Update readme

README.md

@@ -1,10 +1,8 @@
 # eobs_environment
 [![Build environment](https://github.com/ECA-D/eobs_environment/actions/workflows/build_environment.yml/badge.svg)](https://github.com/ECA-D/eobs_environment/actions/workflows/build_environment.yml)
 
-
 Software environment for running E-OBS code
 
-*This repository is in a testing phase*
 
 ## How to use
 This repository is the testbed for testing the installation procedure for `eobs` code.
@@ -13,6 +11,10 @@ The goal of the repository is to assure one can easily install the required depe
 
 When working with the latest version of `eobs` and `E-OBS_batch` (both from this organization), one should be able to install everything (on a linux host).
 
+There are two use-cases:
+ - A local installation (see below).
+ - Installation to a so-called `tykky` environment on ECMWF.
+
 ### 1. Install `miniforge`
 
 Run the following commands, and follow the install guide of miniforge:
@@ -40,7 +42,33 @@ Which first installs the `conda`-packages in `conda_env.txt`. Some packages are
 #### 4. Install `eobs` from source
 This step is currently not available
 
-### 5. Test for a succesfull installation
+### 5. Test for a successful installation
 ```bash
 bash run_minimal_test.sh
 ```
+
+## `tykky` environment
+On ECMWF, we use a so-called `tykky` environment as recommended by the [user documentation](https://confluence.ecmwf.int/display/UDOC/HPC2020%3A+Python+support).
+Therefore, on the ECMWF HPC, one may instead follow these steps to create a `tykky`:
+```bash
+# Start an interactive session with more memory for building the environment
+ecinteractive -m 20GB -c 1
+# Load python for running the tykky wrapper script, called create_tykky_env.py
+module load python3
+export TYKKY_PATH=$HPCPERM/tykky
+# Build the image, the name after "-n" will be the new environment name.
+# See python3 create_tykky_env.py --help for more options.
+# This step usually takes about 30 minutes
+time python3 create_tykky_env.py -n <NAME>
+
+# To activate the environment, run:
+module load tykky
+tykky activate <NAME>
+
+# NB! At the time of writing (2025-08-11), there is an issue with tykky on ECMWF, which causes race conditions with sed.
+# Therefore  change the execution level:
+chmod -x $(which sed)
+
+# Check that the software was succesfully installed:
+bash run_miniml_test.sh
+```

create_tykky_env.py

@@ -1,10 +1,11 @@
 """
-Only works on ATOS, to run:
+Only works on ATOS/ECMWF, to run:
 module load python3
 export TYKKY_PATH=$HPCPERM/tykky
-time python3 create_tykky_env.py -n eobs_v25.07
+time python3 create_tykky_env.py -n eobs_v25.08
 
-Installing with tykky on atos is a bit tricky, since conda-containerize changes paths during the installation, so we need to have absolute paths.
+Installing with tykky on atos is a bit tricky, since conda-containerize changes
+paths during the installation, so we need to have absolute paths.
 For that reason, we convert the conda-requirements to a yaml file.
 """
 
@@ -20,6 +21,7 @@
 module load tykky
 conda-containerize new --mamba --prefix {tykky_path}/{env_name} {yaml_file}
 conda-containerize update {tykky_path}/{env_name} --post-install {abs_path}/install_step1_R.sh
+conda-containerize update {tykky_path}/{env_name} --post-install {abs_path}/install_step2_pip.sh
 """
 yaml_template = """
 channels: