I'm switching my deep carry, dress up carry gun from a Kahr PM9 to a Glock 43 this need a new ankle holster, already have appendix and IWB ordered.  

Does anyone make an ankle holster which uses kydex?  I do not want one with a snap closure on the back of the slide. Thanks for any ankle holster suggestions.

Here's what I've been using for a few years now.  Very comfortable and easy on my ankle.  The only drawback is re-holstering.  I figured if I'm in a place where I have to draw from my ankle holster, it's probably a bad situation and re-holstering will be the least of my troubles.  I'm thinking I could just put the pistol in a pocket until I can properly re-holster the weapon.  It's called the 'Cozy Partner' by Renegade Holsters, Phoenix, AZ.

It was recommended to me by a friend of mine who works for the Feds.  But alas, the company that made the holster has gone out of business.  Another company has picked up were Renegade Holster Co. left off.  Check out the link for the new 'Cozy Partner' holster.
http://www.prweb.com/releases/2015/07/prweb12820338.htm

Alessi or his understudy skip Ritchie not cheap but mine is still going strong after 30 years

I think Fobus makes what you are looking for.

I personally prefer the strap on an ankle holster. Especially if you have to move quickly. Galco Ankle Glove is my absolute favorite. Can wear that thing all day. Completely forget I have it on.

I actually already ordered the Fobus, reviews say great retention, can run without it coming out

Love the Galco ankle glove

I've used several and the best I've found is 5-Shot Leather

+1

Good decision, I use one everyday and am very happy.  Just don't wear pants on the shorter side.  Some of my jeans expose the tip of the holster when crossing my legs at work.

I just ordered a Gould and Goodrich ankle holster that seems to be damn near the same thing as the galco ankle glove. Should arrive tomorrow.

Bought a crossbreed from crossbreed seconds. Good price, works well with claf strap.

I really want to try a Gould & Goodrich bootlock for duty.