diff --git a/README.md b/README.md
index cb00316..38e8ae2 100644
--- a/README.md
+++ b/README.md
@@ -29,13 +29,28 @@ Raise an exception if a firmware build is earlier than a given date.
 Time a function's execution using a decorator
 
 ## fastbuild - Pyboard use under Linux
-Build MicroPython with your frozen bytecode, put the Pyboard into DFU mode, and deploy the build to
-the board with a single command. Takes just over 60 seconds on a fast PC. Note the use of make's j
-argument to use mutliple cores. Empirically 8 gave the fastest build on my core i7 4/8 core laptop:
-adjust to suit your PC.
+Build MicroPython with your frozen bytecode, put the Pyboard into DFU mode, and
+deploy the build to the board with a single command. Takes just over 60 seconds
+on a fast PC. Note the use of make's j argument to use mutliple cores.
+Empirically 8 gave the fastest build on my core i7 4/8 core laptop: adjust to
+suit your PC.
 
-Includes udev rules to avoid jumps from /dev/ttyACM0 to /dev/ttyACM1: ensures Pyboards of all types
-appear as /dev/pyboard. Also rules for USB connected WiPy and FTDI USB/serial adaptor.
+Includes udev rules to avoid jumps from /dev/ttyACM0 to /dev/ttyACM1: ensures
+Pyboards of all types appear as /dev/pyboard. Also rules for USB connected WiPy
+and FTDI USB/serial adaptor.
+
+Improved build script: ``buildpyb``  
+This checks the attached pyboard. If it's a V1.0, V1.1 or Lite it builds the
+correct firmware and deploys it. Otherwise it produces an error message. It uses
+the supplied ``pyb_check`` utility which depends on ``pyboard.py`` being on the
+path. Install (from micropython/tools) and test first.
+
+Optional argument ``--clean`` - if supplied does a ``make clean``. Strongly
+recommended after pulling new sourcecode.
+
+There are a couple of site specifics here. ``pyb_check`` assumes the udev rule
+above is applied to put the device on ``/dev/pyboard``. ``buildpyb`` assumes a
+frozen modules directory ``stmhal/modules``. Modify to suit.
 
 ## ESP8266
 benchmark.py Tests the performance of MQTT by periodically publishing while subscribed to
diff --git a/fastbuild/buildpyb b/fastbuild/buildpyb
new file mode 100755
index 0000000..cd0c564
--- /dev/null
+++ b/fastbuild/buildpyb
@@ -0,0 +1,41 @@
+#! /bin/bash
+# Detect pyboard variant build and deploy
+# requires pyb_check
+# Also requires the pyboard utility to be on the path
+
+BOARD=""
+if pyb_check PYBV11
+then
+    BOARD="PYBV11"
+fi
+if pyb_check PYBV10
+then
+    BOARD="PYBV10"
+fi
+if pyb_check PYBLITEV10
+then
+    BOARD="PYBLITEV10"
+fi
+echo $BOARD
+
+if [ $BOARD ]
+then
+    cd /mnt/qnap2/data/Projects/MicroPython/micropython/stmhal
+    if [ $# -eq 1 ] && [ $1 = "--clean" ]
+    then
+        make BOARD=$BOARD clean
+    fi
+    if make -j 8 BOARD=$BOARD FROZEN_MPY_DIR=modules && pyb_boot
+    then
+        sleep 1
+        sudo make BOARD=$BOARD deploy
+        cd -
+        sleep 1
+        rshell
+    else
+        echo Build failure
+    fi
+else
+    echo Incorrect board type
+fi
+
diff --git a/fastbuild/pyb_check b/fastbuild/pyb_check
new file mode 100755
index 0000000..223a4aa
--- /dev/null
+++ b/fastbuild/pyb_check
@@ -0,0 +1,31 @@
+#! /usr/bin/python3
+# -*- coding: utf-8 -*-
+
+# Called from buildpyb
+# Arg: expected board type
+# exit status 0 if hardware matches board type else 1
+
+import sys
+import os, os.path
+import pyboard
+device = '/dev/pyboard'
+errmsg = 'Must supply board type PYBV10 PYBV11 PYBLITEV10'
+d = {'PYBV11' : b'PYBv1.1', 'PYBV10' : b'PYBv1.0', 'PYBLITEV10' : b'PYBLITEv1.0'}
+def main():
+    if len(sys.argv) < 2:
+        print(errmsg)
+        sys.exit(1)
+    if not os.path.exists(device):
+        sys.exit(1)
+    pybd = pyboard.Pyboard('/dev/pyboard')
+    pybd.enter_raw_repl()
+    hardware = pybd.exec('import os; print(os.uname()[4].split(' ')[0])').strip()
+    pybd.exit_raw_repl()
+    board = d[sys.argv[1]]
+    if board == hardware:
+        sys.exit(0)
+    sys.exit(1)
+
+if __name__ == "__main__":
+    main()
+