[Nexus 5 Android Development] dechronic:
EDIT 05 September 2014: Added fstab.hammerhead formatted for f2fs-all and f2fs-data for those who wish to manually replace the ramdisk's fstab.hammerhead in a kernel to mount the partitions as f2fs.

NOTE: This will only work on kernels that have f2fs tools commited to their kernel image. Make sure the kernel you wish to modify has F2FS support otherwise it WILL NOT WORK!

22 July 2014: Made changes to the Android Kitchen to retain the USB stick mount.

16 July 2014 If you have used any previous version of F2FS ROM CONVERTER prior to the date, please update to the latest version in the links below to correct major errors, to put more fault checks in place and provide better instructions for non Nexus 5 devices to use. Version number is in the Window Title from v0.3.

First off I have to say that I did not create any of these tools but rather I brought them together and I modified them to make it straight forward and easier to format the partitions as F2FS, make a ROM F2FS-ALL and modify a kernel for F2FS-ALL or just F2FS-DATA.

I would suggest you click on each link and click Thanks for each of them.

Thanks and links to the original authors and software.

Hammerhead FSTAB files formatted for F2FS-ALL and F2FS-DATA

Note1: Rename the desired file to fstab.hammerhead to replace the exisiting one in the ramdisk.

Note2: Use Android Image Kitchen to unpack and repack a kernel file (boot.img) during which you can replace the fstab.hammerhead

Note3: Some kernels' updater-script mounts /system or /data as EXT4. Therefore it needs to be modified from the original and added back to the zip.

e.g. Change mount("ext4", "EMMC", "/dev/block/platform/msm_sdcc.1/by-name/system", "/system"); to run_program("/sbin/busybox", "mount", "/system");

and change mount("ext4", "EMMC", "/dev/block/platform/msm_sdcc.1/by-name/userdata", "/data"); to run_program("/sbin/busybox", "mount", "/data");

Link: http://d-h.st/l87

Download: follow above link

Thanks: kdh2834

Tool: F2FS and F2FS-ALL kernels modified by kdh2834 with help on how to do it. (Actually it was because of him I can now get my N5 running with a full F2FS-ALL ROM and kernel)

Link: http://xdaforums.com/showpost.php?p=52550395&postcount=1

Thanks: osm0sis

Tool: Android Image Kitchen (for unpacking and repacking a kernel)

Link: http://xdaforums.com/showpost.php?p=36067074&postcount=1

Download my version: http://d-h.st/E74

Thanks: TeamWin

Tool: TWRP recovery for formatting the partitions as F2FS (use the latest version)

Note: It can also show the format of a partition in Wipe -> Advanced Wipe

Link: http://techerrata.com/browse/twrp2/hammerhead

Download follow above link

Thanks: Phil3759 and to rootSU for the Nexus builds

Tool: Philz touch recovery for formatting the partitions as F2FS (use the latest version)

Link: http://xdaforums.com/showpost.php?p=48377548&postcount=1

Download: follow above link

Thanks: legolas93's FormatPartitions.zip

Note: These flashable zips need one of the above recoveries to work

Tool: Flashable zips to format the partitions automatically

Link: http://xdaforums.com/showthread.php?t=2678140

Download my version to format all partitions to F2FS: http://d-h.st/RCz

Download my version to format the data partition to F2FS: http://d-h.st/2AI

Thanks: NABENDU1 for F2FS ROM CONVERTER

Note: Mine has been heavily modified for Nexus 5 phones but can be used by any device

Link: http://xdaforums.com/showpost.php?p=52201672&postcount=1

Tool: F2FS ROM Converter v0.5 to make a flashable ROM with F2FS support.

Download my version: http://d-h.st/Uiq

EDIT: Latest version (v0.5) replaced the AOSP F2FS-ALL kernel (boot-f2fs-all.img) as it was not fully F2FS-ALL compatible. Previous version still had /cache partition as EXT4

EDIT: Latest version (v0.4) has support for Slimkat and similar ROMs that need to mount the /data partition.