diff --git a/lib/models/block.js b/lib/models/block.js
index 1db463e8e..be711f12e 100644
--- a/lib/models/block.js
+++ b/lib/models/block.js
@@ -4,7 +4,7 @@ import Inline from './inline'
 import Node from './node'
 import Text from './text'
 import uid from 'uid'
-import Immutable, { Map, OrderedMap, Record } from 'immutable'
+import Immutable, { Map, List, Record } from 'immutable'
 
 /**
  * Default properties.
@@ -13,7 +13,7 @@ import Immutable, { Map, OrderedMap, Record } from 'immutable'
 const DEFAULTS = {
   data: new Map(),
   key: null,
-  nodes: new OrderedMap(),
+  nodes: new List(),
   type: null
 }
 
@@ -38,26 +38,21 @@ class Block extends Record(DEFAULTS) {
 
     properties.key = uid(4)
     properties.data = Data.create(properties.data)
-    properties.nodes = Block.createMap(properties.nodes)
+    properties.nodes = Block.createList(properties.nodes)
 
-    let block = new Block(properties)
-    return block.normalize()
+    return new Block(properties).normalize()
   }
 
   /**
-   * Create an ordered map of `Blocks` from an array of `Blocks`.
+   * Create a list of `Blocks` from an array.
    *
    * @param {Array} elements
-   * @return {OrderedMap} map
+   * @return {List} list
    */
 
-  static createMap(elements = []) {
-    if (OrderedMap.isOrderedMap(elements)) return elements
-    return elements
-      .map(Block.create)
-      .reduce((map, element) => {
-        return map.set(element.key, element)
-      }, new OrderedMap())
+  static createList(elements = []) {
+    if (List.isList(elements)) return elements
+    return new List(elements.map(Block.create))
   }
 
   /**
diff --git a/lib/models/document.js b/lib/models/document.js
index 427163dc8..47bc42653 100644
--- a/lib/models/document.js
+++ b/lib/models/document.js
@@ -26,11 +26,8 @@ class Document extends Record(DEFAULTS) {
 
   static create(properties = {}) {
     if (properties instanceof Document) return properties
-
-    properties.nodes = Block.createMap(properties.nodes)
-
-    let document = new Document(properties)
-    return document.normalize()
+    properties.nodes = Block.createList(properties.nodes)
+    return new Document(properties).normalize()
   }
 
   /**
diff --git a/lib/models/inline.js b/lib/models/inline.js
index 9c72639c8..60bdeb938 100644
--- a/lib/models/inline.js
+++ b/lib/models/inline.js
@@ -4,7 +4,7 @@ import Data from './data'
 import Node from './node'
 import Text from './text'
 import uid from 'uid'
-import Immutable, { Map, OrderedMap, Record } from 'immutable'
+import { List, Map, Record } from 'immutable'
 
 /**
  * Record.
@@ -13,7 +13,7 @@ import Immutable, { Map, OrderedMap, Record } from 'immutable'
 const DEFAULTS = {
   data: new Map(),
   key: null,
-  nodes: new OrderedMap(),
+  nodes: new List(),
   type: null
 }
 
@@ -38,26 +38,22 @@ class Inline extends Record(DEFAULTS) {
 
     properties.key = uid(4)
     properties.data = Data.create(properties.data)
-    properties.nodes = Inline.createMap(properties.nodes)
+    properties.nodes = Inline.createList(properties.nodes)
 
     let inline = new Inline(properties)
     return inline.normalize()
   }
 
   /**
-   * Create an ordered map of `Inlines` from an array of `Inlines`.
+   * Create a list of `Inlines` from an array.
    *
    * @param {Array} elements
-   * @return {OrderedMap} map
+   * @return {List} map
    */
 
-  static createMap(elements = []) {
-    if (OrderedMap.isOrderedMap(elements)) return elements
-    return elements
-      .map(Inline.create)
-      .reduce((map, element) => {
-        return map.set(element.key, element)
-      }, new OrderedMap())
+  static createList(elements = []) {
+    if (List.isList(elements)) return elements
+    return new List(elements.map(Inline.create))
   }
 
   /**
diff --git a/lib/models/mark.js b/lib/models/mark.js
index 34b3f357a..3a39ad081 100644
--- a/lib/models/mark.js
+++ b/lib/models/mark.js
@@ -27,9 +27,7 @@ class Mark extends Record(DEFAULTS) {
   static create(properties = {}) {
     if (properties instanceof Mark) return properties
     if (!properties.type) throw new Error('You must provide a `type` for the mark.')
-
     properties.data = Data.create(properties.data)
-
     return new Mark(properties)
   }
 
diff --git a/lib/models/node.js b/lib/models/node.js
index c558d069b..2ccc7c447 100644
--- a/lib/models/node.js
+++ b/lib/models/node.js
@@ -5,7 +5,7 @@ import Data from './data'
 import Mark from './mark'
 import Selection from './selection'
 import Text from './text'
-import { List, Map, OrderedMap, OrderedSet, Set } from 'immutable'
+import { List, Map, Set } from 'immutable'
 
 /**
  * Node.
@@ -49,9 +49,7 @@ const Node = {
 
     // If the start and end nodes are the same, remove the matching characters.
     if (startKey == endKey) {
-      let { characters } = startNode
-
-      characters = characters.filterNot((char, i) => {
+      const characters = startNode.characters.filterNot((char, i) => {
         return startOffset <= i && i < endOffset
       })
 
@@ -92,7 +90,7 @@ const Node = {
 
     const nodes = node.nodes
       .takeUntil(child => child == startGrandestParent)
-      .set(startGrandestParent.key, startGrandestParent)
+      .push(startGrandestParent)
       .concat(node.nodes.skipUntil(child => child == endGrandestParent))
 
     node = node.merge({ nodes })
@@ -214,17 +212,11 @@ const Node = {
    */
 
   filterDeep(iterator) {
-    return this.nodes.reduce((matches, child) => {
-      if (iterator(child, child.key, this.nodes)) {
-        matches = matches.set(child.key, child)
-      }
-
-      if (child.kind != 'text') {
-        matches = matches.concat(child.filterDeep(iterator))
-      }
-
+    return this.nodes.reduce((matches, child, i, nodes) => {
+      if (iterator(child, i, nodes)) matches = matches.push(child)
+      if (child.kind != 'text') matches = matches.concat(child.filterDeep(iterator))
       return matches
-    }, new OrderedMap())
+    }, Block.createList())
   },
 
   /**
@@ -362,7 +354,8 @@ const Node = {
     key = normalizeKey(key)
     this.assertHasDeep(key)
 
-    if (this.nodes.has(key)) return startAt
+    const shallow = this.nodes.find(node => node.key == key)
+    if (shallow) return startAt
 
     const child = this.nodes.find(node => {
       return node.kind == 'text'
@@ -465,7 +458,8 @@ const Node = {
     key = normalizeKey(key)
     this.assertHasDeep(key)
 
-    if (this.nodes.has(key)) {
+    const shallow = this.nodes.find(node => node.key == key)
+    if (shallow) {
       return this.nodes
         .skipUntil(node => node.key == key)
         .rest()
@@ -526,7 +520,7 @@ const Node = {
 
     // If the child's parent is this node, return the offset of all of the nodes
     // before it, otherwise recurse.
-    return this.nodes.has(match.key)
+    return this.nodes.find(node => node.key == match.key)
       ? offset
       : offset + child.getOffset(key)
   },
@@ -542,7 +536,8 @@ const Node = {
     key = normalizeKey(key)
     // this.assertHasDeep(key)
 
-    if (this.nodes.has(key)) return this
+    const shallow = this.nodes.find(node => node.key == key)
+    if (shallow) return this
 
     let node = null
     this.nodes.forEach((child) => {
@@ -565,7 +560,8 @@ const Node = {
     key = normalizeKey(key)
     this.assertHasDeep(key)
 
-    if (this.nodes.has(key)) {
+    const shallow = this.nodes.find(node => node.key == key)
+    if (shallow) {
       return this.nodes
         .takeUntil(node => node.key == key)
         .last()
@@ -620,9 +616,9 @@ const Node = {
   getTextNodes() {
     return this.nodes.reduce((texts, node) => {
       return node.kind == 'text'
-        ? texts.set(node.key, node)
+        ? texts.push(node)
         : texts.concat(node.getTextNodes())
-    }, new OrderedMap())
+    }, Block.createList())
   },
 
   /**
@@ -648,7 +644,7 @@ const Node = {
     const endNode = this.getDeep(endKey)
     const afterStart = texts.skipUntil(node => node.key == startKey)
     const upToEnd = afterStart.takeUntil(node => node.key == endKey)
-    const matches = upToEnd.set(endNode.key, endNode)
+    const matches = upToEnd.push(endNode)
     return matches
   },
 
@@ -802,18 +798,12 @@ const Node = {
   /**
    * Push a new `node` onto the map of nodes.
    *
-   * @param {String or Node} key
-   * @param {Node} node (optional)
+   * @param {Node} node
    * @return {Node} node
    */
 
-  pushNode(key, node) {
-    if (arguments.length == 1) {
-      node = key
-      key = normalizeKey(key)
-    }
-
-    let nodes = this.nodes.set(key, node)
+  pushNode(node) {
+    const nodes = this.nodes.push(node)
     return this.merge({ nodes })
   },
 
@@ -827,8 +817,7 @@ const Node = {
   removeDeep(key) {
     key = normalizeKey(key)
     this.assertHasDeep(key)
-
-    let nodes = this.nodes.remove(key)
+    const nodes = this.nodes.filterNot(node => node.key == key)
     return this.merge({ nodes })
   },
 
@@ -943,8 +932,8 @@ const Node = {
     // Replace the block in the parent with the two new blocks.
     let parent = node.getParent(firstBlock)
     const nodes = parent.nodes.takeUntil(n => n.key == firstBlock.key)
-      .set(firstBlock.key, firstBlock)
-      .set(secondBlock.key, secondBlock)
+      .push(firstBlock)
+      .push(secondBlock)
       .concat(parent.nodes.skipUntil(n => n.key == firstBlock.key).rest())
 
     // If the node is the parent, just merge, otherwise deep merge.
@@ -960,7 +949,6 @@ const Node = {
   },
 
   splitInlineAtRange(range) {
-    debugger
     range = range.normalize(this)
     const Inline = require('./inline').default
     let node = this
@@ -979,7 +967,7 @@ const Node = {
 
     // While the parent is an inline parent, split the inline nodes.
     while (parent = node.getClosestInline(firstChild)) {
-      firstChild = parent.merge({ nodes: Inline.createMap([firstChild]) })
+      firstChild = parent.merge({ nodes: Inline.createList([firstChild]) })
       secondChild = Inline.create({
         nodes: [secondChild],
         type: parent.type,
@@ -987,16 +975,15 @@ const Node = {
       })
 
       // Split the children.
-      const isGrandparent = node.nodes.has(parent.key)
-      const grandparent = isGrandparent ? node : node.getParent(parent)
+      const grandparent = node.getParent(parent)
       const nodes = grandparent.nodes
         .takeUntil(c => c.key == firstChild.key)
-        .set(firstChild.key, firstChild)
-        .set(secondChild.key, secondChild)
+        .push(firstChild)
+        .push(secondChild)
         .concat(grandparent.nodes.skipUntil(n => n.key == firstChild.key).rest())
 
       // Update the grandparent.
-      node = isGrandparent
+      node = grandparent == node
         ? node.merge({ nodes })
         : node.updateDeep(grandparent.merge({ nodes }))
     }
@@ -1034,8 +1021,8 @@ const Node = {
     let parent = node.getParent(text)
     const nodes = parent.nodes
       .takeUntil(c => c.key == firstChild.key)
-      .set(firstChild.key, firstChild)
-      .set(secondChild.key, secondChild)
+      .push(firstChild)
+      .push(secondChild)
       .concat(parent.nodes.skipUntil(n => n.key == firstChild.key).rest())
 
     // Update the nodes.
@@ -1090,26 +1077,21 @@ const Node = {
   /**
    * Set a new value for a child node by `key`.
    *
-   * @param {String or Node} key
-   * @param {Node} node (optional)
+   * @param {Node} node
    * @return {Node} node
    */
 
-  updateDeep(key, node) {
-    if (arguments.length == 1) {
-      node = key
-      key = normalizeKey(key)
-    }
-
+  updateDeep(node) {
     // this.assertHasDeep(key)
 
-    if (this.nodes.get(key)) {
-      const nodes = this.nodes.set(key, node)
-      return this.set('nodes', nodes)
+    const shallow = this.nodes.find(child => child.key == node.key)
+    if (shallow) {
+      const nodes = this.nodes.map(child => child.key == node.key ? node : child)
+      return this.merge({ nodes })
     }
 
     const nodes = this.nodes.map((child) => {
-      return child.kind == 'text' ? child : child.updateDeep(key, node)
+      return child.kind == 'text' ? child : child.updateDeep(node)
     })
 
     return this.merge({ nodes })
@@ -1146,9 +1128,9 @@ const Node = {
       const sibling = node.getDepth(block) == depth
         ? block
         : node.getClosest(block, (p) => node.getDepth(p) == depth)
-      siblings = siblings.set(sibling.key, sibling)
+      siblings = siblings.push(sibling)
       return siblings
-    }, new OrderedMap())
+    }, Block.createList())
 
     // Wrap the siblings in a new block.
     const wrapper = Block.create({
@@ -1158,20 +1140,16 @@ const Node = {
     })
 
     // Replace the siblings with the wrapper.
-    const isDirectChild = node.nodes.has(highest.key)
-    let parent = isDirectChild ? node : node.getParent(highest)
+    const parent = node.getParent(highest)
     const nodes = parent.nodes
       .takeUntil(node => node == highest)
-      .set(wrapper.key, wrapper)
+      .push(wrapper)
       .concat(parent.nodes.skipUntil(node => node == highest).rest())
 
     // Update the parent.
-    if (isDirectChild) {
-      node = node.merge({ nodes })
-    } else {
-      parent = parent.merge({ nodes })
-      node = node.updateDeep(parent)
-    }
+    node = parent == node
+      ? node.merge({ nodes })
+      : node.updateDeep(parent.merge({ nodes }))
 
     return node
   },
@@ -1208,14 +1186,13 @@ const Node = {
         return true
       })
 
-      if (match) wrappers = wrappers.set(match.key, match)
+      if (match) wrappers = wrappers.add(match)
       return wrappers
-    }, new OrderedMap())
+    }, new Set())
 
     // Replace each of the wrappers with their child nodes.
     wrappers.forEach((wrapper) => {
-      const isDirectChild = node.nodes.has(wrapper.key)
-      let parent = isDirectChild ? node : node.getParent(wrapper)
+      const parent = node.getParent(wrapper)
 
       // Replace the wrapper in the parent's nodes with the block.
       const nodes = parent.nodes.takeUntil(n => n == wrapper)
@@ -1223,12 +1200,9 @@ const Node = {
         .concat(parent.nodes.skipUntil(n => n == wrapper).rest())
 
       // Update the parent.
-      if (isDirectChild) {
-        node = node.merge({ nodes })
-      } else {
-        parent = parent.merge({ nodes })
-        node = node.updateDeep(parent)
-      }
+      node = parent == node
+        ? node.merge({ nodes })
+        : node.updateDeep(parent.merge({ nodes }))
     })
 
     return node.normalize()
@@ -1298,7 +1272,7 @@ const Node = {
       // Replace the child in it's parent with the wrapper.
       const parent = node.getParent(child)
       const nodes = parent.nodes.takeUntil(n => n == child)
-        .set(wrapper.key, wrapper)
+        .push(wrapper)
         .concat(parent.nodes.skipUntil(n => n == child).rest())
 
       // Update the parent.
@@ -1343,14 +1317,13 @@ const Node = {
         return true
       })
 
-      if (match) wrappers = wrappers.set(match.key, match)
+      if (match) wrappers = wrappers.add(match)
       return wrappers
-    }, new OrderedMap())
+    }, new Set())
 
     // Replace each of the wrappers with their child nodes.
     wrappers.forEach((wrapper) => {
       const parent = node.getParent(wrapper)
-      const isDirectChild = parent == node
 
       // Replace the wrapper in the parent's nodes with the block.
       const nodes = parent.nodes.takeUntil(n => n == wrapper)
@@ -1358,7 +1331,7 @@ const Node = {
         .concat(parent.nodes.skipUntil(n => n == wrapper).rest())
 
       // Update the parent.
-      node = isDirectChild
+      node = parent == node
         ? node.merge({ nodes })
         : node.updateDeep(parent.merge({ nodes }))
     })
diff --git a/lib/models/state.js b/lib/models/state.js
index 9ad5cd5f4..7cbbd9f29 100644
--- a/lib/models/state.js
+++ b/lib/models/state.js
@@ -60,10 +60,8 @@ class State extends Record(DEFAULTS) {
 
   static create(properties = {}) {
     if (properties instanceof State) return properties
-
     properties.document = Document.create(properties.document)
     properties.selection = Selection.create(properties.selection)
-
     return new State(properties)
   }
 
diff --git a/lib/models/text.js b/lib/models/text.js
index 0ba88392d..a779467f3 100644
--- a/lib/models/text.js
+++ b/lib/models/text.js
@@ -27,10 +27,8 @@ class Text extends Record(DEFAULTS) {
 
   static create(properties = {}) {
     if (properties instanceof Text) return properties
-
     properties.key = uid(4)
     properties.characters = Character.createList(properties.characters)
-
     return new Text(properties)
   }
 
diff --git a/lib/serializers/raw.js b/lib/serializers/raw.js
index 0508e698c..0f574f02c 100644
--- a/lib/serializers/raw.js
+++ b/lib/serializers/raw.js
@@ -94,7 +94,7 @@ function serializeMark(mark) {
 function deserialize(object) {
   return State.create({
     document: Document.create({
-      nodes: Block.createMap(object.nodes.map(deserializeNode))
+      nodes: Block.createList(object.nodes.map(deserializeNode))
     })
   })
 }
@@ -111,15 +111,15 @@ function deserializeNode(object) {
     case 'block': {
       return Block.create({
         type: object.type,
-        data: new Map(object.data),
-        nodes: Block.createMap(object.nodes.map(deserializeNode))
+        data: object.data,
+        nodes: Block.createList(object.nodes.map(deserializeNode))
       })
     }
     case 'inline': {
       return Inline.create({
         type: object.type,
-        data: new Map(object.data),
-        nodes: Inline.createMap(object.nodes.map(deserializeNode))
+        data: object.data,
+        nodes: Inline.createList(object.nodes.map(deserializeNode))
       })
     }
     case 'text': {
@@ -161,10 +161,7 @@ function deserializeRanges(array) {
  */
 
 function deserializeMark(object) {
-  return Mark.create({
-    type: object.type,
-    data: new Map(object.data)
-  })
+  return Mark.create(object)
 }
 
 /**
diff --git a/package.json b/package.json
index 443b2aaed..40c3cc5ee 100644
--- a/package.json
+++ b/package.json
@@ -25,6 +25,7 @@
     "mocha-phantomjs": "^4.0.2",
     "react-dom": "^15.1.0",
     "read-metadata": "^1.0.0",
+    "source-map-support": "^0.4.0",
     "standard": "^7.1.2",
     "to-camel-case": "^1.0.0",
     "watchify": "^3.7.0"
diff --git a/test/server/index.js b/test/server/index.js
index f36494c7b..e7fb3a1bc 100644
--- a/test/server/index.js
+++ b/test/server/index.js
@@ -1,2 +1,3 @@
 
+import 'source-map-support/register'
 import './transforms'