diff --git a/package.json b/package.json
index 145b75a..a119b9a 100644
--- a/package.json
+++ b/package.json
@@ -31,6 +31,7 @@
     "randomcolor": "^0.4.4",
     "react": "^15.4.0",
     "react-addons-pure-render-mixin": "^15.4.0",
+    "react-codemirror": "^0.3.0",
     "react-collapse": "^2.3.3",
     "react-color": "^2.10.0",
     "react-dom": "^15.4.0",
diff --git a/src/codemirror-maputnik.css b/src/codemirror-maputnik.css
new file mode 100644
index 0000000..c5808a1
--- /dev/null
+++ b/src/codemirror-maputnik.css
@@ -0,0 +1,43 @@
+.cm-s-maputnik.CodeMirror {
+  height: 100%;
+  font-size: 10px;
+}
+
+.cm-s-maputnik.CodeMirror, .cm-s-maputnik .CodeMirror-gutters {
+  background: transparent;
+  color: #8e8e8e;
+  border: none;
+}
+.cm-s-maputnik .CodeMirror-cursor {
+    border-left: solid thin #8e8e8e !important;
+}
+
+.cm-s-maputnik.CodeMirror-focused div.CodeMirror-selected {
+  background: rgba(255, 255, 255, 0.10);
+}
+
+.cm-s-maputnik .CodeMirror-line::selection,
+.cm-s-maputnik .CodeMirror-line > span::selection,
+.cm-s-maputnik .CodeMirror-line > span > span::selection {
+  background: rgba(255, 255, 255, 0.10);
+}
+
+.cm-s-maputnik .CodeMirror-line::-moz-selection,
+.cm-s-maputnik .CodeMirror-line > span::-moz-selection,
+.cm-s-maputnik .CodeMirror-line > span > span::-moz-selection {
+  background: rgba(255, 255, 255, 0.10);
+}
+
+.cm-s-maputnik span.cm-string, .cm-s-maputnik span.cm-string-2 {
+  color: #8f9d6a;
+}
+.cm-s-maputnik span.cm-number { color: #91675f; }
+.cm-s-maputnik span.cm-property { color: #b8a077; }
+
+.cm-s-maputnik .CodeMirror-activeline-background {
+  background: rgba(255,255,255,0.1);
+}
+
+.cm-s-maputnik .CodeMirror-matchingbracket {
+  text-decoration: underline; color: white !important;
+}
diff --git a/src/components/layers/JSONEditor.jsx b/src/components/layers/JSONEditor.jsx
new file mode 100644
index 0000000..cc93b01
--- /dev/null
+++ b/src/components/layers/JSONEditor.jsx
@@ -0,0 +1,64 @@
+import React from 'react'
+
+import CodeMirror from 'react-codemirror'
+import InputBlock from '../inputs/InputBlock'
+import StringInput from '../inputs/StringInput'
+import SelectInput from '../inputs/SelectInput'
+
+import colors from '../../config/colors'
+import { margins } from '../../config/scales'
+
+import 'codemirror/mode/javascript/javascript'
+import 'codemirror/lib/codemirror.css'
+import '../../codemirror-maputnik.css'
+
+
+class JSONEditor extends React.Component {
+  static propTypes = {
+    layer: React.PropTypes.object.isRequired,
+    onChange: React.PropTypes.func,
+  }
+
+  constructor(props) {
+    super(props)
+    this.state = {
+      code: JSON.stringify(props.layer, null, 2)
+    }
+  }
+
+  componentWillReceiveProps(nextProps) {
+    this.setState({
+      code: JSON.stringify(nextProps.layer, null, 2)
+    })
+  }
+
+  onCodeUpdate(newCode) {
+    try {
+      const parsedLayer = JSON.parse(newCode)
+      this.props.onChange(parsedLayer)
+    } catch(err) {
+      console.warn(err)
+      this.setState({
+        code: newCode
+      })
+    }
+  }
+
+  render() {
+    const codeMirrorOptions = {
+      mode: {name: "javascript", json: true},
+      tabSize: 2,
+      theme: 'maputnik',
+      viewportMargin: Infinity,
+      lineNumbers: false,
+    }
+
+    return <CodeMirror
+      value={this.state.code}
+      onChange={this.onCodeUpdate.bind(this)}
+      options={codeMirrorOptions}
+    />
+  }
+}
+
+export default JSONEditor
diff --git a/src/components/layers/LayerEditor.jsx b/src/components/layers/LayerEditor.jsx
index 8af64cc..873e27e 100644
--- a/src/components/layers/LayerEditor.jsx
+++ b/src/components/layers/LayerEditor.jsx
@@ -1,5 +1,6 @@
 import React from 'react'
 
+import JSONEditor from './JSONEditor'
 import SourceEditor from './SourceEditor'
 import FilterEditor from '../filter/FilterEditor'
 import PropertyGroup from '../fields/PropertyGroup'
@@ -126,6 +127,10 @@ export default class LayerEditor extends React.Component {
         groupFields={fields}
         onChange={this.onPropertyChange.bind(this)}
       />
+      case 'jsoneditor': return <JSONEditor
+        layer={this.props.layer}
+        onChange={this.props.onLayerChanged}
+      />
       default: return null
     }
   }
diff --git a/src/config/layout.json b/src/config/layout.json
index 4e5f561..b947355 100644
--- a/src/config/layout.json
+++ b/src/config/layout.json
@@ -34,6 +34,10 @@
             "line-dasharray",
             "line-gap-width"
           ]
+        },
+        {
+          "title": "JSON",
+          "type": "jsoneditor"
         }
       ]
     },
@@ -55,6 +59,10 @@
             "background-pattern",
             "background-opacity"
           ]
+        },
+        {
+          "title": "JSON",
+          "type": "jsoneditor"
         }
       ]
     },
@@ -80,6 +88,10 @@
             "fill-translate",
             "fill-translate-anchor"
           ]
+        },
+        {
+          "title": "JSON",
+          "type": "jsoneditor"
         }
       ]
     },
@@ -150,6 +162,10 @@
             "icon-keep-upright",
             "icon-offset"
           ]
+        },
+        {
+          "title": "JSON",
+          "type": "jsoneditor"
         }
       ]
     }