diff --git a/HISTORY.rst b/HISTORY.rst
index 64cd9797..989e9c39 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -4,6 +4,13 @@ Release History
 PlatformIO 2.0
 --------------
 
+2.6.3 (2015-12-21)
+~~~~~~~~~~~~~~~~~~
+
+* Restored support for Espressif ESP8266 ESP-01 1MB board (ready for OTA)
+* Fixed invalid ROM size for ESP8266-based boards
+  (`issue #396 <https://github.com/platformio/platformio/issues/396>`_)
+
 2.6.2 (2015-12-21)
 ~~~~~~~~~~~~~~~~~~
 
diff --git a/docs/_static/extra.css b/docs/_static/extra.css
index 846e05d9..1513daa2 100644
--- a/docs/_static/extra.css
+++ b/docs/_static/extra.css
@@ -29,7 +29,8 @@ nav {
   margin-right: auto;
   margin-left: auto;
 }
-@media (min-width: 768px) {
+
+@media (min-width: 992px) {
   #pionav {
     display: block !important;
   }
@@ -39,11 +40,7 @@ nav {
   .wy-nav-side {
     top: 50px;
   }
-  .container {
-    width: 750px;
-  }
-}
-@media (min-width: 992px) {
+
   .container {
     width: 970px;
   }
@@ -94,6 +91,7 @@ nav {
   position: relative;
   display: block;
   padding: 10px 15px;
+  font-size: 14px;
 }
 .nav > li > a:hover,
 .nav > li > a:focus {
@@ -103,6 +101,9 @@ nav {
 .nav > li > a > img {
   max-width: none;
 }
+.nav > li > a > i {
+  margin-right: 5px;
+}
 
 .navbar {
   position: relative;
diff --git a/docs/_templates/footer.html b/docs/_templates/footer.html
index 5b562649..65446636 100644
--- a/docs/_templates/footer.html
+++ b/docs/_templates/footer.html
@@ -11,16 +11,16 @@
     <nav role="navigation">
       <div>
         <ul class="nav navbar-nav">
-          <li><a href="http://platformio.org/#!/get-started"><i class="fa fa-rocket fa-lg"></i> Get Started</a></li>
-          <li><a href="http://platformio.org/#!/platforms"><i class="fa fa-laptop fa-lg"></i> Platforms</a></li>
-          <li><a href="http://platformio.org/#!/frameworks"><i class="fa fa-cogs fa-lg"></i> Frameworks</a></li>
-          <li><a href="http://platformio.org/#!/boards"><i class="fa fa-gamepad fa-lg"></i> Boards</a></li>
-          <li ><a href="http://platformio.org/#!/lib"><i class="fa fa-code fa-lg"></i> Libraries</a></li>
+          <li><a href="http://platformio.org/#!/get-started"><i class="fa fa-rocket fa-lg"></i>Get Started</a></li>
+          <li><a href="http://platformio.org/#!/platforms"><i class="fa fa-laptop fa-lg"></i>Platforms</a></li>
+          <li><a href="http://platformio.org/#!/frameworks"><i class="fa fa-cogs fa-lg"></i>Frameworks</a></li>
+          <li><a href="http://platformio.org/#!/boards"><i class="fa fa-gamepad fa-lg"></i>Boards</a></li>
+          <li ><a href="http://platformio.org/#!/lib"><i class="fa fa-code fa-lg"></i>Libraries</a></li>
         </ul>
 
         <ul class="nav navbar-nav navbar-right">
-          <li><a href="http://platformio.org/#!/who-uses"><i class="fa fa-heart-o fa-lg"></i> Who uses</a></li>
-          <li class="active"><a href="http://docs.platformio.org/"><i class="fa fa-book fa-lg"></i> Docs</a></li>
+          <li><a href="http://platformio.org/#!/who-uses"><i class="fa fa-heart-o fa-lg"></i>Who uses</a></li>
+          <li class="active"><a href="http://docs.platformio.org/"><i class="fa fa-book fa-lg"></i>Docs</a></li>
         </ul>
       </div>
 
@@ -39,7 +39,7 @@
         }
         window.setTimeout(fixScroll, 50);
         $(window).on('hashchange', function(e){fixScroll();});
-    });  
+    });
   };
 
   var timer = function() {
diff --git a/docs/frameworks/arduino.rst b/docs/frameworks/arduino.rst
index 7bfac12f..07395193 100644
--- a/docs/frameworks/arduino.rst
+++ b/docs/frameworks/arduino.rst
@@ -81,7 +81,7 @@ Adafruit
       - `Adafruit HUZZAH ESP8266 <https://www.adafruit.com/products/2471>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
     * - ``protrinket3``
@@ -461,7 +461,7 @@ ESPino
       - `ESPino <http://www.espino.io>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Engduino
@@ -512,19 +512,26 @@ Espressif
       - RAM
 
     * - ``esp01``
-      - `Espressif Generic ESP8266 ESP-01 <https://nurdspace.nl/ESP8266>`_
+      - `Espressif Generic ESP8266 ESP-01 512k <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
       - ESP8266
       - 80 MHz
       - 512 Kb
       - 80 Kb
 
-    * - ``esp12e``
-      - `Espressif ESP8266 ESP-12E <https://nurdspace.nl/ESP8266>`_
+    * - ``esp01_1m``
+      - `Espressif Generic ESP8266 ESP-01 1M <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
       - ESP8266
       - 80 MHz
       - 1024 Kb
       - 80 Kb
 
+    * - ``esp12e``
+      - `Espressif ESP8266 ESP-12E <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
+      - ESP8266
+      - 80 MHz
+      - 4096 Kb
+      - 80 Kb
+
 LightUp
 ~~~~~~~
 
@@ -665,7 +672,7 @@ NodeMCU
       - `NodeMCU 0.9 & 1.0 <http://www.nodemcu.com/>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Olimex
@@ -685,7 +692,7 @@ Olimex
       - `Olimex MOD-WIFI-ESP8266(-DEV) <https://www.olimex.com/Products/IoT/MOD-WIFI-ESP8266-DEV/open-source-hardware>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 2048 Kb
       - 80 Kb
 
 PanStamp
@@ -984,7 +991,7 @@ SweetPea
       - `SweetPea ESP-210 <http://wiki.sweetpeas.se/index.php?title=ESP-210>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Teensy
@@ -1079,14 +1086,14 @@ WeMos
       - `WeMos D1 <http://www.wemos.cc/wiki/doku.php?id=en:d1>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
     * - ``d1_mini``
       - `WeMos D1 mini <http://www.wemos.cc/wiki/doku.php?id=en:d1_mini>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Wicked Device
diff --git a/docs/platforms/espressif.rst b/docs/platforms/espressif.rst
index deaa30c6..c745b855 100644
--- a/docs/platforms/espressif.rst
+++ b/docs/platforms/espressif.rst
@@ -89,7 +89,7 @@ Adafruit
       - `Adafruit HUZZAH ESP8266 <https://www.adafruit.com/products/2471>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 ESPino
@@ -109,7 +109,7 @@ ESPino
       - `ESPino <http://www.espino.io>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Espressif
@@ -126,19 +126,26 @@ Espressif
       - RAM
 
     * - ``esp01``
-      - `Espressif Generic ESP8266 ESP-01 <https://nurdspace.nl/ESP8266>`_
+      - `Espressif Generic ESP8266 ESP-01 512k <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
       - ESP8266
       - 80 MHz
       - 512 Kb
       - 80 Kb
 
-    * - ``esp12e``
-      - `Espressif ESP8266 ESP-12E <https://nurdspace.nl/ESP8266>`_
+    * - ``esp01_1m``
+      - `Espressif Generic ESP8266 ESP-01 1M <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
       - ESP8266
       - 80 MHz
       - 1024 Kb
       - 80 Kb
 
+    * - ``esp12e``
+      - `Espressif ESP8266 ESP-12E <http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family>`_
+      - ESP8266
+      - 80 MHz
+      - 4096 Kb
+      - 80 Kb
+
 NodeMCU
 ~~~~~~~
 
@@ -156,7 +163,7 @@ NodeMCU
       - `NodeMCU 0.9 & 1.0 <http://www.nodemcu.com/>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 Olimex
@@ -176,7 +183,7 @@ Olimex
       - `Olimex MOD-WIFI-ESP8266(-DEV) <https://www.olimex.com/Products/IoT/MOD-WIFI-ESP8266-DEV/open-source-hardware>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 2048 Kb
       - 80 Kb
 
 SparkFun
@@ -216,7 +223,7 @@ SweetPea
       - `SweetPea ESP-210 <http://wiki.sweetpeas.se/index.php?title=ESP-210>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 WeMos
@@ -236,14 +243,14 @@ WeMos
       - `WeMos D1 <http://www.wemos.cc/wiki/doku.php?id=en:d1>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
     * - ``d1_mini``
       - `WeMos D1 mini <http://www.wemos.cc/wiki/doku.php?id=en:d1_mini>`_
       - ESP8266
       - 80 MHz
-      - 1024 Kb
+      - 4096 Kb
       - 80 Kb
 
 .. include:: espressif_extra.rst
diff --git a/docs/platforms/espressif_extra.rst b/docs/platforms/espressif_extra.rst
index d089886f..3747f654 100644
--- a/docs/platforms/espressif_extra.rst
+++ b/docs/platforms/espressif_extra.rst
@@ -12,6 +12,8 @@
 OTA update
 ----------
 
+Firstly, please read `What is OTA? How to use it? <https://github.com/esp8266/Arduino/blob/master/doc/ota_updates/ota_updates.md>`_
+
 There are 2 options:
 
 * Directly specify :option:`platformio run --upload-port` in command line
diff --git a/examples/espressif/esp8266-webserver/platformio.ini b/examples/espressif/esp8266-webserver/platformio.ini
index e25bd946..f25248bb 100644
--- a/examples/espressif/esp8266-webserver/platformio.ini
+++ b/examples/espressif/esp8266-webserver/platformio.ini
@@ -22,6 +22,11 @@ platform = espressif
 framework = arduino
 board = esp01
 
+[env:esp01_1m]
+platform = espressif
+framework = arduino
+board = esp01_1m
+
 [env:nodemcu]
 platform = espressif
 framework = arduino
diff --git a/platformio/__init__.py b/platformio/__init__.py
index 235dd071..adf23bc5 100644
--- a/platformio/__init__.py
+++ b/platformio/__init__.py
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-VERSION = (2, 6, 2)
+VERSION = (2, 6, 3)
 __version__ = ".".join([str(s) for s in VERSION])
 
 __title__ = "platformio"
diff --git a/platformio/boards/espressif.json b/platformio/boards/espressif.json
index 53cffe70..80825526 100644
--- a/platformio/boards/espressif.json
+++ b/platformio/boards/espressif.json
@@ -9,7 +9,7 @@
             "variant": "generic"
         },
         "frameworks": ["arduino"],
-        "name": "Espressif Generic ESP8266 ESP-01",
+        "name": "Espressif Generic ESP8266 ESP-01 512k",
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
@@ -18,7 +18,30 @@
             "require_upload_port" : true,
             "speed": 115200
         },
-        "url": "https://nurdspace.nl/ESP8266",
+        "url": "http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family",
+        "vendor": "Espressif"
+    },
+
+    "esp01_1m": {
+        "build": {
+            "core": "esp8266",
+            "extra_flags": "-DESP8266 -DARDUINO_ARCH_ESP8266 -DARDUINO_ESP8266_ESP01",
+            "f_cpu": "80000000L",
+            "ldscript": "esp8266.flash.1m256.ld",
+            "mcu": "esp8266",
+            "variant": "generic"
+        },
+        "frameworks": ["arduino"],
+        "name": "Espressif Generic ESP8266 ESP-01 1M",
+        "platform": "espressif",
+        "upload": {
+            "maximum_ram_size": 81920,
+            "maximum_size": 1048576,
+            "resetmethod": "ck",
+            "require_upload_port" : true,
+            "speed": 115200
+        },
+        "url": "http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family",
         "vendor": "Espressif"
     },
 
@@ -36,12 +59,12 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "nodemcu",
             "require_upload_port" : true,
             "speed": 115200
         },
-        "url": "https://nurdspace.nl/ESP8266",
+        "url": "http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family",
         "vendor": "Espressif"
     },
 
@@ -59,7 +82,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "nodemcu",
             "require_upload_port" : true,
             "speed": 115200
@@ -82,7 +105,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "nodemcu",
             "require_upload_port" : true,
             "speed": 115200
@@ -105,7 +128,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 2097152,
             "resetmethod": "ck",
             "require_upload_port" : true,
             "speed": 115200
@@ -151,7 +174,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "ck",
             "require_upload_port" : true,
             "speed": 115200
@@ -174,7 +197,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "nodemcu",
             "require_upload_port" : true,
             "speed": 460800
@@ -197,7 +220,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "nodemcu",
             "require_upload_port" : true,
             "speed": 460800
@@ -220,7 +243,7 @@
         "platform": "espressif",
         "upload": {
             "maximum_ram_size": 81920,
-            "maximum_size": 1048576,
+            "maximum_size": 4194304,
             "resetmethod": "ck",
             "require_upload_port" : true,
             "speed": 115200
diff --git a/platformio/builder/scripts/espressif.py b/platformio/builder/scripts/espressif.py
index 6ffa0fb0..4e3c62b3 100644
--- a/platformio/builder/scripts/espressif.py
+++ b/platformio/builder/scripts/espressif.py
@@ -16,6 +16,7 @@
     Builder for Espressif MCUs
 """
 
+import re
 import socket
 from os.path import join
 
@@ -27,9 +28,32 @@ def BeforeUpload(target, source, env):  # pylint: disable=W0613,W0621
     env.AutodetectUploadPort()
 
 
+def _get_flash_size(env):  # pylint: disable=redefined-outer-name
+    # use board's flash size by default
+    board_max_size = int(
+        env.get("BOARD_OPTIONS", {}).get("upload", {}).get("maximum_size", 0))
+
+    # check if user overrides
+    for f in env.get("LINKFLAGS", []):
+        if "-Wl,-T" not in f:
+            continue
+        match = re.search(r"-Wl,-T.*\.flash\.(\d+)(m|k).*\.ld", env.subst(f))
+        if not match:
+            continue
+        if match.group(2) == "k":
+            board_max_size = int(match.group(1)) * 1024
+        elif match.group(2) == "m":
+            board_max_size = int(match.group(1)) * 1024 * 1024
+
+    return ("%dK" % (board_max_size / 1024) if board_max_size < 1048576
+            else "%dM" % (board_max_size / 1048576))
+
+
 env = DefaultEnvironment()
 
 env.Replace(
+    __get_flash_size=_get_flash_size,
+
     AR="xtensa-lx106-elf-ar",
     AS="xtensa-lx106-elf-as",
     CC="xtensa-lx106-elf-gcc",
@@ -98,8 +122,6 @@ env.Replace(
     PROGSUFFIX=".elf"
 )
 
-_board_max_rom = int(
-    env.get("BOARD_OPTIONS", {}).get("upload", {}).get("maximum_size", 0))
 env.Append(
     BUILDERS=dict(
         ElfToBin=Builder(
@@ -111,9 +133,7 @@ env.Append(
                 "-bo", "$TARGET",
                 "-bm", "dio",
                 "-bf", "${BOARD_OPTIONS['build']['f_cpu'][:2]}",
-                "-bz",
-                "%dK" % (_board_max_rom / 1024) if _board_max_rom < 1048576
-                else "%dM" % (_board_max_rom / 1048576),
+                "-bz", "${__get_flash_size(__env__)}",
                 "-bs", ".text",
                 "-bp", "4096",
                 "-ec",