diff --git a/.eslintrc b/.eslintrc
index d0456bf30..e500b31b1 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -18,7 +18,10 @@
     "node": true
   },
   "rules": {
+    "arrow-parens": ["error", "as-needed", { "requireForBlockBody": true }],
+    "arrow-spacing": "error",
     "block-spacing": "error",
+    "capitalized-comments": ["error", "always", { "ignoreConsecutiveComments": true }],
     "comma-dangle": ["error", "only-multiline"],
     "comma-spacing": ["error", { "before": false, "after": true }],
     "comma-style": ["error", "last"],
@@ -28,8 +31,12 @@
     "dot-location": ["error", "property"],
     "dot-notation": ["error", { "allowKeywords": true }],
     "eol-last": "error",
+    "func-call-spacing": ["error", "never"],
     "func-style": ["error", "declaration"],
+    "import/default": "error",
     "import/export": "error",
+    "import/first": "error",
+    "import/named": "error",
     "import/namespace": "error",
     "import/newline-after-import": "error",
     "import/no-deprecated": "error",
@@ -39,8 +46,11 @@
     "import/no-named-as-default-member": "error",
     "import/no-unresolved": "error",
     "indent": ["error", 2, { "SwitchCase": 1, "MemberExpression": 1 }],
+    "jsx-quotes": ["error", "prefer-double"],
     "key-spacing": ["error", { "beforeColon": false, "afterColon": true }],
-    "lines-around-comment": ["error", { "beforeBlockComment": true, "afterBlockComment": true }],
+    "keyword-spacing": ["error", { "before": true, "after": true }],
+    "linebreak-style": "error",
+    "lines-around-comment": ["error", { "beforeBlockComment": true, "afterBlockComment": true, "allowBlockStart": true, "allowObjectStart": true, "allowArrayStart": true }],
     "new-parens": "error",
     "no-array-constructor": "error",
     "no-class-assign": "error",
@@ -56,8 +66,10 @@
     "no-empty-pattern": "error",
     "no-ex-assign": "error",
     "no-extend-native": "error",
+    "no-extra-boolean-cast": "error",
     "no-func-assign": "error",
     "no-invalid-regexp": "error",
+    "no-lonely-if": "error",
     "no-mixed-spaces-and-tabs": ["error", false],
     "no-multi-spaces": "error",
     "no-multiple-empty-lines": ["error", { "max": 2, "maxEOF": 1 }],
@@ -65,19 +77,24 @@
     "no-negated-in-lhs": "error",
     "no-new-object": "error",
     "no-new-symbol": "error",
+    "no-path-concat": "error",
     "no-redeclare": "error",
     "no-regex-spaces": "error",
     "no-sequences": "error",
     "no-shadow": "error",
     "no-shadow-restricted-names": "error",
     "no-spaced-func": "error",
+    "no-tabs": "error",
+    "no-this-before-super": "error",
     "no-throw-literal": "error",
     "no-trailing-spaces": "error",
     "no-undef": "error",
+    "no-unneeded-ternary": "error",
     "no-unreachable": "error",
     "no-unsafe-finally": "error",
+    "no-unsafe-negation": "error",
     "no-unused-expressions": "error",
-    "no-unused-vars": ["warn", { "vars": "all", "args": "none" }],
+    "no-unused-vars": ["error", { "vars": "all", "args": "none" }],
     "no-useless-call": "error",
     "no-useless-computed-key": "error",
     "no-useless-constructor": "error",
@@ -86,12 +103,17 @@
     "no-void": "error",
     "no-whitespace-before-property": "error",
     "no-with": "error",
+    "object-curly-spacing": ["error", "always", { "objectsInObjects": false }],
     "object-property-newline": ["error", { "allowMultiplePropertiesPerLine": true }],
     "object-shorthand": ["error", "always"],
+    "operator-linebreak": ["error", "after", { "overrides": { "?": "ignore", ":": "ignore" }}],
+    "padded-blocks": ["error", { "blocks": "never", "classes": "always" }],
     "prefer-arrow-callback": "error",
+    "prefer-const": ["error", { "destructuring": "all", "ignoreReadBeforeAssign": true }],
     "prefer-rest-params": "error",
     "prefer-spread": "error",
     "prefer-template": "error",
+    "quotes": ["error", "single", { "allowTemplateLiterals": true }],
     "radix": "error",
     "react/jsx-boolean-value": ["error", "never"],
     "react/jsx-closing-bracket-location": "error",
@@ -101,6 +123,7 @@
     "react/jsx-key": "error",
     "react/jsx-no-bind": "error",
     "react/jsx-no-duplicate-props": "error",
+    "react/jsx-no-target-blank": "error",
     "react/jsx-no-undef": "error",
     "react/jsx-space-before-closing": ["error", "always"],
     "react/jsx-uses-react": "error",
@@ -123,6 +146,7 @@
     "space-unary-ops": ["error", { "words": true, "nonwords": false }],
     "spaced-comment": ["error", "always", { "exceptions": ["-"]}],
     "template-curly-spacing": "error",
+    "template-tag-spacing": ["error", "never"],
     "unicode-bom": ["error", "never"],
     "use-isnan": "error",
     "valid-jsdoc": ["error", { "prefer": { "return": "returns" }, "requireReturn": false }],
diff --git a/examples/auto-markdown/index.js b/examples/auto-markdown/index.js
index bc6babcce..5c10686ee 100644
--- a/examples/auto-markdown/index.js
+++ b/examples/auto-markdown/index.js
@@ -130,7 +130,7 @@ class AutoMarkdown extends React.Component {
     if (type == 'list-item' && startBlock.type == 'list-item') return
     e.preventDefault()
 
-    let transform = state
+    const transform = state
       .transform()
       .setBlock(type)
 
@@ -161,7 +161,7 @@ class AutoMarkdown extends React.Component {
     if (startBlock.type == 'paragraph') return
     e.preventDefault()
 
-    let transform = state
+    const transform = state
       .transform()
       .setBlock('paragraph')
 
diff --git a/examples/code-highlighting/index.js b/examples/code-highlighting/index.js
index e46fc89bd..6ec28a58a 100644
--- a/examples/code-highlighting/index.js
+++ b/examples/code-highlighting/index.js
@@ -153,7 +153,7 @@ class CodeHighlighting extends React.Component {
     const { startBlock } = state
     if (startBlock.type != 'code') return
 
-    let transform = state.transform()
+    const transform = state.transform()
     if (state.isExpanded) transform.delete()
     transform.insertText('\n')
 
diff --git a/examples/development/performance-rich/index.js b/examples/development/performance-rich/index.js
index b807f640e..923f31a7e 100644
--- a/examples/development/performance-rich/index.js
+++ b/examples/development/performance-rich/index.js
@@ -166,7 +166,7 @@ class RichText extends React.Component {
     const isActive = this.hasBlock(type)
     let { state } = this.state
 
-    let transform = state
+    const transform = state
       .transform()
       .setBlock(isActive ? 'paragraph' : type)
 
diff --git a/examples/hovering-menu/index.js b/examples/hovering-menu/index.js
index 7f9ed51f7..349544c4a 100644
--- a/examples/hovering-menu/index.js
+++ b/examples/hovering-menu/index.js
@@ -2,8 +2,8 @@
 import { Editor, Raw } from '../..'
 import Portal from 'react-portal'
 import React from 'react'
-import position from 'selection-position'
 import initialState from './state.json'
+import position from 'selection-position'
 
 /**
  * Define a schema.
diff --git a/examples/links/index.js b/examples/links/index.js
index bdd96be71..41f9b1a03 100644
--- a/examples/links/index.js
+++ b/examples/links/index.js
@@ -122,7 +122,7 @@ class Links extends React.Component {
     if (data.type != 'text' && data.type != 'html') return
     if (!isUrl(data.text)) return
 
-    let transform = state.transform()
+    const transform = state.transform()
 
     if (this.hasLinks()) {
       transform.unwrapInline('link')
diff --git a/examples/rich-text/index.js b/examples/rich-text/index.js
index 3b96ad8fa..429b0255e 100644
--- a/examples/rich-text/index.js
+++ b/examples/rich-text/index.js
@@ -163,7 +163,7 @@ class RichText extends React.Component {
   onClickBlock = (e, type) => {
     e.preventDefault()
     let { state } = this.state
-    let transform = state.transform()
+    const transform = state.transform()
     const { document } = state
 
     // Handle everything but list buttons.
diff --git a/examples/rtl/index.js b/examples/rtl/index.js
index 787d3243a..acea684bb 100644
--- a/examples/rtl/index.js
+++ b/examples/rtl/index.js
@@ -11,7 +11,7 @@ import initialState from './state.json'
 
 const schema = {
   nodes: {
-    'block-quote': (props) => <blockquote {...props.attributes}>{props.children}</blockquote>,
+    'block-quote': props => <blockquote {...props.attributes}>{props.children}</blockquote>,
   }
 }
 
diff --git a/src/components/content.js b/src/components/content.js
index 1ab67dea1..0b41de657 100644
--- a/src/components/content.js
+++ b/src/components/content.js
@@ -402,9 +402,8 @@ class Content extends React.Component {
       range.setStart(nativeEvent.rangeParent, nativeEvent.rangeOffset)
     }
 
-    const startNode = range.startContainer
-    const startOffset = range.startOffset
-    const point = this.getPoint(startNode, startOffset)
+    const { startContainer, startOffset } = range
+    const point = this.getPoint(startContainer, startOffset)
     if (!point) return
 
     const target = Selection.create({
@@ -616,7 +615,7 @@ class Content extends React.Component {
 
     const window = getWindow(event.target)
     const { state } = this.props
-    let { document, selection } = state
+    const { document, selection } = state
     const native = window.getSelection()
     const data = {}
 
@@ -704,7 +703,7 @@ class Content extends React.Component {
       .map(node => this.renderNode(node))
       .toArray()
 
-    let style = {
+    const style = {
       // Prevent the default outline styles.
       outline: 'none',
       // Preserve adjacent whitespace and new lines.
diff --git a/src/components/leaf.js b/src/components/leaf.js
index 2cd13c715..4ac8c3df0 100644
--- a/src/components/leaf.js
+++ b/src/components/leaf.js
@@ -166,43 +166,40 @@ class Leaf extends React.Component {
     }
 
     // Otherwise we need to set the selection across two different leaves.
-    else {
-      // If the selection is forward, we can set things in sequence. In the
-      // first leaf to render, reset the selection and set the new start. And
-      // then in the second leaf to render, extend to the new end.
-      if (selection.isForward) {
-        if (hasAnchor) {
-          native.removeAllRanges()
-          const range = window.document.createRange()
-          range.setStart(el, anchorOffset)
-          native.addRange(range)
-        } else if (hasFocus) {
-          native.extend(el, focusOffset)
-          focus()
-        }
+    // If the selection is forward, we can set things in sequence. In the
+    // first leaf to render, reset the selection and set the new start. And
+    // then in the second leaf to render, extend to the new end.
+    else if (selection.isForward) {
+      if (hasAnchor) {
+        native.removeAllRanges()
+        const range = window.document.createRange()
+        range.setStart(el, anchorOffset)
+        native.addRange(range)
+      } else if (hasFocus) {
+        native.extend(el, focusOffset)
+        focus()
       }
+    }
 
-      // Otherwise, if the selection is backward, we need to hack the order a bit.
-      // In the first leaf to render, set a phony start anchor to store the true
-      // end position. And then in the second leaf to render, set the start and
-      // extend the end to the stored value.
-      else {
-        if (hasFocus) {
-          native.removeAllRanges()
-          const range = window.document.createRange()
-          range.setStart(el, focusOffset)
-          native.addRange(range)
-        } else if (hasAnchor) {
-          const endNode = native.focusNode
-          const endOffset = native.focusOffset
-          native.removeAllRanges()
-          const range = window.document.createRange()
-          range.setStart(el, anchorOffset)
-          native.addRange(range)
-          native.extend(endNode, endOffset)
-          focus()
-        }
-      }
+    // Otherwise, if the selection is backward, we need to hack the order a bit.
+    // In the first leaf to render, set a phony start anchor to store the true
+    // end position. And then in the second leaf to render, set the start and
+    // extend the end to the stored value.
+    else if (hasFocus) {
+      native.removeAllRanges()
+      const range = window.document.createRange()
+      range.setStart(el, focusOffset)
+      native.addRange(range)
+    }
+    else if (hasAnchor) {
+      const endNode = native.focusNode
+      const endOffset = native.focusOffset
+      native.removeAllRanges()
+      const range = window.document.createRange()
+      range.setStart(el, anchorOffset)
+      native.addRange(range)
+      native.extend(endNode, endOffset)
+      focus()
     }
 
     this.debug('updateSelection', { selection })
@@ -305,6 +302,7 @@ class Leaf extends React.Component {
       )
     }, children)
   }
+
 }
 
 /**
diff --git a/src/components/node.js b/src/components/node.js
index 841ec2666..47f4d7a6f 100644
--- a/src/components/node.js
+++ b/src/components/node.js
@@ -62,7 +62,7 @@ class Node extends React.Component {
   debug = (message, ...args) => {
     const { node } = this.props
     const { key, kind, type } = node
-    let id = kind == 'text' ? `${key} (${kind})` : `${key} (${type})`
+    const id = kind == 'text' ? `${key} (${kind})` : `${key} (${type})`
     debug(message, `${id}`, ...args)
   }
 
@@ -349,8 +349,7 @@ class Node extends React.Component {
 
   renderLeaf = (ranges, range, index, offset) => {
     const { node, parent, schema, state, editor } = this.props
-    const text = range.text
-    const marks = range.marks
+    const { text, marks } = range
 
     return (
       <Leaf
diff --git a/src/components/placeholder.js b/src/components/placeholder.js
index 7e081fe29..019a01886 100644
--- a/src/components/placeholder.js
+++ b/src/components/placeholder.js
@@ -73,7 +73,7 @@ class Placeholder extends React.Component {
     let { style } = this.props
 
     if (typeof children === 'string' && style == null && className == null) {
-      style = { opacity: '0.333'}
+      style = { opacity: '0.333' }
     } else if (style == null) {
       style = {}
     }
diff --git a/src/components/void.js b/src/components/void.js
index c7277cdac..b66eda0a4 100644
--- a/src/components/void.js
+++ b/src/components/void.js
@@ -47,7 +47,7 @@ class Void extends React.Component {
   debug = (message, ...args) => {
     const { node } = this.props
     const { key, type } = node
-    let id = `${key} (${type})`
+    const id = `${key} (${type})`
     debug(message, `${id}`, ...args)
   }
 
diff --git a/src/models/character.js b/src/models/character.js
index 507e5ece7..b3dd5d644 100644
--- a/src/models/character.js
+++ b/src/models/character.js
@@ -55,7 +55,7 @@ class Character extends new Record(DEFAULTS) {
    */
 
   static createListFromText(string, marks) {
-    const chars = string.split('').map(text => { return { text, marks } })
+    const chars = string.split('').map((text) => { return { text, marks } })
     const list = Character.createList(chars)
     return list
   }
diff --git a/src/models/node.js b/src/models/node.js
index a082443fe..02ef76770 100644
--- a/src/models/node.js
+++ b/src/models/node.js
@@ -30,7 +30,7 @@ const Node = {
   getKeys() {
     const keys = []
 
-    this.forEachDescendant(desc => {
+    this.forEachDescendant((desc) => {
       keys.push(desc.key)
     })
 
@@ -160,7 +160,7 @@ const Node = {
 
     let descendantFound = null
 
-    this.nodes.find(node => {
+    this.nodes.find((node) => {
       if (node.kind != 'text') {
         descendantFound = node.findDescendant(iterator)
         return descendantFound
@@ -182,7 +182,7 @@ const Node = {
   findDescendantDeep(iterator) {
     let found
 
-    this.forEachDescendant(node => {
+    this.forEachDescendant((node) => {
       if (iterator(node)) {
         found = node
         return false
@@ -339,7 +339,7 @@ const Node = {
 
   getClosest(key, iterator) {
     key = Normalize.key(key)
-    let ancestors = this.getAncestors(key)
+    const ancestors = this.getAncestors(key)
     if (!ancestors) {
       throw new Error(`Could not find a descendant node with key "${key}".`)
     }
@@ -478,7 +478,7 @@ const Node = {
   _getDescendant(key) {
     let descendantFound = null
 
-    const found = this.nodes.find(node => {
+    const found = this.nodes.find((node) => {
       if (node.key === key) {
         return node
       } else if (node.kind !== 'text') {
@@ -526,7 +526,7 @@ const Node = {
 
     let sorted
 
-    this.forEachDescendant(n => {
+    this.forEachDescendant((n) => {
       if (n.key === key1) {
         sorted = true
         return false
@@ -606,7 +606,7 @@ const Node = {
    */
 
   getFurthest(key, iterator) {
-    let ancestors = this.getAncestors(key)
+    const ancestors = this.getAncestors(key)
     if (!ancestors) {
       key = Normalize.key(key)
       throw new Error(`Could not find a descendant node with key "${key}".`)
@@ -647,7 +647,7 @@ const Node = {
 
   getHighestChild(key) {
     key = Normalize.key(key)
-    return this.nodes.find(node => {
+    return this.nodes.find((node) => {
       if (node.key == key) return true
       if (node.kind == 'text') return false
       return node.hasDescendant(key)
@@ -890,7 +890,7 @@ const Node = {
 
     if (key == this.key) return []
 
-    let path = []
+    const path = []
     let childKey = key
     let parent
 
@@ -1024,11 +1024,8 @@ const Node = {
    */
 
   getTextDirection() {
-    const text = this.text
-    const dir = direction(text)
-    return dir == 'neutral'
-      ? undefined
-      : dir
+    const dir = direction(this.text)
+    return dir == 'neutral' ? undefined : dir
   },
 
   /**
@@ -1160,7 +1157,7 @@ const Node = {
    */
 
   insertNode(index, node) {
-    let keys = this.getKeys()
+    const keys = this.getKeys()
 
     if (keys.contains(node.key)) {
       node = node.regenerateKey()
@@ -1220,7 +1217,7 @@ const Node = {
     }
 
     else {
-      const size = first.nodes.size
+      const { size } = first.nodes
       second.nodes.forEach((child, i) => {
         first = first.insertNode(size + i, child)
       })
@@ -1246,10 +1243,10 @@ const Node = {
    */
 
   mapChildren(iterator) {
-    let nodes = this.nodes
+    let { nodes } = this
 
     nodes.forEach((node, i) => {
-      let ret = iterator(node, i, this.nodes)
+      const ret = iterator(node, i, this.nodes)
       if (ret != node) nodes = nodes.set(ret.key, ret)
     })
 
@@ -1265,7 +1262,7 @@ const Node = {
    */
 
   mapDescendants(iterator) {
-    let nodes = this.nodes
+    let { nodes } = this
 
     nodes.forEach((node, i) => {
       let ret = node
@@ -1338,7 +1335,7 @@ const Node = {
 
   splitNode(path, offset) {
     let base = this
-    let node = base.assertPath(path)
+    const node = base.assertPath(path)
     let parent = base.getParent(node.key)
     const isParent = base == parent
     const index = parent.nodes.indexOf(node)
@@ -1396,7 +1393,7 @@ const Node = {
 
   splitNodeAfter(path, count) {
     let base = this
-    let node = base.assertPath(path)
+    const node = base.assertPath(path)
     if (node.kind === 'text') throw new Error('Cannot split text node at index. Use Node.splitNode at offset instead')
     const { nodes } = node
 
@@ -1429,7 +1426,7 @@ const Node = {
 
   splitBlockAtRange(range, height = 1) {
     const { startKey, startOffset } = range
-    let base = this
+    const base = this
     let node = base.assertDescendant(startKey)
     let parent = base.getClosestBlock(node.key)
     let offset = startOffset
@@ -1456,7 +1453,7 @@ const Node = {
   updateDescendant(node) {
     let found = false
 
-    const result = this.mapDescendants(d => {
+    const result = this.mapDescendants((d) => {
       if (d.key == node.key) {
         found = true
         return node
diff --git a/src/models/range.js b/src/models/range.js
index 9606877f6..f3220a9fc 100644
--- a/src/models/range.js
+++ b/src/models/range.js
@@ -64,6 +64,7 @@ class Range extends new Record(DEFAULTS) {
         })
       }))
   }
+
 }
 
 /**
diff --git a/src/models/selection.js b/src/models/selection.js
index 9a00cd5ff..3675c9735 100644
--- a/src/models/selection.js
+++ b/src/models/selection.js
@@ -295,7 +295,7 @@ class Selection extends new Record(DEFAULTS) {
    */
 
   normalize(node) {
-    let selection = this
+    const selection = this
     let { anchorKey, anchorOffset, focusKey, focusOffset, isBackward } = selection
 
     // If the selection isn't formed yet or is malformed, ensure that it is
@@ -322,8 +322,8 @@ class Selection extends new Record(DEFAULTS) {
     // If the anchor node isn't a text node, match it to one.
     if (anchorNode.kind != 'text') {
       warn('The selection anchor was set to a Node that is not a Text node. This should not happen and can degrade performance. The node in question was:', anchorNode)
-      let anchorText = anchorNode.getTextAtOffset(anchorOffset)
-      let offset = anchorNode.getOffset(anchorText.key)
+      const anchorText = anchorNode.getTextAtOffset(anchorOffset)
+      const offset = anchorNode.getOffset(anchorText.key)
       anchorOffset = anchorOffset - offset
       anchorNode = anchorText
     }
@@ -331,8 +331,8 @@ class Selection extends new Record(DEFAULTS) {
     // If the focus node isn't a text node, match it to one.
     if (focusNode.kind != 'text') {
       warn('The selection focus was set to a Node that is not a Text node. This should not happen and can degrade performance. The node in question was:', focusNode)
-      let focusText = focusNode.getTextAtOffset(focusOffset)
-      let offset = focusNode.getOffset(focusText.key)
+      const focusText = focusNode.getTextAtOffset(focusOffset)
+      const offset = focusNode.getOffset(focusText.key)
       focusOffset = focusOffset - offset
       focusNode = focusText
     }
diff --git a/src/models/state.js b/src/models/state.js
index 5d9d3d88b..4243f10dc 100644
--- a/src/models/state.js
+++ b/src/models/state.js
@@ -48,7 +48,7 @@ class State extends new Record(DEFAULTS) {
   static create(properties = {}) {
     if (properties instanceof State) return properties
 
-    let document = Document.create(properties.document)
+    const document = Document.create(properties.document)
     let selection = Selection.create(properties.selection)
 
     if (selection.isUnset) {
diff --git a/src/models/text.js b/src/models/text.js
index 111ba4efd..ca119d588 100644
--- a/src/models/text.js
+++ b/src/models/text.js
@@ -212,7 +212,7 @@ class Text extends new Record(DEFAULTS) {
 
   getRanges(decorators = []) {
     const list = new List()
-    let characters = this.getDecorations(decorators)
+    const characters = this.getDecorations(decorators)
 
     // If there are no characters, return one empty range.
     if (characters.size == 0) {
@@ -327,8 +327,8 @@ class Text extends new Record(DEFAULTS) {
 
   removeText(index, length) {
     let { characters } = this
-    let start = index
-    let end = index + length
+    const start = index
+    const end = index + length
     characters = characters.filterNot((char, i) => start <= i && i < end)
     return this.merge({ characters })
   }
diff --git a/src/models/transform.js b/src/models/transform.js
index 73623178c..fb0b3634f 100644
--- a/src/models/transform.js
+++ b/src/models/transform.js
@@ -52,15 +52,15 @@ class Transform {
    */
 
   apply(options = {}) {
-    let transform = this
+    const transform = this
     let { merge, save, isNative = false } = options
 
     // Ensure that the selection is normalized.
     transform.normalizeSelection()
 
-    let { state, operations } = transform
-    let { history } = state
-    let { undos } = history
+    const { state, operations } = transform
+    const { history } = state
+    const { undos } = history
     const previous = undos.peek()
 
     // If there are no operations, abort early.
diff --git a/src/plugins/core.js b/src/plugins/core.js
index e079c74b0..670887ebd 100644
--- a/src/plugins/core.js
+++ b/src/plugins/core.js
@@ -317,7 +317,7 @@ function Plugin(options = {}) {
         : selection.endOffset)
     }
 
-    let transform = state.transform()
+    const transform = state.transform()
 
     if (isInternal) transform.delete()
 
@@ -340,7 +340,7 @@ function Plugin(options = {}) {
     debug('onDropText', { data })
 
     const { text, target } = data
-    let transform = state
+    const transform = state
       .transform()
       .moveTo(target)
 
@@ -784,7 +784,7 @@ function Plugin(options = {}) {
   function onPasteText(e, data, state) {
     debug('onPasteText', { data })
 
-    let transform = state.transform()
+    const transform = state.transform()
 
     data.text
       .split('\n')
@@ -836,9 +836,9 @@ function Plugin(options = {}) {
                 state={props.state}
                 style={placeholderStyle}
               >
-              {placeholder}
-            </Placeholder>
-           : null}
+                {placeholder}
+              </Placeholder>
+            : null}
         </div>
       )
     }
diff --git a/src/schemas/core.js b/src/schemas/core.js
index 9746428b5..ea0f3ae87 100644
--- a/src/schemas/core.js
+++ b/src/schemas/core.js
@@ -126,7 +126,7 @@ const rules = [
 
       transform.insertNodeByKey(node.key, index, text, OPTS)
 
-      node.nodes.forEach(child => {
+      node.nodes.forEach((child) => {
         transform.removeNodeByKey(child.key, OPTS)
       })
     }
diff --git a/src/transforms/apply-operation.js b/src/transforms/apply-operation.js
index c2b84e010..97be5762c 100644
--- a/src/transforms/apply-operation.js
+++ b/src/transforms/apply-operation.js
@@ -43,7 +43,7 @@ const OPERATIONS = {
  */
 
 export function applyOperation(transform, operation) {
-  let { state, operations } = transform
+  const { state, operations } = transform
   const { type } = operation
   const fn = OPERATIONS[type]
 
@@ -260,7 +260,6 @@ function removeNode(state, operation) {
         selection = selection.unset()
       }
     }
-
   }
 
   // Remove the node from the document.
@@ -362,7 +361,7 @@ function setNode(state, operation) {
  */
 
 function setSelection(state, operation) {
-  let properties = { ...operation.properties }
+  const properties = { ...operation.properties }
   let { document, selection } = state
 
   if (properties.anchorPath !== undefined) {
diff --git a/src/transforms/at-current-range.js b/src/transforms/at-current-range.js
index 615f380bc..77aa01fa3 100644
--- a/src/transforms/at-current-range.js
+++ b/src/transforms/at-current-range.js
@@ -289,8 +289,8 @@ export function setInline(transform, properties) {
  */
 
 export function splitBlock(transform, depth = 1) {
-  let { state } = transform
-  let { selection } = state
+  const { state } = transform
+  const { selection } = state
   transform
     .snapshotSelection()
     .splitBlockAtRange(selection, depth)
@@ -306,8 +306,8 @@ export function splitBlock(transform, depth = 1) {
  */
 
 export function splitInline(transform, depth = Infinity) {
-  let { state } = transform
-  let { selection } = state
+  const { state } = transform
+  const { selection } = state
   transform
     .snapshotSelection()
     .splitInlineAtRange(selection, depth)
diff --git a/src/transforms/at-range.js b/src/transforms/at-range.js
index c58e9ce71..2c0c98f94 100644
--- a/src/transforms/at-range.js
+++ b/src/transforms/at-range.js
@@ -94,7 +94,7 @@ export function deleteAtRange(transform, range, options = {}) {
 
   // Remove all of the middle nodes, between the splits.
   if (middles.size) {
-    middles.forEach(child => {
+    middles.forEach((child) => {
       transform.removeNodeByKey(child.key, OPTS)
     })
   }
@@ -793,7 +793,7 @@ export function setInlineAtRange(transform, range, properties, options = {}) {
   const inlines = document.getInlinesAtRange(range)
 
   inlines.forEach((inline) => {
-    transform.setNodeByKey(inline.key, properties, { normalize})
+    transform.setNodeByKey(inline.key, properties, { normalize })
   })
 }
 
@@ -940,7 +940,7 @@ export function unwrapBlockAtRange(transform, range, properties, options = {}) {
     })
 
     const firstMatch = children.first()
-    let lastMatch = children.last()
+    const lastMatch = children.last()
 
     if (first == firstMatch && last == lastMatch) {
       block.nodes.forEach((child, i) => {
@@ -1061,23 +1061,25 @@ export function wrapBlockAtRange(transform, range, block, options = {}) {
   const lastblock = blocks.last()
   let parent, siblings, index
 
-  // if there is only one block in the selection then we know the parent and siblings
+  // If there is only one block in the selection then we know the parent and
+  // siblings.
   if (blocks.length === 1) {
     parent = document.getParent(firstblock.key)
     siblings = blocks
   }
 
-  // determine closest shared parent to all blocks in selection
+  // Determine closest shared parent to all blocks in selection.
   else {
-    parent = document.getClosest(firstblock.key, p1 => {
+    parent = document.getClosest(firstblock.key, (p1) => {
       return !!document.getClosest(lastblock.key, p2 => p1 == p2)
     })
   }
 
-  // if no shared parent could be found then the parent is the document
+  // If no shared parent could be found then the parent is the document.
   if (parent == null) parent = document
 
-  // create a list of direct children siblings of parent that fall in the selection
+  // Create a list of direct children siblings of parent that fall in the
+  // selection.
   if (siblings == null) {
     const indexes = parent.nodes.reduce((ind, node, i) => {
       if (node == firstblock || node.hasDescendant(firstblock.key)) ind[0] = i
@@ -1089,15 +1091,15 @@ export function wrapBlockAtRange(transform, range, block, options = {}) {
     siblings = parent.nodes.slice(indexes[0], indexes[1] + 1)
   }
 
-  // get the index to place the new wrapped node at
+  // Get the index to place the new wrapped node at.
   if (index == null) {
     index = parent.nodes.indexOf(siblings.first())
   }
 
-  // inject the new block node into the parent
+  // Inject the new block node into the parent.
   transform.insertNodeByKey(parent.key, index, block, OPTS)
 
-  // move the sibling nodes into the new block node
+  // Move the sibling nodes into the new block node.
   siblings.forEach((node, i) => {
     transform.moveNodeByKey(node.key, block.key, i, OPTS)
   })
@@ -1140,7 +1142,7 @@ export function wrapInlineAtRange(transform, range, inline, options = {}) {
   let startBlock = document.getClosestBlock(startKey)
   let endBlock = document.getClosestBlock(endKey)
   let startChild = startBlock.getHighestChild(startKey)
-  let endChild = endBlock.getHighestChild(endKey)
+  const endChild = endBlock.getHighestChild(endKey)
   const startIndex = startBlock.nodes.indexOf(startChild)
   const endIndex = endBlock.nodes.indexOf(endChild)
 
diff --git a/src/transforms/by-key.js b/src/transforms/by-key.js
index 3eabd429a..cd71c8f16 100644
--- a/src/transforms/by-key.js
+++ b/src/transforms/by-key.js
@@ -170,7 +170,7 @@ export function removeMarkByKey(transform, key, offset, length, mark, options =
 export function removeNodeByKey(transform, key, options = {}) {
   const { normalize = true } = options
   const { state } = transform
-  let { document } = state
+  const { document } = state
   const path = document.getPath(key)
 
   transform.removeNodeOperation(path)
@@ -195,7 +195,7 @@ export function removeNodeByKey(transform, key, options = {}) {
 export function removeTextByKey(transform, key, offset, length, options = {}) {
   const { normalize = true } = options
   const { state } = transform
-  let { document } = state
+  const { document } = state
   const path = document.getPath(key)
 
   transform.removeTextOperation(path, offset, length)
@@ -272,8 +272,8 @@ export function setNodeByKey(transform, key, properties, options = {}) {
 
 export function splitNodeByKey(transform, key, offset, options = {}) {
   const { normalize = true } = options
-  let { state } = transform
-  let { document } = state
+  const { state } = transform
+  const { document } = state
   const path = document.getPath(key)
 
   transform.splitNodeAtOffsetOperation(path, offset)
@@ -353,27 +353,26 @@ export function unwrapNodeByKey(transform, key, options = {}) {
 
 
   if (parent.nodes.size === 1) {
-    // Remove the parent
+    // Remove the parent and replace it by the node itself.
     transform.removeNodeByKey(parent.key, { normalize: false })
-    // and replace it by the node itself
     transform.insertNodeByKey(parentParent.key, parentIndex, node, options)
   }
 
   else if (isFirst) {
-    // Just move the node before its parent
+    // Just move the node before its parent.
     transform.moveNodeByKey(key, parentParent.key, parentIndex, options)
   }
 
   else if (isLast) {
-    // Just move the node after its parent
+    // Just move the node after its parent.
     transform.moveNodeByKey(key, parentParent.key, parentIndex + 1, options)
   }
 
   else {
     const parentPath = document.getPath(parent.key)
-    // Split the parent
+    // Split the parent.
     transform.splitNodeOperation(parentPath, index)
-    // Extract the node in between the splitted parent
+    // Extract the node in between the splitted parent.
     transform.moveNodeByKey(key, parentParent.key, parentIndex + 1, { normalize: false })
 
     if (normalize) {
diff --git a/src/transforms/normalize.js b/src/transforms/normalize.js
index 93ad987e1..dc48f5d9a 100644
--- a/src/transforms/normalize.js
+++ b/src/transforms/normalize.js
@@ -132,7 +132,7 @@ function normalizeNodeAndChildren(transform, node, schema) {
       node = refindNode(transform, node)
 
       // Add any new children back onto the stack.
-      node.nodes.forEach(n => {
+      node.nodes.forEach((n) => {
         if (set.has(n.key)) return
         stack = stack.push(n.key)
       })
@@ -171,7 +171,7 @@ function refindNode(transform, node) {
  */
 
 function normalizeNode(transform, node, schema) {
-  let max = schema.rules.length
+  const max = schema.rules.length
   let iterations = 0
 
   function iterate(t, n) {
diff --git a/src/transforms/on-history.js b/src/transforms/on-history.js
index 5daa478a1..2e882f1c7 100644
--- a/src/transforms/on-history.js
+++ b/src/transforms/on-history.js
@@ -11,7 +11,7 @@ export function redo(transform) {
   let { undos, redos } = history
 
   // If there's no next snapshot, abort.
-  let next = redos.peek()
+  const next = redos.peek()
   if (!next) return
 
   // Shift the next state into the undo stack.
@@ -19,7 +19,7 @@ export function redo(transform) {
   undos = undos.push(next)
 
   // Replay the next operations.
-  next.forEach(op => {
+  next.forEach((op) => {
     transform.applyOperation(op)
   })
 
@@ -82,7 +82,7 @@ export function undo(transform) {
   let { undos, redos } = history
 
   // If there's no previous snapshot, abort.
-  let previous = undos.peek()
+  const previous = undos.peek()
   if (!previous) return
 
   // Shift the previous operations into the redo stack.
@@ -90,8 +90,8 @@ export function undo(transform) {
   redos = redos.push(previous)
 
   // Replay the inverse of the previous operations.
-  previous.slice().reverse().forEach(op => {
-    op.inverse.forEach(inv => {
+  previous.slice().reverse().forEach((op) => {
+    op.inverse.forEach((inv) => {
       transform.applyOperation(inv)
     })
   })
diff --git a/src/transforms/operations.js b/src/transforms/operations.js
index b6121989b..3d2656aac 100644
--- a/src/transforms/operations.js
+++ b/src/transforms/operations.js
@@ -440,7 +440,7 @@ export function splitNodeAtOffsetOperation(transform, path, offset) {
     type: 'join_node',
     path: inversePath,
     withPath: path,
-    // we will split down to the text nodes, so we must join nodes recursively
+    // We will split down to the text nodes, so we must join nodes recursively.
     deep: true
   }]
 
diff --git a/src/utils/get-transfer-data.js b/src/utils/get-transfer-data.js
index 53d55e91c..39c9d2153 100644
--- a/src/utils/get-transfer-data.js
+++ b/src/utils/get-transfer-data.js
@@ -20,9 +20,9 @@ const FRAGMENT_MATCHER = /data-slate-fragment="([^\s]+)"/
 function getTransferData(transfer) {
   let fragment = transfer.getData(TYPES.FRAGMENT) || null
   let node = transfer.getData(TYPES.NODE) || null
-  let html = transfer.getData('text/html') || null
-  let rich = transfer.getData('text/rtf') || null
-  let text = transfer.getData('text/plain') || null
+  const html = transfer.getData('text/html') || null
+  const rich = transfer.getData('text/rtf') || null
+  const text = transfer.getData('text/plain') || null
   let files
 
   // If there isn't a fragment, but there is HTML, check to see if the HTML is
diff --git a/src/utils/offset-key.js b/src/utils/offset-key.js
index 2411ade25..c5ca6e34e 100644
--- a/src/utils/offset-key.js
+++ b/src/utils/offset-key.js
@@ -69,7 +69,6 @@ function findKey(rawNode, rawOffset) {
 
   // Find the closest parent with an offset key attribute.
   let closest = parentNode.closest(SELECTOR)
-  let offsetKey
 
   // For void nodes, the element with the offset key will be a cousin, not an
   // ancestor, so find it by going down from the nearest void parent.
@@ -81,7 +80,7 @@ function findKey(rawNode, rawOffset) {
   }
 
   // Get the string value of the offset key attribute.
-  offsetKey = closest.getAttribute(ATTRIBUTE)
+  const offsetKey = closest.getAttribute(ATTRIBUTE)
 
   // If we still didn't find an offset key, abort.
   if (!offsetKey) return null
diff --git a/src/utils/scroll-to.js b/src/utils/scroll-to.js
index 66ef5c473..f5d488d57 100644
--- a/src/utils/scroll-to.js
+++ b/src/utils/scroll-to.js
@@ -8,7 +8,7 @@ import getWindow from 'get-window'
 function scrollWindow(window, cursorTop, cursorLeft, cursorHeight) {
   let scrollX = window.scrollX
   let scrollY = window.scrollY
-  let cursorBottom = cursorTop + cursorHeight
+  const cursorBottom = cursorTop + cursorHeight
 
   if (cursorTop < 0 || cursorBottom > window.innerHeight) {
     scrollY += cursorTop - window.innerHeight / 2 + cursorHeight / 2
@@ -22,26 +22,26 @@ function scrollWindow(window, cursorTop, cursorLeft, cursorHeight) {
 }
 
 function scrollTo(element) {
-  let window = getWindow(element)
-  let s = window.getSelection()
+  const window = getWindow(element)
+  const s = window.getSelection()
   if (s.rangeCount > 0) {
-    let selectionRect = s.getRangeAt(0).getBoundingClientRect()
+    const selectionRect = s.getRangeAt(0).getBoundingClientRect()
     let innerRect = selectionRect
     let wrapper = element
-    let cursorHeight = innerRect.height
+    const cursorHeight = innerRect.height
     let cursorTop = innerRect.top
     let cursorLeft = innerRect.left
 
     while (wrapper != window.document.body) {
-      let wrapperRect = wrapper.getBoundingClientRect()
-      let currentY = cursorTop
-      let cursorBottom = cursorTop + cursorHeight
+      const wrapperRect = wrapper.getBoundingClientRect()
+      const currentY = cursorTop
+      const cursorBottom = cursorTop + cursorHeight
       if (cursorTop < wrapperRect.top || cursorBottom > wrapperRect.top + wrapper.offsetHeight) {
         cursorTop = wrapperRect.top + wrapperRect.height / 2 - cursorHeight / 2
         wrapper.scrollTop += currentY - cursorTop
       }
 
-      let currentLeft = cursorLeft
+      const currentLeft = cursorLeft
       if (cursorLeft < wrapperRect.left || cursorLeft > wrapperRect.right) {
         cursorLeft = wrapperRect.left + wrapperRect.width / 2
         wrapper.scrollLeft += currentLeft - cursorLeft