValid
+
+    # Object Overrides #############################################################################
+
+    toString: (indent)->
+        completeText = if @complete then 'complete' else 'incomplete'
+        parts = ["#{indent}#{@completeText} ItemNode for #{@item.name}"]
+        nextIndent = indent + '    '
+        for child in @children
+            parts.push child.toString nextIndent
+        return parts.join '\n'
diff --git a/src/coffee/models/crafting/recipe_node.coffee b/src/coffee/models/crafting/recipe_node.coffee
new file mode 100644
index 000000000..4fad67cc4
--- /dev/null
+++ b/src/coffee/models/crafting/recipe_node.coffee
@@ -0,0 +1,61 @@
+###
+Crafting Guide - recipe_node.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+CraftingNode = require './crafting_node'
+# ItemNode     = require './item_node' # don't include here, causes a cycle
+
+########################################################################################################################
+
+module.exports = class RecipeNode extends CraftingNode
+
+    constructor: (options={})->
+        if not options.recipe? then throw new Error 'options.recipe is required'
+        super options
+
+        @recipe = options.recipe
+
+    # CraftingNode Overrides #######################################################################
+
+    _createChildren: (result=[])->
+        ItemNode = require './item_node' # include here to avoid a cycle
+
+        for stack in @recipe.input
+            item = @modPack.findItem stack.itemSlug
+            result.push new ItemNode modPack:@modPack, item:item
+        return result
+
+    _checkCompleteness: ->
+        for child in @children
+            return false unless child.isComplete
+        return true
+
+    _checkValidity: ->
+        for child in @children
+            return false unless child.isValid
+
+        return false if @_isRepeatedRecipe()
+        return true
+
+    # Private Methods ##############################################################################
+
+    _isRepeatedRecipe: ->
+        nextParent = @parent
+        while nextParent?
+            return true if nextParent.recipe is @recipe
+            nextParent = nextParent.parent
+
+        return false
+
+    # Object Overrides ############################################################################
+
+    toString: (indent)->
+        completeText = if @complete then 'complete' else 'incomplete'
+        parts = ["#{indent}#{@completeText} RecipeNode for #{@recipe.slug}"]
+        nextIndent = indent + '    '
+        for child in @children
+            parts.push child.toString nextIndent
+        return parts.join '\n'
diff --git a/src/coffee/models/inventory.coffee b/src/coffee/models/inventory.coffee
index 8aca9b788..f26184c39 100644
--- a/src/coffee/models/inventory.coffee
+++ b/src/coffee/models/inventory.coffee
@@ -170,7 +170,7 @@ module.exports = class Inventory extends BaseModel
     # Object Overrides #############################################################################
 
     toString: ->
-        result = [@constructor.name, " (", @cid, ") { items: ["]
+        result = [@constructor.name, " (", @cid, ") {items: ["]
 
         needsDelimiter = false
         @each (stack)->
diff --git a/test/crafting/graph_builder.test.coffee b/test/crafting/graph_builder.test.coffee
new file mode 100644
index 000000000..aaeb0e633
--- /dev/null
+++ b/test/crafting/graph_builder.test.coffee
@@ -0,0 +1,142 @@
+###
+Crafting Guide - crafting_node.test.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+GraphBuilder = require '../../src/coffee/models/crafting/graph_builder'
+ItemSlug     = require '../../src/coffee/models/item_slug'
+Mod          = require '../../src/coffee/models/mod'
+ModPack      = require '../../src/coffee/models/mod_pack'
+ModVersion   = require '../../src/coffee/models/mod_version'
+
+########################################################################################################################
+
+SAMPLE_MOD_VERSION_TEXT = """
+    schema: 1
+
+    item: Charcoal
+        recipe:
+            input: 8 Oak Wood, Coal
+            pattern: .0. ... .1.
+
+    item: Crafting Table
+        recipe:
+            input: Oak Planks
+            pattern: .00 .00 ...
+
+    item: Coal
+
+    item: Cobblestone
+
+    item: Furnace
+        recipe:
+            input: Cobblestone
+            pattern: 000 0.0 000
+            tools: Crafting Table
+
+    item: Iron Ore
+
+    item: Iron Ingot
+        recipe:
+            input: 8 Iron Ore, Charcoal
+            pattern: .0. ... .1.
+            tools: Furnace
+        recipe:
+            input: 8 Iron Ore, Coal
+            pattern: .0. ... .1.
+            tools: Furnace
+
+    item: Iron Sword
+        recipe:
+            input: Iron Ingot, Stick
+            pattern: .0. .0. .1.
+            tools: Crafting Table
+
+    item: Lever
+        recipe:
+            input: Stick, Cobblestone
+            pattern: .0. .1. ...
+
+    item: Oak Planks
+        recipe:
+            input: Oak Wood
+            pattern: ... .0. ...
+            quantity: 4
+
+    item: Oak Wood
+
+    item: Stick
+        recipe:
+            input: Oak Planks
+            pattern: .0. .0. ...
+            quantity: 4
+"""
+
+builder = mod = modPack = modVersion = null
+
+########################################################################################################################
+
+describe.only 'GraphBuilder.coffee', ->
+
+    beforeEach ->
+        modPack = new ModPack
+
+        mod = new Mod name:'Test', slug:'test'
+        modPack.addMod mod
+
+        modVersion = new ModVersion modSlug:'test', version:'0.0'
+        modVersion.parse SAMPLE_MOD_VERSION_TEXT
+        mod.addModVersion modVersion
+
+        builder = new GraphBuilder modPack:modPack
+
+    describe 'expand', ->
+
+        it 'can work a few steps at a time', ->
+            builder.wanted.add ItemSlug.slugify 'test__iron_sword'
+            builder.expandGraph 9
+
+            builder.rootNode.depth.should.equal 6
+            builder.rootNode.size.should.equal 13
+            builder.complete.should.be.false
+
+            builder.expandGraph 9
+
+            builder.rootNode.depth.should.equal 8
+            builder.rootNode.size.should.equal 18
+            builder.complete.should.be.true
+
+        it 'works properly with an empty inventory', ->
+            builder.expandGraph 100
+
+            builder.rootNode.depth.should.equal 1
+            builder.rootNode.size.should.equal 1
+            builder.complete.should.be.true
+
+        describe 'can build a tree for', ->
+
+            runSingleItemTreeBuildingTest = (slug, depth, size)->
+                builder.wanted.add ItemSlug.slugify slug
+                builder.expandGraph 100
+
+                builder.rootNode.depth.should.equal depth
+                builder.rootNode.size.should.equal size
+                builder.complete.should.be.true
+
+            it 'a gatherable item', ->
+                runSingleItemTreeBuildingTest 'test__oak_wood', 2, 2
+
+            it 'a single-step item', ->
+                runSingleItemTreeBuildingTest 'test__crafting_table', 6, 6
+
+            it 'an item with multiple inputs', ->
+                runSingleItemTreeBuildingTest 'test__lever', 8, 9
+
+            it 'can make a tree for an item with multiple recipes', ->
+                runSingleItemTreeBuildingTest 'test__iron_ingot', 6, 11
+
+            it 'can make a tree for an item with multiple inputs and multiple recipes', ->
+                runSingleItemTreeBuildingTest 'test__iron_sword', 8, 18
+                logger.debug builder.toString()
diff --git a/test/test_helper.coffee b/test/test_helper.coffee
index d4b7bbd07..744bc949a 100644
--- a/test/test_helper.coffee
+++ b/test/test_helper.coffee
@@ -21,7 +21,7 @@ global.util     = require 'util'
 global.w        = require 'when'
 
 {Logger}      = require 'crafting-guide-common'
-global.logger = new Logger level:Logger.FATAL
+global.logger = new Logger level:Logger.DEBUG
 
 require '../src/coffee/polyfill'
 require '../src/coffee/underscore_mixins'