diff --git a/modules/01-working-in-jupyterhub/bring_own.png b/modules/01-working-in-jupyterhub/bring_own.png
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index 0000000..e6dd1c9
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diff --git a/modules/01-working-in-jupyterhub/build_your_own.png b/modules/01-working-in-jupyterhub/build_your_own.png
new file mode 100644
index 0000000..e7c2aef
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diff --git a/modules/01-working-in-jupyterhub/image_tags.png b/modules/01-working-in-jupyterhub/image_tags.png
new file mode 100644
index 0000000..1d0eca2
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diff --git a/modules/01-working-in-jupyterhub/index.md b/modules/01-working-in-jupyterhub/index.md
index 3bd3ad8..b096874 100644
--- a/modules/01-working-in-jupyterhub/index.md
+++ b/modules/01-working-in-jupyterhub/index.md
@@ -17,7 +17,7 @@ authors:
 :class: dropdown
 
 <iframe
-    src="https://docs.google.com/presentation/d/e/2PACX-1vRe2ACdsZHjAfG_dpS_ZkDjLLG3qizsQCgWBgAXzetJlPz7DKVXWx3nrSfEK-LGEs_H8myf21tQzR9o/pubembed?start=false&loop=false&delayms=60000"
+    src="https://docs.google.com/presentation/d/e/2PACX-1vQHM2_0pwRCghPvFFHDvH-KMzD5seeR2D9NkPrFWPyPBSJBsN50uIc81x6rDthVIyroOXqH5rRKPZL7/pubembed?start=false&loop=false&delayms=60000"
     frameborder="0"
     width="960"
     height="569"
@@ -34,18 +34,13 @@ authors:
 :::
 
 
-## Access the [CryoCloud powerpoint](https://docs.google.com/presentation/d/1sj5oSAnHQ5Le0zMNqy55T-esZqro-WjVOPJdv_BR08M/edit?usp=sharing) whenever you need to reference it
+## Access the [CryoCloud powerpoint](https://docs.google.com/presentation/d/1BRWaZUEfBJlKA9WL7jIdL_4jlQ24wohS_GNjYJCFliw/edit?usp=sharing) whenever you need to reference it
 
-Open the powerpoint by directly clicking on the hyperlink above or to open it in the CryoCloud Linux Desktop web browser as follows:
-
-- Copy this hyperlink: `https://docs.google.com/presentation/d/1sj5oSAnHQ5Le0zMNqy55T-esZqro-WjVOPJdv_BR08M/edit?usp=sharing`
-- Click on the plus (`+`) sign in the `File Browser` to the left to open a `Launcher` window
-- Under Notebooks, click on `Desktop` to access the Linux Desktop. This will open a new tab.
-- Click on the `Web Browser` tool (globe) at the bottom of the screen
-- Paste the url into the search bar
+Open the powerpoint by directly clicking on the hyperlink above.
 
 ![](./slides.png)
 
+---
 
 ## Open CryoCloud
 
@@ -63,18 +58,157 @@ server and having to rerun your analysis.**
 :::
 
 3) Sit back and learn about each of the tools!
+    - How to bring your own environment
     - JupyterHub options and viewing setup
-    - Github
+    - GitHub
     - Virtual Linux desktop
     - SyncThing
     - Viewing and editing of different files
 
-Now after the demo...
+---
+
+## Bring Your Own environment (custom Docker image)
+
+CryoCloud allows you to launch your server using different software environments. Each environment corresponds to a Docker image, which defines the libraries, tools, and versions available to you. Switching Docker images is similar to switching between computers that have different applications installed.
+
+Using a custom Docker image is useful when you want:
+- A different software stack than the defaults
+- An older or reproducible version of CryoCloud’s environment
+- A specialized environment from an external registry (e.g., Pangeo, Rocker)
+
+This feature is called **Bring Your Own Image (BYOI)**.
+
+
+### 1. Selecting an environment when launching CryoCloud
+
+When you open CryoCloud, the **Environment** dropdown provides:
+
+- Python
+- R
+- Matlab
+- Other
+- Build Your Own
+
+To use a custom Docker image, select **Other**.
+A field labeled **Custom image** will appear. This is where you will paste the Docker tag for the environment you want.
+
+![](./bring_own.png)
+
+
+### 2. Finding a Docker tag
+
+A Docker tag tells CryoCloud which exact environment to use. You can choose tags from CryoCloud’s maintained images or from Docker Hub.
+
+
+### Option A: Use an older or alternate CryoCloud environment
+
+CryoCloud publishes its Python environment image to Quay.io, Red Hat’s hosted container image registry service which is free for publicly accessible container images.
+
+1. Visit the repository tags page:
+   https://quay.io/repository/cryointhecloud/cryo-hub-image?tab=tags
+
+2. Browse the available tags. Each tag corresponds to a specific version.
+
+3. Copy the full tag in the following form: `quay.io/cryointhecloud/cryo-hub-image:<tag>`
+
+Example:
+
+```
+quay.io/cryointhecloud/cryo-hub-image:e457bd429a1e
+```
+
+Paste the tag into the **Custom image** field on CryoCloud. For reference, this image is built from the code in: https://github.com/CryoInTheCloud/hub-image.
+
+```{image} ./image_tags.png
+:width: 60%
+:align: center
+```
+
+### Option B: Use an image from Docker Hub
+
+You may also use any public Docker image from Docker Hub.
+
+1. Search for images at:
+   https://hub.docker.com/
+
+2. Tags typically follow this format: `account/image:tag`
+
+Example:
+```
+pangeo/ml-notebook:latest
+rocker/geospatial:4.4
+```
+
+Paste any valid tag into the **Custom image** field.
+
 
+### Example: Using a machine learning environment
+
+If you want a Pangeo machine learning environment, enter:
+```
+pangeo/ml-notebook:latest
+```
+
+CryoCloud will launch your session using that environment.
+
+
+### Tips
+
+- If an image does not launch, ensure it includes a Jupyter-compatible single-user interface.
+- Private images requiring authentication are not currently supported through the UI.
+- Images must be Linux-based and appropriate for JupyterHub.
+- Use explicit tags (not `latest`) when reproducibility is important.
+
+---
+
+## Build Your Own image
+
+CryoCloud also supports creating a fully customized environment using your own `environment.yml` file. This option is useful when you want complete control over the software stack and only want the packages you specify.
+
+When launching CryoCloud, select **Build Your Own** from the **Environment** dropdown.
+A field labeled **Repository** will appear. This is where you will paste the URL of a GitHub repository that contains an `environment.yml` file.
+
+![](./build_your_own.png)
+
+
+### Example: Using a minimal template repository
+
+You can start with a simple example environment from the following template repository:
+
+```
+https://github.com/tsnow03/BuildOwnImage_template_env.git
+```
+
+To copy the correct link from your own repository:
+
+1. Open your GitHub repository.
+2. Click the blue **Code** button.
+3. Copy the HTTPS URL (it should end in `.git`).
+
+CryoCloud will use the `environment.yml` found in that repository to build your image.
+
+
+### Building the Image
+
+1. Paste the repository URL into the **Repository** field.
+2. Click **Build image**.
+
+CryoCloud will begin building a Docker image based on your `environment.yml`. Build times vary depending on the number of packages:
+
+- Simple environments: ~30 seconds
+- Large or complex environments: up to ~1 hour
+
+If the build process encounters an issue, an error message will appear in the log so you can revise your `environment.yml`.
+
+After the image is built once, you can easily select it again in future sessions.
+
+**Tip:** Test your `environment.yml` locally using Mamba before using Build Your Own to speed up the build process and avoid waiting through repeated failures.
+
+---
 
 ## Task: Clone the CryoCloud jupyterbook
 
-We will import the [CryoCloud Website Github repository](https://github.com/CryoInTheCloud/CryoCloudWebsite.git).
+We will clone (e.g. make a local copy of) the [workshop repository](https://github.com/geojupyter/workshop-open-source-geospatial.git).
 
 To do this:
 1. Select the plus (`+`) sign above the `File Browser` to the left, which will bring up a `Launcher` window.
@@ -91,20 +225,25 @@ To do this:
    cd yourfoldername
    ```
 
-3. Now clone the hackweek code into your current directory:
+3. Now clone the workshop code into your current directory:
 
    ```
-   https://github.com/CryoInTheCloud/CryoCloudWebsite.git
+   https://github.com/geojupyter/workshop-open-source-geospatial.git
    ```
 
 4. You will see the folder pop into your `File Browser` on the left if you have the current directory open.
    Click on the folder to navigate through the files.
 
-5. To open this tutorial, click on the `book` subdirectory > `tutorials` and double
-   click on `CryoCloud`.
+5. To open this tutorial, click on the `materials` subdirectory > `01-working-in-jupyterhub` and double
+   click on `index.md`.
    This should open up this tutorial in case you want to review it in the future.
 
 
+Now after the demo...
+
+
+---
+
 ## Shutting down your JupyterHub
 
 ```{tip}
@@ -121,12 +260,16 @@ We prefer you shut down the server when so we save that 90 minutes of computing
 To do so:
 
 - In upper left, click on `File` > `Hub Control Panel`, which will open another tab
-- Click the `Stop Server` button. Once this button disappears after you clicked it, your server is off.
+- Click the red `Stop Server` button. Once this button disappears after you clicked it, your server is off.
 - Click `Log Out` in the top right of your screen and you will be logged out, or you can start a new server
 - You can now close this tab and the other tab where you were just working
 
-![](./stop_server.png)
+```{image} ./stop_server.png
+:width: 70%
+:align: center
+```
 
+---
 
 ## Summary
 
diff --git a/modules/01-working-in-jupyterhub/slides.png b/modules/01-working-in-jupyterhub/slides.png
index cb8e83e..58050f4 100644
Binary files a/modules/01-working-in-jupyterhub/slides.png and b/modules/01-working-in-jupyterhub/slides.png differ
diff --git a/pixi.lock b/pixi.lock
index be9624a..fa8ec48 100644
--- a/pixi.lock
+++ b/pixi.lock
@@ -12,6 +12,7 @@ environments:
       - conda: https://conda.anaconda.org/conda-forge/noarch/ca-certificates-2025.11.12-hbd8a1cb_0.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/icu-75.1-he02047a_0.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/ld_impl_linux-64-2.45-default_hbd61a6d_104.conda
+      - conda: https://conda.anaconda.org/conda-forge/linux-64/libabseil-20250512.1-cxx17_hba17884_0.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/libbrotlicommon-1.2.0-hb03c661_1.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/libbrotlidec-1.2.0-hb03c661_1.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/libbrotlienc-1.2.0-hb03c661_1.conda
@@ -32,19 +33,20 @@ environments:
       - conda: https://conda.anaconda.org/conda-forge/linux-64/libzlib-1.3.1-hb9d3cd8_2.conda
       - conda: https://conda.anaconda.org/conda-forge/noarch/mystmd-1.7.0-pyhcf101f3_0.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/ncurses-6.5-h2d0b736_3.conda
-      - conda: https://conda.anaconda.org/conda-forge/linux-64/nodejs-24.10.0-h36edbcc_2.conda
+      - conda: https://conda.anaconda.org/conda-forge/linux-64/nodejs-25.2.1-he2c55a7_1.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/openssl-3.6.0-h26f9b46_0.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/python-3.14.2-h32b2ec7_100_cp314.conda
       - conda: https://conda.anaconda.org/conda-forge/noarch/python_abi-3.14-8_cp314.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/readline-8.2-h8c095d6_2.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/tk-8.6.13-noxft_ha0e22de_103.conda
-      - conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h78e105d_0.conda
+      - conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h8577fbf_1.conda
       - conda: https://conda.anaconda.org/conda-forge/linux-64/zstd-1.5.7-hb78ec9c_6.conda
       osx-arm64:
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/bzip2-1.0.8-hd037594_8.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/c-ares-1.34.6-hc919400_0.conda
       - conda: https://conda.anaconda.org/conda-forge/noarch/ca-certificates-2025.11.12-hbd8a1cb_0.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/icu-75.1-hfee45f7_0.conda
+      - conda: https://conda.anaconda.org/conda-forge/osx-arm64/libabseil-20250512.1-cxx17_hd41c47c_0.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/libbrotlicommon-1.2.0-hc919400_1.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/libbrotlidec-1.2.0-hc919400_1.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/libbrotlienc-1.2.0-hc919400_1.conda
@@ -60,13 +62,13 @@ environments:
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/libzlib-1.3.1-h8359307_2.conda
       - conda: https://conda.anaconda.org/conda-forge/noarch/mystmd-1.7.0-pyhcf101f3_0.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/ncurses-6.5-h5e97a16_3.conda
-      - conda: https://conda.anaconda.org/conda-forge/osx-arm64/nodejs-24.10.0-h64c5147_2.conda
+      - conda: https://conda.anaconda.org/conda-forge/osx-arm64/nodejs-25.2.1-h5230ea7_1.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/openssl-3.6.0-h5503f6c_0.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/python-3.14.2-h40d2674_100_cp314.conda
       - conda: https://conda.anaconda.org/conda-forge/noarch/python_abi-3.14-8_cp314.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/readline-8.2-h1d1bf99_2.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/tk-8.6.13-h892fb3f_3.conda
-      - conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h78e105d_0.conda
+      - conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h8577fbf_1.conda
       - conda: https://conda.anaconda.org/conda-forge/osx-arm64/zstd-1.5.7-hbf9d68e_6.conda
 packages:
 - conda: https://conda.anaconda.org/conda-forge/linux-64/_libgcc_mutex-0.1-conda_forge.tar.bz2
@@ -166,6 +168,33 @@ packages:
   license_family: GPL
   size: 725545
   timestamp: 1764007826689
+- conda: https://conda.anaconda.org/conda-forge/linux-64/libabseil-20250512.1-cxx17_hba17884_0.conda
+  sha256: dcd1429a1782864c452057a6c5bc1860f2b637dc20a2b7e6eacd57395bbceff8
+  md5: 83b160d4da3e1e847bf044997621ed63
+  depends:
+  - __glibc >=2.17,<3.0.a0
+  - libgcc >=13
+  - libstdcxx >=13
+  constrains:
+  - libabseil-static =20250512.1=cxx17*
+  - abseil-cpp =20250512.1
+  license: Apache-2.0
+  license_family: Apache
+  size: 1310612
+  timestamp: 1750194198254
+- conda: https://conda.anaconda.org/conda-forge/osx-arm64/libabseil-20250512.1-cxx17_hd41c47c_0.conda
+  sha256: 7f0ee9ae7fa2cf7ac92b0acf8047c8bac965389e48be61bf1d463e057af2ea6a
+  md5: 360dbb413ee2c170a0a684a33c4fc6b8
+  depends:
+  - __osx >=11.0
+  - libcxx >=18
+  constrains:
+  - libabseil-static =20250512.1=cxx17*
+  - abseil-cpp =20250512.1
+  license: Apache-2.0
+  license_family: Apache
+  size: 1174081
+  timestamp: 1750194620012
 - conda: https://conda.anaconda.org/conda-forge/linux-64/libbrotlicommon-1.2.0-hb03c661_1.conda
   sha256: 318f36bd49ca8ad85e6478bd8506c88d82454cc008c1ac1c6bf00a3c42fa610e
   md5: 72c8fd1af66bd67bf580645b426513ed
@@ -304,6 +333,7 @@ packages:
   - libgcc-ng ==15.2.0=*_16
   - libgomp 15.2.0 he0feb66_16
   license: GPL-3.0-only WITH GCC-exception-3.1
+  license_family: GPL
   size: 1042798
   timestamp: 1765256792743
 - conda: https://conda.anaconda.org/conda-forge/linux-64/libgcc-ng-15.2.0-h69a702a_16.conda
@@ -312,6 +342,7 @@ packages:
   depends:
   - libgcc 15.2.0 he0feb66_16
   license: GPL-3.0-only WITH GCC-exception-3.1
+  license_family: GPL
   size: 27256
   timestamp: 1765256804124
 - conda: https://conda.anaconda.org/conda-forge/linux-64/libgomp-15.2.0-he0feb66_16.conda
@@ -320,6 +351,7 @@ packages:
   depends:
   - __glibc >=2.17,<3.0.a0
   license: GPL-3.0-only WITH GCC-exception-3.1
+  license_family: GPL
   size: 603284
   timestamp: 1765256703881
 - conda: https://conda.anaconda.org/conda-forge/linux-64/liblzma-5.8.1-hb9d3cd8_2.conda
@@ -421,6 +453,7 @@ packages:
   constrains:
   - libstdcxx-ng ==15.2.0=*_16
   license: GPL-3.0-only WITH GCC-exception-3.1
+  license_family: GPL
   size: 5856456
   timestamp: 1765256838573
 - conda: https://conda.anaconda.org/conda-forge/linux-64/libstdcxx-ng-15.2.0-hdf11a46_16.conda
@@ -429,6 +462,7 @@ packages:
   depends:
   - libstdcxx 15.2.0 h934c35e_16
   license: GPL-3.0-only WITH GCC-exception-3.1
+  license_family: GPL
   size: 27300
   timestamp: 1765256885128
 - conda: https://conda.anaconda.org/conda-forge/linux-64/libuuid-2.41.2-h5347b49_1.conda
@@ -511,48 +545,52 @@ packages:
   license: X11 AND BSD-3-Clause
   size: 797030
   timestamp: 1738196177597
-- conda: https://conda.anaconda.org/conda-forge/linux-64/nodejs-24.10.0-h36edbcc_2.conda
-  sha256: 3c1d59afd09c52dac76eed71b1e3b8d4b8502db151745216c036ad57808b82bb
-  md5: e2484efbb090278c0070dee87d9cdb21
+- conda: https://conda.anaconda.org/conda-forge/linux-64/nodejs-25.2.1-he2c55a7_1.conda
+  sha256: 6516f99fe400181ebe27cba29180ca0c7425c15d7392f74220a028ad0e0064a2
+  md5: d8005b3a90515c952b51026f6b7d005d
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   - libstdcxx >=14
   - libgcc >=14
-  - libzlib >=1.3.1,<2.0a0
-  - icu >=75.1,<76.0a0
-  - c-ares >=1.34.5,<2.0a0
+  - zstd >=1.5.7,<1.6.0a0
+  - c-ares >=1.34.6,<2.0a0
   - libuv >=1.51.0,<2.0a0
+  - libsqlite >=3.51.1,<4.0a0
+  - libnghttp2 >=1.67.0,<2.0a0
   - openssl >=3.5.4,<4.0a0
+  - libabseil >=20250512.1,<20250513.0a0
+  - libabseil * cxx17*
+  - libzlib >=1.3.1,<2.0a0
   - libbrotlicommon >=1.2.0,<1.3.0a0
   - libbrotlienc >=1.2.0,<1.3.0a0
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-  - zstd >=1.5.7,<1.6.0a0
-  - libnghttp2 >=1.67.0,<2.0a0
+  - icu >=75.1,<76.0a0
   license: MIT
-  size: 23504771
-  timestamp: 1765210770135
-- conda: https://conda.anaconda.org/conda-forge/osx-arm64/nodejs-24.10.0-h64c5147_2.conda
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-  md5: f3573bab908a11e6ed14265832779de6
+  license_family: MIT
+  size: 17246248
+  timestamp: 1765444698486
+- conda: https://conda.anaconda.org/conda-forge/osx-arm64/nodejs-25.2.1-h5230ea7_1.conda
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+  md5: 0b6dfe96bcfb469afe82885b3fecbd56
   depends:
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-  - libzlib >=1.3.1,<2.0a0
+  - zstd >=1.5.7,<1.6.0a0
+  - libabseil >=20250512.1,<20250513.0a0
+  - libabseil * cxx17*
   - libnghttp2 >=1.67.0,<2.0a0
   - libuv >=1.51.0,<2.0a0
+  - libzlib >=1.3.1,<2.0a0
   license: MIT
-  license_family: MIT
-  size: 16182130
-  timestamp: 1765047982974
+  size: 16202237
+  timestamp: 1765482731453
 - conda: https://conda.anaconda.org/conda-forge/linux-64/openssl-3.6.0-h26f9b46_0.conda
   sha256: a47271202f4518a484956968335b2521409c8173e123ab381e775c358c67fe6d
   md5: 9ee58d5c534af06558933af3c845a780
@@ -677,12 +715,12 @@ packages:
   license_family: BSD
   size: 3125484
   timestamp: 1763055028377
-- conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h78e105d_0.conda
-  sha256: 5aaa366385d716557e365f0a4e9c3fca43ba196872abbbe3d56bb610d131e192
-  md5: 4222072737ccff51314b5ece9c7d6f5a
+- conda: https://conda.anaconda.org/conda-forge/noarch/tzdata-2025b-h8577fbf_1.conda
+  sha256: 865716d3e2ccaca1218462645830d2370ab075a9a118c238728e1231a234bc6c
+  md5: e4e8496b68cf5f25e76fbe67f3856550
   license: LicenseRef-Public-Domain
-  size: 122968
-  timestamp: 1742727099393
+  size: 119010
+  timestamp: 1765580300078
 - conda: https://conda.anaconda.org/conda-forge/linux-64/zstd-1.5.7-hb78ec9c_6.conda
   sha256: 68f0206ca6e98fea941e5717cec780ed2873ffabc0e1ed34428c061e2c6268c7
   md5: 4a13eeac0b5c8e5b8ab496e6c4ddd829