diff --git a/.circleci/config.yml b/.circleci/config.yml
index 62751f4c..ba0d02ed 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -45,7 +45,7 @@ commands:
 jobs:
   prep_env:
     docker:
-      - image: tlaurion/heads-dev-env:v0.1.1
+      - image: tlaurion/heads-dev-env:v0.1.3
     resource_class: large
     working_directory: ~/heads
     steps:
@@ -111,7 +111,7 @@ jobs:
 
   build_and_persist:
     docker:
-      - image: tlaurion/heads-dev-env:v0.1.1
+      - image: tlaurion/heads-dev-env:v0.1.3
     resource_class: large
     working_directory: ~/heads
     parameters:
@@ -139,7 +139,7 @@ jobs:
 
   build:
     docker:
-      - image: tlaurion/heads-dev-env:v0.1.1
+      - image: tlaurion/heads-dev-env:v0.1.3
     resource_class: large
     working_directory: ~/heads
     parameters:
@@ -160,7 +160,7 @@ jobs:
 
   save_cache:
     docker:
-      - image: tlaurion/heads-dev-env:v0.1.1
+      - image: tlaurion/heads-dev-env:v0.1.3
     resource_class: large
     working_directory: ~/heads
     steps:
diff --git a/README.md b/README.md
index a0819f48..d1505693 100644
--- a/README.md
+++ b/README.md
@@ -28,8 +28,49 @@ Please refer to [Heads-wiki](https://osresearch.net) for your Heads' documentati
 
 Building heads
 ===
+
+Build docker from nix develop layer locally
+====
+
+```
+sh <(curl -L https://nixos.org/nix/install) --no-daemon
+  . /home/user/.nix-profile/etc/profile.d/nix.sh
+nix build .#dockerImage && docker load < result
+```
+
+Jump into docker image
+=====
+`docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) linuxboot/heads:dev-env`
+
+Build a board from docker image
+=====
 `make BOARD=board_name` where board_name is the name of the board directory under `./boards` directory.
 
+
+Use prepared docker image from docker hub
+====
+```
+docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) tlaurion/heads-dev-env:latest -- make BOARD=qemu-coreboot-whiptail-tpm2
+docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) tlaurion/heads-dev-env:latest -- make BOARD=qemu-coreboot-whiptail-tpm2 run
+```
+
+Maintenance notes on docker image
+===
+Redo the steps above in case the flake.nix or nix.lock changes. Then publish on docker hub:
+
+```
+docker tag tlaurion/heads-dev-env:vx.y.z tlaurion/heads-dev-env:latest
+docker push tlaurion/heads-dev-env:latest
+```
+
+Notes:
+- Local builds can use ":latest" 
+- To reproduce CirlceCI results, make sure to use the same versioned tag declared under .circleci/config.yml's "image:" 
+
+
+
+General notes on reproducible builds
+===
 In order to build reproducible firmware images, Heads builds a specific
 version of gcc and uses it to compile the Linux kernel and various tools
 that go into the initrd.  Unfortunately this means the first step is a
diff --git a/targets/qemu.md b/targets/qemu.md
index 0dfdd63e..1587fa88 100644
--- a/targets/qemu.md
+++ b/targets/qemu.md
@@ -1,4 +1,4 @@
-qemu-coreboot-(fb)whiptail-tpm[1,2](-hotp) boards
+qemu-coreboot-(fb)whiptail-tpmX(-hotp) boards
 ===
 
 The `qemu-coreboot-fbwhiptail-tpm1-hotp` configuration (and their variants) permits testing of most features of Heads.  
@@ -87,3 +87,14 @@ swtpm on Debian bookworm
 ===
 1. Install dependencies
    * `sudo apt install swtpm swtpm-tools`
+
+swtpm on nix docker image
+===
+Nothing to do. Everything needed is in the docker image.
+
+Just make sure to pass DISPLAY environement variable on your docker command line. eg:
+* Remotely downloaded docker image (doing make command only inside of docker example):
+  * `docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) tlaurion/heads-dev-env:latest -- make BOARD=qemu-coreboot-whiptail-tpm2`
+  * `docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) tlaurion/heads-dev-env:latest -- make BOARD=qemu-coreboot-whiptail-tpm2 run`
+* Locally created docker image from nix develop environment (jumping into docker image variation of the above, where developer does what he wants within):
+  * `docker run -e DISPLAY=$DISPLAY --network host --rm -ti -v $(pwd):$(pwd) -w $(pwd) linuxboot/heads:dev-env`