diff --git a/fastbuild/README.md b/fastbuild/README.md
index da2e0a1..d69aa69 100644
--- a/fastbuild/README.md
+++ b/fastbuild/README.md
@@ -18,25 +18,52 @@ and `pyb_check` to determine the type of attached board. These use the
 `pyboard.py` module in the source tree to execute scripts on the attached
 board.
 
-21st Oct 2019  
-Script modified to ignore the new FROZEN_MANIFEST system. It continues to work
-without needing any change to the file layout. When some docs for the manifest
-appear I will amend the script and this doc.
+The scripts will require minor edits to reflect your directory structure.
 
 ###### [Main README](../README.md)
 
-### Optional Edits
+# Frozen modules and manifests
 
-In the `buildpyb` script you may wish to edit the `-j 8` argument to `make`.
-This radically speeds build on a multi core PC. Empirically 8 gave the fastest
-build on my Core i7 4/8 core laptop: adjust to suit your PC.
+The method of specifying modules to be frozen has changed (as of Oct 2019).
+The files and directories to be frozen are now specified in a file with the
+default name `manifest.py`. This may be found in `/ports/stm32/boards` or the
+eqivalent for other ports.
 
-This script defaults to a frozen modules directory `stmhal/modules`. This may
-be overridden by creating an environment variable FROZEN_DIR: a recent update
-enabled the directory for frozen to be located anywhere in the filesystem,
-allowing project specific directories.
+In practice it can be advantageous to override the default. You might want to
+freeze a different set of files depending on the specific board or project.
+This is done by issuing
+```
+make BOARD=$BOARD FROZEN_MANIFEST=$MANIFEST
+```
+where `BOARD` specifies the target (e.g. 'PYBV11') and `MANIFEST` specifies the
+path to the manifest file (e.g. '~/my_manifest.py').
 
-In `buildnew` you may wish to delete the unix make commands.
+A simple manifest file comprises `freeze` calls with one or two args. The first
+is a directory specifier. If the second exists it can specify a single file or
+more, by passing an iterable. Consider the following manifest file:
+```python
+freeze('$(MPY_DIR)/drivers/dht', 'dht.py')
+freeze('$(MPY_DIR)/tools', ('upip.py', 'upip_utarfile.py'))
+freeze('/path/to/pyb_d_modules')
+```
+Taking the lines in order:
+ 1. The single file argument freezes the file 'dht.py' found in the MicroPython
+ source tree `drivers` directory.
+ 2. Passing an iterable causes the two specified files to be frozen.
+ 3. Passing a directory without arguments causes all files and subdirectories
+ to be frozen. Assume '../pyb_d_modules' contains a file `rats.py` and a
+ subdirectory `foo` containing `bar.py`. Then `help('modules')` will show
+ `rats` and `foo/bar`. This means that Python packages are frozen correctly.
+
+On Linux symlinks are handled as you would expect.
+
+# The build scripts
+
+### Optional Edit (all scripts)
+
+In these scripts you may wish to edit the `-j 8` argument to `make`. This
+radically speeds build on a multi core PC. Empirically 8 gave the fastest build
+on my Core i7 4/8 core laptop: adjust to suit your PC.
 
 ### Dependencies and setup (on PC)
 
@@ -53,6 +80,18 @@ cp 49-micropython.rules /etc/udev/rules.d
 pip3 install rshell
 ```
 
+The build scripts expect an environment variable MPDIR holding the path to the
+MicroPython source tree. To set this up, as normal user issue (edited for your
+path to the MicroPython source tree):
+
+```
+cd ~
+echo export MPDIR='/mnt/qnap2/data/Projects/MicroPython/micropython' >> .bashrc
+echo >> .bashrc
+```
+
+Close and restart the terminal session before proceding.
+
 Verify that `pyboard.py` works. To do this, close and restart the terminal
 session. Run Python3, paste the following and check that the red LED lights:
 
@@ -67,24 +106,19 @@ pyb.exec('pyb.LED(1).on()')
 pyb.exit_raw_repl()
 ```
 
-The build scripts expect an environment variable MPDIR holding the path to the
-MicroPython source tree. To set this up, as normal user issue (edited for your
-path to the MicroPython source tree):
-
-```
-cd ~
-echo export MPDIR='/mnt/qnap2/data/Projects/MicroPython/micropython' >> .bashrc
-echo >> .bashrc
-```
-
-Close and restart the terminal session before running the scripts.
-
 ### Build script: `buildpyb`  
 
 This checks the attached pyboard. If it's a V1.0, V1.1 or Lite it or a Pyboard
 D series it builds the correct firmware and deploys it. Otherwise it produces
 an error message.
 
+It freezes a different set of files depending on whether the board is a Pyboard
+V1.x or a Pyboard D. It can readily be adapted for finer-grain control or to
+produce project-specific builds.
+
+You will need to change the `MANIFESTS` variable which is the directory
+specifier for my manifest files.
+
 Optional argument `--clean` - if supplied does a `make clean` to delete
 all files produced by the previous build before proceeding.
 
@@ -93,7 +127,14 @@ all files produced by the previous build before proceeding.
 Report state of master branch, update sources and issue `make clean` for
 Pyboard variants and ESP8266. Builds cross compiler and unix port.
 
+If you don't use the Unix build you may wish to delete the unix make commands.
+
 ### ESP8266 Build
 
 `buildesp` A script to build and deploy ESP8266 firmware. Accepts optional
-`--clean` argument.
+`--clean` or `--erase` arguments. Both perform a `make clean` but the second
+also erases the ESP8266 flash.
+
+You will need to change the `MANIFEST` variable which is the directory
+specifier for my esp8266 manifest file.
+
diff --git a/fastbuild/buildesp b/fastbuild/buildesp
index 66ea0b6..48c7721 100755
--- a/fastbuild/buildesp
+++ b/fastbuild/buildesp
@@ -1,5 +1,6 @@
 #! /bin/bash
 cd /mnt/qnap2/data/Projects/MicroPython/micropython/ports/esp8266
+MANIFEST='/mnt/qnap2/Scripts/manifests/esp8266_manifest.py'
 
 if [ $# -eq 1 ] && [ $1 = "--clean" ]
 then
@@ -12,10 +13,10 @@ then
     esptool.py  --port /dev/ttyUSB0 erase_flash
 fi
 
-if make -j 8
+if make -j 8 FROZEN_MANIFEST=$MANIFEST
 then
     sleep 1
-    esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --verify --flash_size=detect -fm dio 0 build-GENERIC/firmware-combined.bin
+    esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash --flash_size=detect -fm dio 0 build-GENERIC/firmware-combined.bin
     cd -
     sleep 4
     rshell -p /dev/ttyUSB0 --editor nano --buffer-size=30
diff --git a/fastbuild/buildpyb b/fastbuild/buildpyb
index 3a5c1f5..da57e0b 100755
--- a/fastbuild/buildpyb
+++ b/fastbuild/buildpyb
@@ -5,9 +5,18 @@
 # Also requires the pyboard.py utility to be on the path (micropython/tools/pyboard.py)
 
 MPDEVICE='/dev/pyboard'
-
+MANIFESTS='/mnt/qnap2/Scripts/manifests'
 # Determine board type
 BOARD=$(pyb_check $MPDEVICE)
+# Currently have only two manifest variants for V1.x and D
+if [[ $BOARD == 'PYBV11' || $BOARD == 'PYBV10' || $BOARD == 'PYBLITEV10' ]]
+then
+    MANIFEST=$MANIFESTS/pyb_v1_manifest.py
+fi
+if [[ $BOARD == 'PYBD_SF2' || $BOARD == 'PYBD_SF3' || $BOARD == 'PYBD_SF6' ]]
+then
+    MANIFEST=$MANIFESTS/pyb_d_manifest.py
+fi
 
 # Check for user override of frozen directory
 if [ $FROZEN_DIR ]
@@ -25,10 +34,10 @@ then
     then
         make BOARD=$BOARD clean
     fi
-    if make -j 8 BOARD=$BOARD FROZEN_MPY_DIR=$FROZEN_DIR FROZEN_MANIFEST= && pyb_boot $MPDEVICE
+    if make -j 8 BOARD=$BOARD FROZEN_MANIFEST=$MANIFEST && pyb_boot $MPDEVICE
     then
         sleep 1
-        make PYTHON=python3 BOARD=$BOARD FROZEN_MPY_DIR=$FROZEN_DIR FROZEN_MANIFEST= deploy
+        make PYTHON=python3 BOARD=$BOARD FROZEN_MANIFEST=$MANIFEST deploy
     else
         echo Build failure
     fi