diff --git a/README.md b/README.md
index 7f84481..4d1c5eb 100644
--- a/README.md
+++ b/README.md
@@ -27,13 +27,16 @@ For development and tests:
 python -m pip install -e ".[test,lint]"
 ```
 
-For a Conda-based development environment with DFTB+ included:
+For a Conda-based development environment with all calculation backends
+(DFTB+, `modes`, xtb, tblite) included:
 
 ```bash
 conda env create -f environment.yml
 conda activate thermoscreening
 ```
 
+Then `thermo doctor` should report every backend as found.
+
 ## DFTB+ Setup
 
 DFTB+ calculations require two external pieces:
diff --git a/environment.yml b/environment.yml
index a434486..49b2e60 100644
--- a/environment.yml
+++ b/environment.yml
@@ -3,7 +3,10 @@ channels:
   - conda-forge
 dependencies:
   - python>=3.12
-  - dftbplus
+  # calculation backends (compiled programs; pip cannot install these)
+  - dftbplus        # DFTB+ engine: provides `dftb+` and `modes`
+  - xtb             # native xtb binary, for `--engine xtb-cli`
+  - tblite-python   # GFN-xTB via tblite, for `--engine xtb`
   - pip
   - pip:
       - "-e .[test,lint]"