Install & Compatibility
Where this runs
tested against v11.1.11 · pip install
no network on importno background threads
Install × environment matrix
Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux
muslpy 3.10–3.95 runs
build_error
glibcpy 3.10–3.95 runs
installs and imports cleanly · install 48.9s · import 6.822s · 1433.6MB
1618MB installed
● package 1618MB
Code
Verified usage
Verified import paths — ran on the pinned version, not inferred.
ErtAnalysisError
✓ from ert.analysis import ErtAnalysisError
Commonly imported from old paths or submodules.
ert
✓ import ert
✗ import libres or import res
The old 'res' or 'libres' package was merged into ERT. Use the top-level 'ert' package.
ErtScript
✓ from ert.script import ErtScript
ErtScript base class for workflows.
ert_config
✓ from ert.config import ErtConfig
Configuration parser.
Load an ERT configuration and demonstrate basic imports.
from ert import ErtConfig
from ert.analysis import ErtAnalysisError
# Load configuration from a file
config = ErtConfig.from_file("config.ert")
print(config)
# Minimal example to run an ensemble experiment
# (requires a valid ERT configuration file with forward model)
# For more details see https://ert.readthedocs.io/en/latest/
ert --version
Errors
Common errors & fixes
ImportError: cannot import name 'ErtAnalysisError' from 'ert'
The symbol is not exposed at the top-level package; it's in a submodule.
fixUse 'from ert.analysis import ErtAnalysisError' instead.
ModuleNotFoundError: No module named 'res'
The old 'res' package was removed in ERT 21.0.0.
fixReplace 'import res' with 'import ert' and update all dependent imports.
TypeError: __init__() got an unexpected keyword argument 'ens_path'
The API changed between versions; 'ens_path' is no longer accepted in the constructor.
fixCheck the ERT API documentation for the correct arguments or use the new configuration-loading approach.
ert configdump: error: unrecognized arguments: --help
The CLI interface changed; use 'ert --help' for top-level help.
fixRun 'ert --help' or 'ert configdump --help' for subcommand help.
Upgrade
Version history
22.0.3latest on PyPI · released Jun 4, 2026
Audit
Dependencies
No dependency data recorded yet.