diff --git a/conda-recipe/meta.yaml b/conda-recipe/meta.yaml
index f88f3e7a0a..e364904f7e 100644
--- a/conda-recipe/meta.yaml
+++ b/conda-recipe/meta.yaml
@@ -44,7 +44,7 @@ requirements:
         - joblib
         - sphinx_rtd_theme >0.5
         - sphinxcontrib-bibtex
-        - ruamel.yaml <0.18
+        - ruamel.yaml >=0.15
 
 test:
     requires:
diff --git a/extra_tests/regression_checks.py b/extra_tests/regression_checks.py
index 855c398fd5..e5976d54dc 100644
--- a/extra_tests/regression_checks.py
+++ b/extra_tests/regression_checks.py
@@ -9,7 +9,7 @@
 import pytest
 
 from n3fit.tests.test_fit import EXE, check_fit_results
-from reportengine.compat import yaml
+from validphys.utils import yaml_safe
 
 REGRESSION_FOLDER = pathlib.Path(__file__).with_name("regression_fits")
 
@@ -37,7 +37,7 @@ def test_regression_fit(tmp_path, runcard, replica, regenerate):
     runcard_file = REGRESSION_FOLDER / runcard_name
     shutil.copy(runcard_file, tmp_path)
 
-    runcard_info = yaml.load(runcard_file.read_text())
+    runcard_info = yaml_safe.load(runcard_file.read_text())
     if (wname := runcard_info.get("load")) is not None:
         shutil.copy(REGRESSION_FOLDER / wname, tmp_path)
 
diff --git a/n3fit/src/evolven3fit/evolve.py b/n3fit/src/evolven3fit/evolve.py
index eb6e27960d..fb10a4db84 100644
--- a/n3fit/src/evolven3fit/evolve.py
+++ b/n3fit/src/evolven3fit/evolve.py
@@ -11,7 +11,7 @@
 
 import eko
 from eko import basis_rotation, runner
-from reportengine.compat import yaml
+from validphys.utils import yaml_safe
 
 from . import eko_utils, utils
 
@@ -164,7 +164,7 @@ def load_fit(usr_path):
     nnfitpath = usr_path / "nnfit"
     pdf_dict = {}
     for yaml_file in nnfitpath.glob(f"replica_*/{usr_path.name}.exportgrid"):
-        data = yaml.safe_load(yaml_file.read_text(encoding="UTF-8"))
+        data = yaml_safe.load(yaml_file.read_text(encoding="UTF-8"))
         pdf_dict[yaml_file.parent.stem] = data
     return pdf_dict
 
diff --git a/n3fit/src/evolven3fit/utils.py b/n3fit/src/evolven3fit/utils.py
index 9f0b6ad9fd..cdd649d972 100644
--- a/n3fit/src/evolven3fit/utils.py
+++ b/n3fit/src/evolven3fit/utils.py
@@ -4,8 +4,8 @@
 import numpy as np
 from scipy.interpolate import interp1d
 
-from reportengine.compat import yaml
 from validphys.pdfbases import PIDS_DICT
+from validphys.utils import yaml_safe
 
 from .q2grids import Q2GRID_DEFAULT, Q2GRID_NNPDF40
 
@@ -57,7 +57,7 @@ def hasFlavor(self, pid):
 
 def read_runcard(usr_path):
     """Read the runcard and return the relevant information for evolven3fit"""
-    return yaml.safe_load((usr_path / "filter.yml").read_text(encoding="UTF-8"))
+    return yaml_safe.load((usr_path / "filter.yml").read_text(encoding="UTF-8"))
 
 
 def get_theoryID_from_runcard(usr_path):
@@ -99,9 +99,7 @@ def generate_q2grid(Q0, Qfin, Q_points, match_dict, nf0=None, legacy40=False):
                 frac_of_point = np.log(match_scale / Q_ini) / np.log(Qfin / Q0)
                 num_points = int(Q_points * frac_of_point)
                 num_points_list.append(num_points)
-                grids.append(
-                    np.geomspace(Q_ini**2, match_scale**2, num=num_points, endpoint=False)
-                )
+                grids.append(np.geomspace(Q_ini**2, match_scale**2, num=num_points, endpoint=False))
                 Q_ini = match_scale
         num_points = Q_points - sum(num_points_list)
         grids.append(np.geomspace(Q_ini**2, Qfin**2, num=num_points))
diff --git a/n3fit/src/n3fit/io/writer.py b/n3fit/src/n3fit/io/writer.py
index 93842d23b4..053fc6d229 100644
--- a/n3fit/src/n3fit/io/writer.py
+++ b/n3fit/src/n3fit/io/writer.py
@@ -12,8 +12,8 @@
 
 import n3fit
 from n3fit import vpinterface
-from reportengine.compat import yaml
 import validphys
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -622,4 +622,4 @@ def storefit(pdf_object, replica, out_path, theory):
     }
 
     with open(out_path, "w") as fs:
-        yaml.dump(data, fs)
+        yaml_safe.dump(data, fs)
diff --git a/n3fit/src/n3fit/scripts/n3fit_exec.py b/n3fit/src/n3fit/scripts/n3fit_exec.py
index 3f2d69559f..58942b32f4 100755
--- a/n3fit/src/n3fit/scripts/n3fit_exec.py
+++ b/n3fit/src/n3fit/scripts/n3fit_exec.py
@@ -9,14 +9,15 @@
 import re
 import shutil
 import sys
-import warnings
+
+from ruamel.yaml import error
 
 from reportengine import colors
-from reportengine.compat import yaml
 from reportengine.namespaces import NSList
 from validphys.app import App
 from validphys.config import Config, ConfigError, Environment, EnvironmentError_
 from validphys.core import FitSpec
+from validphys.utils import yaml_safe
 
 N3FIT_FIXED_CONFIG = dict(use_cuts='internal', use_t0=True, actions_=[])
 
@@ -108,15 +109,8 @@ class N3FitConfig(Config):
     @classmethod
     def from_yaml(cls, o, *args, **kwargs):
         try:
-            with warnings.catch_warnings():
-                warnings.simplefilter("ignore", yaml.error.MantissaNoDotYAML1_1Warning)
-                # We need to specify the older version 1.1 to support the
-                # older configuration files, which liked to use on/off for
-                # booleans.
-                # The floating point parsing yields warnings everywhere, which
-                # we suppress.
-                file_content = yaml.safe_load(o, version="1.1")
-        except yaml.error.YAMLError as e:
+            file_content = yaml_safe.load(o)
+        except error.YAMLError as e:
             raise ConfigError(f"Failed to parse yaml file: {e}")
         if not isinstance(file_content, dict):
             raise ConfigError(
diff --git a/n3fit/src/n3fit/scripts/vp_setupfit.py b/n3fit/src/n3fit/scripts/vp_setupfit.py
index 34de8dfea7..0739963cc1 100644
--- a/n3fit/src/n3fit/scripts/vp_setupfit.py
+++ b/n3fit/src/n3fit/scripts/vp_setupfit.py
@@ -31,12 +31,13 @@
 import re
 import shutil
 import sys
-import warnings
+
+from ruamel.yaml import error
 
 from reportengine import colors
-from reportengine.compat import yaml
 from validphys.app import App
 from validphys.config import Config, ConfigError, Environment, EnvironmentError_
+from validphys.utils import yaml_safe
 
 SETUPFIT_FIXED_CONFIG = dict(
     actions_=[
@@ -131,15 +132,8 @@ class SetupFitConfig(Config):
     @classmethod
     def from_yaml(cls, o, *args, **kwargs):
         try:
-            with warnings.catch_warnings():
-                warnings.simplefilter('ignore', yaml.error.MantissaNoDotYAML1_1Warning)
-                # We need to specify the older version 1.1 to support the
-                # older configuration files, which liked to use on/off for
-                # booleans.
-                # The floating point parsing yields warnings everywhere, which
-                # we suppress.
-                file_content = yaml.safe_load(o, version='1.1')
-        except yaml.error.YAMLError as e:
+            file_content = yaml_safe.load(o)
+        except error.YAMLError as e:
             raise ConfigError(f"Failed to parse yaml file: {e}")
         if not isinstance(file_content, dict):
             raise ConfigError(
diff --git a/n3fit/src/n3fit/tests/test_evolven3fit.py b/n3fit/src/n3fit/tests/test_evolven3fit.py
index 52799829f6..34039cb8ba 100644
--- a/n3fit/src/n3fit/tests/test_evolven3fit.py
+++ b/n3fit/src/n3fit/tests/test_evolven3fit.py
@@ -8,9 +8,9 @@
 import pytest
 
 from eko import EKO, runner
-from reportengine.compat import yaml
 from validphys.api import API
 from validphys.pdfbases import PIDS_DICT
+from validphys.utils import yaml_safe
 
 REGRESSION_FOLDER = pathlib.Path(__file__).with_name("regressions")
 log = logging.getLogger(__name__)
@@ -24,7 +24,7 @@ def assert_sorted(arr, title):
 
 def check_lhapdf_info(info_path):
     """Check the LHAPDF info file is correct"""
-    info = yaml.load(info_path.open("r", encoding="utf-8"))
+    info = yaml_safe.load(info_path.open("r", encoding="utf-8"))
 
     alphas_qs = info["AlphaS_Qs"]
     alphas = info["AlphaS_Vals"]
diff --git a/n3fit/src/n3fit/tests/test_fit.py b/n3fit/src/n3fit/tests/test_fit.py
index c6458e2d27..0610250843 100644
--- a/n3fit/src/n3fit/tests/test_fit.py
+++ b/n3fit/src/n3fit/tests/test_fit.py
@@ -22,8 +22,8 @@
 import pytest
 
 import n3fit
-from reportengine.compat import yaml
 from validphys.n3fit_data import replica_mcseed, replica_nnseed, replica_trvlseed
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 REGRESSION_FOLDER = pathlib.Path(__file__).with_name("regressions")
@@ -45,7 +45,7 @@ def _load_json(info_file):
 
 def _load_exportgrid(exportgrid_file):
     """Loads the exportgrid file"""
-    return yaml.safe_load(exportgrid_file.read_text())
+    return yaml_safe.load(exportgrid_file.read_text())
 
 
 def test_initialize_seeds():
diff --git a/nnpdf_data/nnpdf_data/__init__.py b/nnpdf_data/nnpdf_data/__init__.py
index a6eeec892d..f12d3e0abc 100644
--- a/nnpdf_data/nnpdf_data/__init__.py
+++ b/nnpdf_data/nnpdf_data/__init__.py
@@ -1,9 +1,7 @@
 from functools import lru_cache
 import pathlib
 
-import ruamel.yaml as yaml
-
-from ._version import __version__
+import yaml
 
 path_vpdata = pathlib.Path(__file__).parent
 path_commondata = path_vpdata / "commondata"
@@ -12,7 +10,8 @@
 _path_legacy_mapping = path_commondata / "dataset_names.yml"
 theory_cards = path_vpdata / "theory_cards"
 
-_legacy_to_new_mapping_raw = yaml.YAML().load(_path_legacy_mapping)
+with open(_path_legacy_mapping) as file:
+    _legacy_to_new_mapping_raw = yaml.load(file, yaml.Loader)
 # Convert strings into a dictionary
 legacy_to_new_mapping = {
     k: ({"dataset": v} if isinstance(v, str) else v) for k, v in _legacy_to_new_mapping_raw.items()
diff --git a/nnpdf_data/nnpdf_data/theory.py b/nnpdf_data/nnpdf_data/theory.py
index 558ca57306..2ce555f37e 100644
--- a/nnpdf_data/nnpdf_data/theory.py
+++ b/nnpdf_data/nnpdf_data/theory.py
@@ -4,12 +4,9 @@
 """
 
 import dataclasses
-from functools import lru_cache
 import logging
 from typing import Literal, Optional
 
-from .utils import parse_yaml_inp
-
 DEPRECATED_KEYS = ["MaxNfAs", "SxRes", "SxOrd" "EScaleVar", "Qedref", "global_nx"]
 
 log = logging.getLogger(__name__)
diff --git a/nnpdf_data/nnpdf_data/utils.py b/nnpdf_data/nnpdf_data/utils.py
index 33987134bd..b07fe4f399 100644
--- a/nnpdf_data/nnpdf_data/utils.py
+++ b/nnpdf_data/nnpdf_data/utils.py
@@ -1,8 +1,10 @@
 import pathlib
 
-import ruamel.yaml as yaml
+from ruamel.yaml import YAML
 from validobj import ValidationError, parse_input
+import yaml
 
+yaml_rt = YAML(typ="rt")
 try:
     Loader = yaml.CLoader
 except AttributeError:
@@ -22,14 +24,14 @@ def parse_yaml_inp(input_yaml, spec):
         return parse_input(inp, spec)
     except ValidationError as e:
         current_exc = e
-        # In order to provide a more complete error information, use round_trip_load
+        # In order to provide a more complete error information, use round trip
         # to read the .yaml file again (insetad of using the CLoader)
-        current_inp = yaml.round_trip_load(input_yaml.open("r", encoding="utf-8"))
+        current_inp = yaml_rt.load(input_yaml.open("r", encoding="utf-8"))
         error_text_lines = []
         while current_exc:
             if hasattr(current_exc, 'wrong_field'):
                 wrong_field = current_exc.wrong_field
-                # Mappings compping from ``round_trip_load`` have an
+                # Mappings compping from yaml_rt have an
                 # ``lc`` attribute that gives a tuple of
                 # ``(line_number, column)`` for a given item in
                 # the mapping.
diff --git a/nnpdf_data/pyproject.toml b/nnpdf_data/pyproject.toml
index 68e272ccb7..11609e12ed 100644
--- a/nnpdf_data/pyproject.toml
+++ b/nnpdf_data/pyproject.toml
@@ -33,7 +33,7 @@ include = [
 
 [tool.poetry.dependencies]
 python = "^3.9"
-"ruamel.yaml" = "<0.18"
+"ruamel.yaml" = "*"
 # Required to run filters: `filter_files_dependencies`
 pandas = {version = "*", optional = true}
 numpy = {version = "*", optional = true}
diff --git a/pyproject.toml b/pyproject.toml
index d4f135d44c..e9f4ce5d9a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -65,6 +65,7 @@ matplotlib = "^3.9"
 pineappl = "^0.8.2"
 pandas = "*"
 numpy = "*"
+"ruamel.yaml" = "*"
 validobj = "*"
 prompt_toolkit = "*"
 # Reportengine needs to be installed from git
diff --git a/validphys2/serverscripts/index-reports.py b/validphys2/serverscripts/index-reports.py
index 0c910e6b29..a48aebae62 100644
--- a/validphys2/serverscripts/index-reports.py
+++ b/validphys2/serverscripts/index-reports.py
@@ -6,20 +6,24 @@
 called meta.yaml in the report folder and finally the html
 attributes, in that order.
 """
-import pathlib
+
+from collections import ChainMap, defaultdict
 import datetime
 import json
+import pathlib
 import re
 import sys
 import traceback
-from collections import ChainMap, defaultdict
 
-import ruamel_yaml as yaml
 from bs4 import BeautifulSoup
-#TODO: Move the thumbnail logic somewhere
-import skimage.transform
-import skimage.io
 import numpy as np
+from ruamel.yaml import error
+import skimage.io
+
+# TODO: Move the thumbnail logic somewhere
+import skimage.transform
+
+from validphys.utils import yaml_safe
 
 ROOT = '/home/nnpdf/validphys-reports'
 ROOT_URL = 'https://vp.nnpdf.science/'
@@ -34,6 +38,7 @@
 
 REQUIRED_FILE_METADATA = {'title', 'author', 'keywords'}
 
+
 def meta_from_html(f):
     soup = BeautifulSoup(f, 'lxml')
     try:
@@ -41,68 +46,73 @@ def meta_from_html(f):
     except Exception:
         title = None
     try:
-        author = soup.find('meta', {'name':'author'})['content']
+        author = soup.find('meta', {'name': 'author'})['content']
     except Exception:
         author = EMPTY
 
     try:
-        tagtext = soup.find('meta', {'name':'keywords'})['content']
+        tagtext = soup.find('meta', {'name': 'keywords'})['content']
     except Exception:
         tags = []
     else:
         tags = re.split(r"\s*,\s*", tagtext)
     #'soup.title.string' doesn't
-    #return a strig but rather an object with the reference to
-    #the whole parse tree, causing a huge memory leak.
+    # return a strig but rather an object with the reference to
+    # the whole parse tree, causing a huge memory leak.
     return dict(title=str(title), author=author, keywords=tags)
 
-class TagProps():
+
+class TagProps:
     def __init__(self, count=0, last_timestamp=0):
         self.count = count
         self.last_timestamp = last_timestamp
 
     __slots__ = ('count', 'last_timestamp')
 
+
 def meta_from_path(p):
     meta = ChainMap(DEFAULTS)
-    yaml_meta = p/'meta.yaml'
+    yaml_meta = p / 'meta.yaml'
     yaml_res = {}
     if yaml_meta.exists():
         with yaml_meta.open() as f:
             try:
-                yaml_res = yaml.safe_load(f)
-            except yaml.YAMLError as e:
+                yaml_res = yaml_safe.load(f)
+            except error.YAMLError as e:
                 print(f"Error processing {yaml_meta}: {e}", file=sys.stderr)
-    index = p/'index.html'
-    #Only do the expensive HTML parsing if we actually need a key
+    index = p / 'index.html'
+    # Only do the expensive HTML parsing if we actually need a key
     if REQUIRED_FILE_METADATA - yaml_res.keys() and index.exists():
         with index.open() as f:
             meta = meta.new_child(meta_from_html(f))
     meta = meta.new_child(yaml_res)
     return meta
 
+
 def make_single_thumbnail(f, shape=(100, 150)):
     img = skimage.io.imread(f)
-    res = skimage.transform.resize(
-        img, shape, anti_aliasing=True, mode='constant')
+    res = skimage.transform.resize(img, shape, anti_aliasing=True, mode='constant')
     return res
 
+
 def make_4_img_thumbnail(paths, shape=(100, 150)):
     w, h = shape
     whalf, hhalf = w // 2, h // 2
     positions = (
-        (slice(0,whalf), slice(0,hhalf)),
-        (slice(whalf,w), slice(0,hhalf)),
-        (slice(0,whalf), slice(hhalf,h)),
-        (slice(whalf,w), slice(hhalf,h))
+        (slice(0, whalf), slice(0, hhalf)),
+        (slice(whalf, w), slice(0, hhalf)),
+        (slice(0, whalf), slice(hhalf, h)),
+        (slice(whalf, w), slice(hhalf, h)),
     )
     res = np.zeros((*shape, 4))
     imgs = skimage.io.imread_collection(paths)
     for img, pos in zip(imgs, positions):
         res[pos] = skimage.transform.resize(
-            img, (whalf, hhalf), anti_aliasing=True, mode='constant')
+            img, (whalf, hhalf), anti_aliasing=True, mode='constant'
+        )
     return res
 
+
 def make_thumbnail(folder):
     folder = pathlib.Path(folder)
     pngs = sorted(folder.glob('*.png'))
@@ -112,19 +122,20 @@ def make_thumbnail(folder):
         return make_single_thumbnail(pngs[0])
     else:
         l = len(pngs)
-        imgs = pngs[:l-(l%4):l//4]
+        imgs = pngs[: l - (l % 4) : l // 4]
         return make_4_img_thumbnail(imgs)
 
 
 def thumbnail_tag(name):
     return f'{ROOT_URL}thumbnails/{name}"'
 
+
 def handle_thumbnail(p):
     dest = (pathlib.Path(THUMBNAILS) / p.name).with_suffix('.png')
     name = dest.name
     if dest.exists():
         return thumbnail_tag(name)
-    figures = (p / 'figures')
+    figures = p / 'figures'
     if figures.is_dir():
         try:
             res = make_thumbnail(figures)
@@ -137,12 +148,13 @@ def handle_thumbnail(p):
             return None
     return None
 
+
 def register(p, emails):
     path_meta = meta_from_path(p)
     title, author, tags = path_meta['title'], path_meta['author'], path_meta['keywords']
     url = ROOT_URL + p.name
 
-    #Use the timestamp for sorting and the string for displaying
+    # Use the timestamp for sorting and the string for displaying
     timestamp = p.stat().st_mtime
     date = datetime.date.fromtimestamp(timestamp).isoformat()
     if not title or not isinstance(title, str):
@@ -155,9 +167,7 @@ def register(p, emails):
     if not isinstance(author, str):
         author = "<INVALID AUTHOR>"
 
-    emaillinks = ' '.join(
-        f'<a href="{url}", title="{title}">📧</a>' for (url, title) in emails
-    )
+    emaillinks = ' '.join(f'<a href="{url}", title="{title}">📧</a>' for (url, title) in emails)
 
     titlelink = f'<a href="{url}">{title}</a> {emaillinks}'
 
@@ -188,18 +198,17 @@ def make_index():
                 timestamp = res[2][1]
                 for k in newkeywords:
                     props = keywords[k]
-                    props.count+=1
+                    props.count += 1
                     props.last_timestamp = max(props.last_timestamp, timestamp)
             except:
-                print("Error processing folder", p,file=sys.stderr)
+                print("Error processing folder", p, file=sys.stderr)
                 raise
 
     keylist = sorted(keywords.items(), key=lambda x: -x[1].last_timestamp)
-    keywordmap = [(k, v.count) for k,v in keylist]
-
+    keywordmap = [(k, v.count) for k, v in keylist]
 
     with open(OUT, 'w') as f:
-        json.dump({'data':data, 'keywords':keywordmap}, f)
+        json.dump({'data': data, 'keywords': keywordmap}, f)
 
 
 if __name__ == '__main__':
diff --git a/validphys2/src/validphys/commondataparser.py b/validphys2/src/validphys/commondataparser.py
index 7e4875d997..b63dce6d97 100644
--- a/validphys2/src/validphys/commondataparser.py
+++ b/validphys2/src/validphys/commondataparser.py
@@ -41,7 +41,7 @@
 import logging
 from operator import attrgetter
 from pathlib import Path
-from typing import Any, Dict, Optional
+from typing import Any, Optional
 
 import numpy as np
 import pandas as pd
@@ -50,27 +50,10 @@
 
 from nnpdf_data import new_to_legacy_map, path_commondata
 from nnpdf_data.utils import parse_yaml_inp
-
-# We cannot use ruamel directly due to the ambiguity ruamel.yaml / ruamel_yaml
-# of some versions which are pinned in some of the conda packages we use...
-from reportengine.compat import yaml
 from validphys.coredata import KIN_NAMES, CommonData
 from validphys.plotoptions.plottingoptions import PlottingOptions, labeler_functions
 from validphys.process_options import ValidProcess
-
-try:
-    # If libyaml is available, use the C loader to speed up some of the read
-    # https://pyyaml.org/wiki/LibYAML
-    # libyaml is available for most linux distributions
-    Loader = yaml.CLoader
-except AttributeError:
-    # fallback to the slow loader
-    Loader = yaml.Loader
-
-
-def _quick_yaml_load(filepath):
-    return yaml.load(filepath.read_text(encoding="utf-8"), Loader=Loader)
-
+from validphys.utils import yaml_fast
 
 # JCM:
 # Some notes for developers
@@ -230,7 +213,7 @@ class TheoryMeta:
     -------
     >>> from validphys.commondataparser import TheoryMeta
     ... from validobj import parse_input
-    ... from reportengine.compat import yaml
+    ... from ruamel.yaml import YAML
     ... theory_raw = '''
     ... FK_tables:
     ...   - - fk1
@@ -238,7 +221,7 @@ class TheoryMeta:
     ...     - fk3
     ... operation: ratio
     ... '''
-    ... theory = yaml.safe_load(theory_raw)
+    ... theory = YAML(typ='safe').load(theory_raw)
     ... parse_input(theory, TheoryMeta)
     TheoryMeta(FK_tables=[['fk1'], ['fk2', 'fk3']], operation='RATIO', shifts = None, conversion_factor=1.0, comment=None, normalization=None))
     """
@@ -263,7 +246,7 @@ def parser(cls, yaml_file):
         """The yaml databases in the server use "operands" as key instead of "FK_tables" """
         if not yaml_file.exists():
             raise FileNotFoundError(yaml_file)
-        meta = yaml.safe_load(yaml_file.read_text())
+        meta = yaml_fast.load(yaml_file.read_text())
         # Make sure the operations are upper-cased for compound-compatibility
         meta["operation"] = "NULL" if meta["operation"] is None else meta["operation"].upper()
         if "operands" in meta:
@@ -309,7 +292,7 @@ class Variant:
     experiment: Optional[str] = None
 
 
-ValidVariants = Dict[str, Variant]
+ValidVariants = dict[str, Variant]
 
 
 ### Kinematic data
@@ -351,7 +334,7 @@ class ValidKinematics:
     """
 
     file: ValidPath
-    variables: Dict[str, ValidVariable]
+    variables: dict[str, ValidVariable]
 
     def get_label(self, var):
         """For the given variable, return the label as label (unit)
@@ -523,7 +506,7 @@ def load_data_central(self):
         if self.is_nnpdf_special:
             data = np.zeros(self.ndata)
         else:
-            datayaml = _quick_yaml_load(self.path_data_central)
+            datayaml = yaml_fast.load(self.path_data_central)
             data = datayaml["data_central"]
 
         if len(data) != self.ndata:
@@ -552,8 +535,7 @@ def load_uncertainties(self):
 
         all_df = []
         for ufile in self.paths_uncertainties:
-            uncyaml = _quick_yaml_load(ufile)
-
+            uncyaml = yaml_fast.load(ufile)
             mindex = pd.MultiIndex.from_tuples(
                 [(k, v["treatment"], v["type"]) for k, v in uncyaml["definitions"].items()],
                 names=["name", "treatment", "type"],
@@ -589,7 +571,7 @@ def load_kinematics(self, fill_to_three=True, drop_minmax=True):
             a dataframe containing the kinematics
         """
         kinematics_file = self.path_kinematics
-        kinyaml = _quick_yaml_load(kinematics_file)
+        kinyaml = yaml_fast.load(kinematics_file)
 
         kin_dict = {}
         for bin_index, dbin in enumerate(kinyaml["bins"], start=1):
diff --git a/validphys2/src/validphys/config.py b/validphys2/src/validphys/config.py
index 1c814af690..10e4f009f5 100644
--- a/validphys2/src/validphys/config.py
+++ b/validphys2/src/validphys/config.py
@@ -12,7 +12,6 @@
 
 from nnpdf_data import legacy_to_new_map
 from reportengine import configparser, report
-from reportengine.compat import yaml
 from reportengine.configparser import ConfigError, _parse_func, element_of, record_from_defaults
 from reportengine.environment import Environment, EnvironmentError_
 from reportengine.helputils import get_parser_type
@@ -48,6 +47,7 @@
 )
 from validphys.plotoptions.core import get_info
 import validphys.scalevariations
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -1289,7 +1289,7 @@ def load_default_default_filter_rules(self, spec):
 
         lock_token = "_filters.lock.yaml"
         try:
-            return yaml.safe_load(read_text(validphys.cuts.lockfiles, f"{spec}{lock_token}"))
+            return yaml_safe.load(read_text(validphys.cuts.lockfiles, f"{spec}{lock_token}"))
         except FileNotFoundError as e:
             alternatives = [
                 el.strip(lock_token)
@@ -1386,7 +1386,7 @@ def load_default_default_filter_settings(self, spec):
 
         lock_token = "_defaults.lock.yaml"
         try:
-            return yaml.safe_load(read_text(validphys.cuts.lockfiles, f"{spec}{lock_token}"))
+            return yaml.load(read_text(validphys.cuts.lockfiles, f"{spec}{lock_token}"))
         except FileNotFoundError as e:
             alternatives = alternatives = [
                 el.strip(lock_token)
@@ -1663,7 +1663,7 @@ def produce_theoryids(self, t0id, point_prescription):
         This hard codes the theories needed for each prescription to avoid user error."""
         th = t0id.id
 
-        lsv = yaml.safe_load(read_text(validphys.scalevariations, "scalevariationtheoryids.yaml"))
+        lsv = yaml_safe.load(read_text(validphys.scalevariations, "scalevariationtheoryids.yaml"))
 
         scalevarsfor_list = lsv["scale_variations_for"]
         # Allowed central theoryids
@@ -1677,7 +1677,7 @@ def produce_theoryids(self, t0id, point_prescription):
             )
 
         # Find scales that correspond to this point prescription
-        pp_scales_dict = yaml.safe_load(
+        pp_scales_dict = yaml_safe.load(
             read_text(validphys.scalevariations, "pointprescriptions.yaml")
         )
 
diff --git a/validphys2/src/validphys/core.py b/validphys2/src/validphys/core.py
index dc1d880513..ceb0343feb 100644
--- a/validphys2/src/validphys/core.py
+++ b/validphys2/src/validphys/core.py
@@ -12,11 +12,11 @@
 import re
 
 import numpy as np
+from ruamel.yaml import error
 
 from nnpdf_data.theorydbutils import fetch_theory
 from reportengine import namespaces
 from reportengine.baseexceptions import AsInputError
-from reportengine.compat import yaml
 
 # TODO: There is a bit of a circular dependency between filters.py and this.
 # Maybe move the cuts logic to its own module?
@@ -26,7 +26,7 @@
 from validphys.hyperoptplot import HyperoptTrial
 from validphys.lhapdfset import LHAPDFSet
 from validphys.tableloader import parse_exp_mat
-from validphys.utils import experiments_to_dataset_inputs
+from validphys.utils import experiments_to_dataset_inputs, yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -713,8 +713,8 @@ def as_input(self):
         log.debug('Reading input from fit configuration %s', p)
         try:
             with p.open() as f:
-                d = yaml.safe_load(f)
-        except (yaml.YAMLError, FileNotFoundError) as e:
+                d = yaml_safe.load(f)
+        except (error.YAMLError, FileNotFoundError) as e:
             raise AsInputError(str(e)) from e
         d['pdf'] = {'id': self.name, 'label': self.label}
 
diff --git a/validphys2/src/validphys/coredata.py b/validphys2/src/validphys/coredata.py
index 46a1cab7c6..371f9837b1 100644
--- a/validphys2/src/validphys/coredata.py
+++ b/validphys2/src/validphys/coredata.py
@@ -10,8 +10,7 @@
 import numpy as np
 import pandas as pd
 
-from reportengine.compat import yaml
-from validphys.utils import generate_path_filtered_data
+from validphys.utils import generate_path_filtered_data, yaml_safe
 
 KIN_NAMES = ["kin1", "kin2", "kin3"]
 log = logging.getLogger(__name__)
@@ -431,7 +430,7 @@ def systematic_errors(self, central_values=None):
     def export_data(self, buffer):
         """Exports the central data defined by this commondata instance to the given buffer"""
         ret = {"data_central": self.central_values.tolist()}
-        yaml.safe_dump(ret, buffer)
+        yaml_safe.dump(ret, buffer)
 
     def export_uncertainties(self, buffer):
         """Exports the uncertainties defined by this commondata instance to the given buffer"""
@@ -460,7 +459,7 @@ def export_uncertainties(self, buffer):
             "type": "UNCORR",
         }
         ret = {"definitions": sorted_definitions, "bins": bins}
-        yaml.safe_dump(ret, buffer)
+        yaml_safe.dump(ret, buffer)
 
     def export(self, folder_path):
         """Wrapper around export_data and export_uncertainties
@@ -473,6 +472,8 @@ def export(self, folder_path):
         data_path = folder_path / data_path.name
         unc_path = folder_path / unc_path.name
         # Export data and uncertainties
-        self.export_data(data_path.open("w", encoding="utf-8"))
-        self.export_uncertainties(unc_path.open("w", encoding="utf-8"))
+        with open(data_path, "w") as file:
+            self.export_data(file)
+        with open(unc_path, "w") as file:
+            self.export_uncertainties(file)
         return data_path, unc_path
diff --git a/validphys2/src/validphys/eff_exponents.py b/validphys2/src/validphys/eff_exponents.py
index 0837b06b3d..00ac155479 100644
--- a/validphys2/src/validphys/eff_exponents.py
+++ b/validphys2/src/validphys/eff_exponents.py
@@ -1,12 +1,12 @@
-# -*- coding: utf-8 -*-
 """
 Tools for computing and plotting effective exponents.
 """
-from __future__ import generator_stop
 
 import logging
 import numbers
+from pathlib import Path
 import random
+import tempfile
 import warnings
 
 import matplotlib as mpl
@@ -15,7 +15,6 @@
 
 from reportengine import collect
 from reportengine.checks import check_positive
-from reportengine.compat import yaml
 from reportengine.figure import figuregen
 from reportengine.floatformatting import format_number, significant_digits
 from reportengine.table import table
@@ -24,6 +23,7 @@
 from validphys.pdfbases import Basis, check_basis
 import validphys.pdfgrids as pdfgrids
 from validphys.pdfplots import BandPDFPlotter, PDFPlotter
+from validphys.utils import yaml_rt
 
 log = logging.getLogger(__name__)
 
@@ -139,7 +139,7 @@ def get_title(self, parton_name):
 
     def get_ylabel(self, parton_name):
         if self.normalize_to is not None:
-            return "Ratio to {}".format(self.normalize_pdf.label)
+            return f"Ratio to {self.normalize_pdf.label}"
         else:
             return fr"$\{self.exponent}_e$ for ${parton_name}$"
 
@@ -502,8 +502,8 @@ def iterate_preprocessing_yaml(fit, next_fit_eff_exps_table, _flmap_np_clip_arg=
     """
     (df_effexps,) = next_fit_eff_exps_table
     # Use round trip loader rather than safe_load in fit.as_input()
-    with open(fit.path / "filter.yml", "r") as f:
-        filtermap = yaml.load(f, yaml.RoundTripLoader)
+    with open(fit.path / "filter.yml") as f:
+        filtermap = yaml_rt.load(f)
     previous_exponents = filtermap["fitting"]["basis"]
     basis = filtermap["fitting"]["fitbasis"]
     checked = check_basis(basis, None)
@@ -524,7 +524,11 @@ def iterate_preprocessing_yaml(fit, next_fit_eff_exps_table, _flmap_np_clip_arg=
                 betas = np.clip(betas, **largex_args)
         previous_exponents[i]["smallx"] = [fmt(alpha) for alpha in alphas]
         previous_exponents[i]["largex"] = [fmt(beta) for beta in betas]
-    return yaml.dump(filtermap, Dumper=yaml.RoundTripDumper)
+    with tempfile.NamedTemporaryFile() as fp:
+        path = Path(fp.name)
+        yaml_rt.dump(filtermap, path)
+        yaml_string = fp.read().decode("utf-8")
+    return yaml_string
 
 
 def update_runcard_description_yaml(iterate_preprocessing_yaml, _updated_description=None):
@@ -539,13 +543,18 @@ def update_runcard_description_yaml(iterate_preprocessing_yaml, _updated_descrip
     ```
 
     """
-    filtermap = yaml.load(iterate_preprocessing_yaml, yaml.RoundTripLoader)
+    filtermap = yaml_rt.load(iterate_preprocessing_yaml)
 
     # update description if necessary
     if _updated_description is not None:
         filtermap["description"] = _updated_description
 
-    return yaml.dump(filtermap, Dumper=yaml.RoundTripDumper)
+    with tempfile.NamedTemporaryFile() as fp:
+        path = Path(fp.name)
+        yaml_rt.dump(filtermap, path)
+        yaml_string = fp.read().decode("utf-8")
+
+    return yaml_string
 
 
 def iterated_runcard_yaml(fit, update_runcard_description_yaml):
@@ -578,7 +587,7 @@ def iterated_runcard_yaml(fit, update_runcard_description_yaml):
     ...     f.write(yaml_output)
 
     """
-    filtermap = yaml.load(update_runcard_description_yaml, yaml.RoundTripLoader)
+    filtermap = yaml_rt.load(update_runcard_description_yaml)
     # iterate t0
     filtermap["datacuts"]["t0pdfset"] = fit.name
 
@@ -605,4 +614,9 @@ def iterated_runcard_yaml(fit, update_runcard_description_yaml):
     if "fiatlux" in filtermap:
         filtermap['fiatlux']['luxset'] = fit.name
 
-    return yaml.dump(filtermap, Dumper=yaml.RoundTripDumper)
+    with tempfile.NamedTemporaryFile() as fp:
+        path = Path(fp.name)
+        yaml_rt.dump(filtermap, path)
+        yaml_string = fp.read().decode("utf-8")
+
+    return yaml_string
diff --git a/validphys2/src/validphys/filters.py b/validphys2/src/validphys/filters.py
index 944d11c5cb..df698ca34d 100644
--- a/validphys2/src/validphys/filters.py
+++ b/validphys2/src/validphys/filters.py
@@ -13,10 +13,9 @@
 import numpy as np
 
 from reportengine.checks import check, make_check
-from reportengine.compat import yaml
 import validphys.cuts
 from validphys.process_options import PROCESSES
-from validphys.utils import generate_path_filtered_data
+from validphys.utils import generate_path_filtered_data, yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -156,7 +155,7 @@ def default_filter_settings_input():
     """Return a FilterDefaults dataclass with the default hardcoded filter settings.
     These are defined in ``defaults.yaml`` in the ``validphys.cuts`` module.
     """
-    return FilterDefaults(**yaml.safe_load(read_text(validphys.cuts, "defaults.yaml")))
+    return FilterDefaults(**yaml_safe.load(read_text(validphys.cuts, "defaults.yaml")))
 
 
 def default_filter_rules_input():
@@ -164,7 +163,7 @@ def default_filter_rules_input():
     Return a tuple of FilterRule objects.
     These are defined in ``filters.yaml`` in the ``validphys.cuts`` module.
     """
-    list_rules = yaml.safe_load(read_text(validphys.cuts, "filters.yaml"))
+    list_rules = yaml_safe.load(read_text(validphys.cuts, "filters.yaml"))
     return tuple(FilterRule(**rule) for rule in list_rules)
 
 
diff --git a/validphys2/src/validphys/fitdata.py b/validphys2/src/validphys/fitdata.py
index d87138a2e2..8bd4c5eae0 100644
--- a/validphys2/src/validphys/fitdata.py
+++ b/validphys2/src/validphys/fitdata.py
@@ -1,6 +1,7 @@
 """
 Utilities for loading data from fit folders
 """
+
 from collections import OrderedDict, defaultdict, namedtuple
 from io import StringIO
 import json
@@ -12,12 +13,12 @@
 
 from reportengine import collect
 from reportengine.checks import CheckError, make_argcheck
-from reportengine.compat import yaml
 from reportengine.floatformatting import ValueErrorTuple
 from reportengine.table import table
 from validphys import checks
 from validphys.core import PDF
 from validphys.plotoptions.core import get_info
+from validphys.utils import yaml_safe
 
 # TODO: Add more stuff here as needed for postfit
 LITERAL_FILES = ['chi2exps.log']
@@ -431,7 +432,7 @@ def _get_fitted_index(pdf, i):
     """Return the nnfit index for the replica i"""
     p = pdf.infopath.with_name(f'{pdf.name}_{i:04d}.dat')
     with open(p) as f:
-        it = yaml.safe_load_all(f)
+        it = yaml_safe.load_all(f)
         metadata = next(it)
     return metadata['FromMCReplica']
 
diff --git a/validphys2/src/validphys/lhaindex.py b/validphys2/src/validphys/lhaindex.py
index 9a10d66ff1..6b4ee00db0 100644
--- a/validphys2/src/validphys/lhaindex.py
+++ b/validphys2/src/validphys/lhaindex.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 #!/usr/bin/env python
 """
 Created on Fri Jan 23 12:11:23 2015
@@ -13,8 +12,8 @@
 from pathlib import Path
 import re
 
-from reportengine.compat import yaml
 from validphys.lhapdf_compatibility import lhapdf
+from validphys.utils import yaml_safe
 
 _indexes_to_names = None
 _names_to_indexes = None
@@ -123,10 +122,10 @@ def infofilename(name):
     raise FileNotFoundError(name + ".info")
 
 
-@lru_cache()
+@lru_cache
 def parse_info(name):
     with open(infofilename(name)) as infofile:
-        result = yaml.YAML(typ='safe', pure=True).load(infofile)
+        result = yaml_safe.load(infofile)
     return result
 
 
diff --git a/validphys2/src/validphys/lhio.py b/validphys2/src/validphys/lhio.py
index 92c767cccc..d0d8f9d861 100644
--- a/validphys2/src/validphys/lhio.py
+++ b/validphys2/src/validphys/lhio.py
@@ -11,9 +11,9 @@
 import numpy as np
 import pandas as pd
 
-from reportengine.compat import yaml
 from validphys import lhaindex
 from validphys.core import PDF
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -28,8 +28,8 @@ def split_sep(f):
 def read_xqf_from_file(f):
     lines = split_sep(f)
     try:
-        (xtext, qtext, ftext) = [next(lines) for _ in range(3)]
-    except StopIteration:
+        (xtext, qtext, ftext) = (next(lines) for _ in range(3))
+    except RuntimeError:
         return None
     xvals = np.fromstring(xtext, sep=" ")
     qvals = np.fromstring(qtext, sep=" ")
@@ -69,7 +69,7 @@ def load_replica(pdf, rep, kin_grids=None):
 
     path = osp.join(lhaindex.finddir(pdf_name), pdf_name + "_" + suffix + ".dat")
 
-    log.debug("Loading replica {rep} at {path}".format(rep=rep, path=path))
+    log.debug(f"Loading replica {rep} at {path}")
 
     with open(path, 'rb') as inn:
         header = b"".join(split_sep(inn))
@@ -315,7 +315,7 @@ def hessian_from_lincomb(pdf, V, set_name=None, folder=None, extra_fields=None):
     # copy replica 0
     shutil.copy(base / f'{pdf}_0000.dat', set_root / f"{set_name }_0000.dat")
 
-    with open(base / f'{pdf}.info', 'r') as inn, open(set_root / f'{set_name }.info', 'w') as out:
+    with open(base / f'{pdf}.info') as inn, open(set_root / f'{set_name }.info', 'w') as out:
         for l in inn.readlines():
             if l.find("SetDesc:") >= 0:
                 out.write(f"SetDesc: \"Hessian {pdf}_hessian\"\n")
@@ -326,7 +326,8 @@ def hessian_from_lincomb(pdf, V, set_name=None, folder=None, extra_fields=None):
             else:
                 out.write(l)
         if extra_fields is not None:
-            yaml.dump(extra_fields, out, default_flow_style=False)
+            yaml_safe.default_flow_style = False
+            yaml_safe.dump(extra_fields, out)
 
     _headers, grids = load_all_replicas(pdf)
     result = (big_matrix(grids).dot(V)).add(grids[0], axis=0)
diff --git a/validphys2/src/validphys/loader.py b/validphys2/src/validphys/loader.py
index 230c26b076..e8312b6c10 100644
--- a/validphys2/src/validphys/loader.py
+++ b/validphys2/src/validphys/loader.py
@@ -20,7 +20,6 @@
 
 from nnpdf_data import legacy_to_new_mapping, path_vpdata
 from reportengine import filefinder
-from reportengine.compat import yaml
 from validphys import lhaindex
 from validphys.commondataparser import load_commondata_old, parse_new_metadata, parse_set_metadata
 from validphys.core import (
@@ -37,9 +36,8 @@
     InternalCutsWrapper,
     PositivitySetSpec,
     TheoryIDSpec,
-    peek_commondata_metadata,
 )
-from validphys.utils import generate_path_filtered_data, tempfile_cleaner
+from validphys.utils import generate_path_filtered_data, tempfile_cleaner, yaml_safe
 
 log = logging.getLogger(__name__)
 NNPDF_DIR = "NNPDF"
@@ -132,14 +130,13 @@ def _get_nnpdf_profile(profile_path=None):
     the python prefix (``Path(sys.prefix)/"share"/"NNPDF"``) will be used
 
     """
-    yaml_reader = yaml.YAML(typ='safe', pure=True)
 
     home_config = pathlib.Path().home() / ".config"
     config_folder = pathlib.Path(os.environ.get("XDG_CONFIG_HOME", home_config)) / NNPDF_DIR
 
     # Set all default values
     profile_content = pkgutil.get_data("validphys", "nnprofile_default.yaml")
-    profile_dict = yaml_reader.load(profile_content)
+    profile_dict = yaml_safe.load(profile_content)
     # including the data_path to the validphys package
     profile_dict.setdefault("data_path", path_vpdata)
 
@@ -156,7 +153,7 @@ def _get_nnpdf_profile(profile_path=None):
 
     if profile_path is not None:
         with open(profile_path, encoding="utf-8") as f:
-            profile_entries = yaml_reader.load(f)
+            profile_entries = yaml_safe.load(f)
             if profile_entries is not None:
                 profile_dict.update(profile_entries)
 
@@ -423,7 +420,12 @@ def check_commondata(
                         )
                         break
                     # try new commondata format
-                    old_path = fit.path / "filter" / legacy_name / f"filtered_uncertainties_{legacy_name}.yaml"
+                    old_path = (
+                        fit.path
+                        / "filter"
+                        / legacy_name
+                        / f"filtered_uncertainties_{legacy_name}.yaml"
+                    )
                     if old_path.exists():
                         data_path = old_path.with_name(f"filtered_data_{legacy_name}.yaml")
                         unc_path = old_path.with_name(f"filtered_uncertainties_{legacy_name}.yaml")
@@ -533,7 +535,7 @@ def check_compound(self, theoryID, setname, cfac):
             raise CompoundNotFound(msg)
         # This is a little bit funny, but is the least amount of thinking...
         yaml_format = 'FK:\n' + re.sub('FK:', ' - ', txt)
-        data = yaml.safe_load(yaml_format)
+        data = yaml_safe.load(yaml_format)
         # we have to split out 'FK_' the extension to get a name consistent
         # with everything else
         try:
diff --git a/validphys2/src/validphys/photon/compute.py b/validphys2/src/validphys/photon/compute.py
index 32ef57f388..6466c4ddb7 100644
--- a/validphys2/src/validphys/photon/compute.py
+++ b/validphys2/src/validphys/photon/compute.py
@@ -122,8 +122,7 @@ def __init__(self, theoryid, lux_params, replicas):
             alpha = Alpha(theory, fiatlux_runcard["q2_max"])
 
             with tempfile.NamedTemporaryFile(mode="w") as tmp:
-                with tmp.file as tmp_file:
-                    tmp_file.write(yaml.dump(fiatlux_runcard))
+                yaml.dump(fiatlux_runcard, tmp)
                 self.lux[replica] = fiatlux.FiatLux(tmp.name)
             # we have a dict but fiatlux wants a yaml file
             # TODO : once that fiatlux will allow dictionaries
diff --git a/validphys2/src/validphys/replica_selector.py b/validphys2/src/validphys/replica_selector.py
index e636d81531..5eaca0c9cb 100644
--- a/validphys2/src/validphys/replica_selector.py
+++ b/validphys2/src/validphys/replica_selector.py
@@ -3,15 +3,15 @@
 
 Tools for filtering replica sets based on criteria on the replicas.
 """
+
 import logging
 import re
 import shutil
 
 from reportengine.checks import check, make_argcheck
-from reportengine.compat import yaml
 from validphys.core import PDF
 from validphys.renametools import rename_pdf
-from validphys.utils import tempfile_cleaner
+from validphys.utils import tempfile_cleaner, yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -96,9 +96,8 @@ def alpha_s_bundle_pdf(pdf, pdfs, output_path, target_name: (str, type(None)) =
         #  Fixup the info file
         info_file = (temp_pdf / temp_pdf.name).with_suffix('.info')
 
-        with open(info_file, 'r') as stream:
-            yaml_obj = yaml.YAML()
-            info_yaml = yaml_obj.load(stream)
+        with open(info_file) as stream:
+            info_yaml = yaml_safe.load(stream)
         info_yaml['NumMembers'] = new_nrep
         info_yaml['ErrorType'] += '+as'
         extra_desc = '; '.join(
@@ -106,7 +105,7 @@ def alpha_s_bundle_pdf(pdf, pdfs, output_path, target_name: (str, type(None)) =
         )
         info_yaml['SetDesc'] += f"; {extra_desc}"
         with open(info_file, 'w') as stream:
-            yaml_obj.dump(info_yaml, stream)
+            yaml_safe.dump(info_yaml, stream)
 
         # Rename the base pdf to the final name
         rename_pdf(temp_pdf, pdf.name, target_name)
diff --git a/validphys2/src/validphys/scripts/vp_comparefits.py b/validphys2/src/validphys/scripts/vp_comparefits.py
index 7c79a7c05e..eb2251038a 100644
--- a/validphys2/src/validphys/scripts/vp_comparefits.py
+++ b/validphys2/src/validphys/scripts/vp_comparefits.py
@@ -1,18 +1,17 @@
-import sys
-import os
 import logging
+import os
+import sys
 
 # TODO: Look into making these lazy imports
 import prompt_toolkit
 from prompt_toolkit.completion import WordCompleter
 
-from reportengine.compat import yaml
 from reportengine.colors import t
-
+from validphys import compareclosuretemplates, comparefittemplates
 from validphys.app import App
 from validphys.loader import RemoteLoader
-from validphys import comparefittemplates, compareclosuretemplates
-from validphys.promptutils import confirm, KeywordsWithCache
+from validphys.promptutils import KeywordsWithCache, confirm
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -241,7 +240,7 @@ def get_config(self):
         with open(self.args['config_yml']) as f:
             # TODO: Ideally this would load round trip but needs
             # to be fixed in reportengine.
-            c = yaml.safe_load(f)
+            c = yaml_safe.load(f)
         c.update(self.complete_mapping())
         return self.config_class(c, environment=self.environment)
 
diff --git a/validphys2/src/validphys/scripts/vp_deltachi2.py b/validphys2/src/validphys/scripts/vp_deltachi2.py
index 8762ede5c3..41ca8543eb 100644
--- a/validphys2/src/validphys/scripts/vp_deltachi2.py
+++ b/validphys2/src/validphys/scripts/vp_deltachi2.py
@@ -2,27 +2,19 @@
 import os
 import pwd
 
-from reportengine.compat import yaml
-
 from validphys import deltachi2templates
 from validphys.app import App
-
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
 
 class HyperoptPlotApp(App):
     def add_positional_arguments(self, parser):
-        """ Wrapper around argumentparser """
-        parser.add_argument(
-            "fit", help="Name of the fit",
-        )
-        parser.add_argument(
-            "hessian_pdfs", help="Name of the set of Hessian pdfs",
-        )
-        parser.add_argument(
-            "--Q", help="Energy Scale in GeV", type=float, default=1.7,
-        )
+        """Wrapper around argumentparser"""
+        parser.add_argument("fit", help="Name of the fit")
+        parser.add_argument("hessian_pdfs", help="Name of the set of Hessian pdfs")
+        parser.add_argument("--Q", help="Energy Scale in GeV", type=float, default=1.7)
         # Report meta data
         parser.add_argument(
             "--author",
@@ -30,9 +22,7 @@ def add_positional_arguments(self, parser):
             type=str,
             default=pwd.getpwuid(os.getuid())[4].replace(",", ""),
         )
-        parser.add_argument(
-            "--title", help="Add custom title to the report's meta data", type=str,
-        )
+        parser.add_argument("--title", help="Add custom title to the report's meta data", type=str)
         parser.add_argument(
             "--keywords",
             help="Add keywords to the report's meta data. The keywords must be provided as a list",
@@ -67,14 +57,8 @@ def complete_mapping(self):
             "normalize_to": fit,
         }
 
-        autosettings["decomposition"] = {
-            "normalize_to": hessian_pdfs,
-            "pdf": hessian_pdfs,
-        }
-        autosettings["MC_Hessian_compare"] = {
-            "pdfs": [hessian_pdfs, fit],
-            "normalize_to": fit,
-        }
+        autosettings["decomposition"] = {"normalize_to": hessian_pdfs, "pdf": hessian_pdfs}
+        autosettings["MC_Hessian_compare"] = {"pdfs": [hessian_pdfs, fit], "normalize_to": fit}
 
         return autosettings
 
@@ -85,7 +69,7 @@ def get_config(self):
         with open(runcard) as f:
             # TODO: Ideally this would load round trip but needs
             # to be fixed in reportengine.
-            c = yaml.safe_load(f)
+            c = yaml_safe.load(f)
         c.update(complete_mapping)
         return self.config_class(c, environment=self.environment)
 
diff --git a/validphys2/src/validphys/scripts/vp_hyperoptplot.py b/validphys2/src/validphys/scripts/vp_hyperoptplot.py
index 1faa875070..0d767f2aa8 100644
--- a/validphys2/src/validphys/scripts/vp_hyperoptplot.py
+++ b/validphys2/src/validphys/scripts/vp_hyperoptplot.py
@@ -1,22 +1,21 @@
-from validphys.app import App
-from validphys.loader import Loader, HyperscanNotFound
-from validphys import hyperplottemplates
-from reportengine.compat import yaml
-import pwd
+import logging
 import os
+import pwd
 
-import logging
+from validphys import hyperplottemplates
+from validphys.app import App
+from validphys.loader import HyperscanNotFound, Loader
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
 
 class HyperoptPlotApp(App):
     def add_positional_arguments(self, parser):
-        """ Wrapper around argumentparser """
+        """Wrapper around argumentparser"""
         # Hyperopt settings
         parser.add_argument(
-            "hyperopt_name",
-            help="Folder of the hyperopt fit to generate the report for",
+            "hyperopt_name", help="Folder of the hyperopt fit to generate the report for"
         )
         parser.add_argument(
             "-l",
@@ -73,16 +72,12 @@ def add_positional_arguments(self, parser):
             type=str,
             default=pwd.getpwuid(os.getuid())[4].replace(",", ""),
         )
-        parser.add_argument(
-            "--title",
-            help="Add custom title to the report's meta data",
-            type=str,
-        )
+        parser.add_argument("--title", help="Add custom title to the report's meta data", type=str)
         parser.add_argument(
             "--keywords",
             help="Add keywords to the report's meta data. The keywords must be provided as a list",
             type=list,
-            default=[]
+            default=[],
         )
         args = parser.parse_args()
 
@@ -104,7 +99,7 @@ def complete_mapping(self):
             hyperop_folder = hyperop_folder[:-1]
 
         with open(hyperopt_filter) as f:
-            filtercard = yaml.safe_load(f)
+            filtercard = yaml_safe.load(f)
 
         folder_path = hyperop_folder
         index_slash = folder_path.rfind("/") + 1
@@ -127,7 +122,7 @@ def complete_mapping(self):
             "combine": args["combine"],
             "autofilter": args["autofilter"],
             "debug": args["debug"],
-            "loss_target": args["loss_target"]
+            "loss_target": args["loss_target"],
         }
 
         try:
@@ -148,7 +143,7 @@ def get_config(self):
         with open(self.args['config_yml']) as f:
             # TODO: Ideally this would load round trip but needs
             # to be fixed in reportengine.
-            c = yaml.safe_load(f)
+            c = yaml_safe.load(f)
         c.update(self.complete_mapping())
         return self.config_class(c, environment=self.environment)
 
diff --git a/validphys2/src/validphys/scripts/vp_nextfitruncard.py b/validphys2/src/validphys/scripts/vp_nextfitruncard.py
index ecf379e014..03eeeddb6a 100644
--- a/validphys2/src/validphys/scripts/vp_nextfitruncard.py
+++ b/validphys2/src/validphys/scripts/vp_nextfitruncard.py
@@ -16,16 +16,16 @@
 """
 
 import argparse
+import logging
 import os
 import pathlib
 import sys
-import logging
+
 import prompt_toolkit
 
 from reportengine import colors
-from reportengine.compat import yaml
-
 from validphys.api import API
+from validphys.utils import yaml_safe
 
 # arguments for np.clip to enforce integrability.
 # key should be identical to runcard key, first inner dictionary can contain
@@ -40,11 +40,10 @@
     "t8": {"smallx": {"a_min": None, "a_max": 1.0}},
 }
 
+
 # Take command line arguments
 def process_args():
-    parser = argparse.ArgumentParser(
-        description="Script to generate iterated fit runcard."
-    )
+    parser = argparse.ArgumentParser(description="Script to generate iterated fit runcard.")
     parser.add_argument("input_fit", help="Name of input fit.")
     parser.add_argument(
         "output_dir",
@@ -65,7 +64,7 @@ def process_args():
             "Do not enforce any preprocessing constraints, which are chosen to "
             "ensure integrability. By default the following constraints are "
             f"used: {PREPROCESSING_LIMS}"
-        )
+        ),
     )
     args = parser.parse_args()
     return args
@@ -125,7 +124,7 @@ def main():
         preproc_lims = PREPROCESSING_LIMS
         log.info(
             "The following constraints will be used for preprocessing ranges, \n%s",
-            yaml.dump(preproc_lims),
+            yaml_safe.dump(preproc_lims, sys.stdout),
         )
     else:
         # don't enforce any limits.
@@ -134,9 +133,7 @@ def main():
     updated_description = interactive_description(description)
 
     iterated_runcard_yaml = API.iterated_runcard_yaml(
-        fit=input_fit,
-        _updated_description=updated_description,
-        _flmap_np_clip_arg=preproc_lims,
+        fit=input_fit, _updated_description=updated_description, _flmap_np_clip_arg=preproc_lims
     )
 
     # Write new runcard to file
diff --git a/validphys2/src/validphys/scripts/vp_pdffromreplicas.py b/validphys2/src/validphys/scripts/vp_pdffromreplicas.py
index e68df56dcc..4c87e8584a 100755
--- a/validphys2/src/validphys/scripts/vp_pdffromreplicas.py
+++ b/validphys2/src/validphys/scripts/vp_pdffromreplicas.py
@@ -27,13 +27,12 @@
 import tempfile
 
 import pandas as pd
-from reportengine import colors
-from reportengine.compat import yaml
 
+from reportengine import colors
 from validphys import lhaindex
 from validphys.lhio import new_pdf_from_indexes
 from validphys.loader import FallbackLoader
-
+from validphys.utils import yaml_safe
 
 log = logging.getLogger()
 log.setLevel(logging.INFO)
@@ -53,9 +52,7 @@ def check_none_or_gt_one(value):
     try:
         ivalue = int(value)
     except ValueError as e:
-        raise argparse.ArgumentTypeError(
-            f"{value} cannot be interpreted as an integer."
-        ) from e
+        raise argparse.ArgumentTypeError(f"{value} cannot be interpreted as an integer.") from e
     if ivalue <= 0:
         raise argparse.ArgumentTypeError(f"{value} is an invalid positive int value.")
     return ivalue
@@ -92,9 +89,7 @@ def main():
     input_pdf = loader.check_pdf(args.input_pdf)
 
     if input_pdf.error_type != "replicas":
-        log.error(
-            "Error type of input PDF must be `replicas` not `%s`", input_pdf.error_type
-        )
+        log.error("Error type of input PDF must be `replicas` not `%s`", input_pdf.error_type)
         sys.exit(1)
 
     if args.replicas > len(input_pdf) - 1:
@@ -115,11 +110,7 @@ def main():
     with tempfile.TemporaryDirectory() as f:
         try:
             new_pdf_from_indexes(
-                input_pdf,
-                indices,
-                set_name=output_name,
-                folder=pathlib.Path(f),
-                installgrid=True,
+                input_pdf, indices, set_name=output_name, folder=pathlib.Path(f), installgrid=True
             )
         except FileExistsError:
             log.error(
@@ -133,39 +124,30 @@ def main():
             "PDFs in the LHAPDF format are required to have 2 replicas, copying "
             "replica 1 to replica 2"
         )
-        base_name = str(
-            pathlib.Path(lhaindex.get_lha_datapath()) / output_name / output_name
-        )
+        base_name = str(pathlib.Path(lhaindex.get_lha_datapath()) / output_name / output_name)
 
-        shutil.copyfile(
-            base_name + "_0001.dat", base_name + "_0002.dat",
-        )
+        shutil.copyfile(base_name + "_0001.dat", base_name + "_0002.dat")
         # fixup info file
-        with open(base_name + ".info", "r") as f:
-            info_file = yaml.safe_load(f)
+        with open(base_name + ".info") as f:
+            info_file = yaml_safe.load(f)
 
         info_file["NumMembers"] = 3
         with open(base_name + ".info", "w") as f:
-            yaml.dump(info_file, f)
+            yaml_safe.dump(info_file, f)
 
         # here we update old indices in case the user creates
         # the original_index_mapping.csv
-        indices = 2*indices
+        indices = 2 * indices
 
     if args.save_indices:
         index_file = (
-            pathlib.Path(lhaindex.get_lha_datapath())
-            / output_name
-            / "original_index_mapping.csv"
+            pathlib.Path(lhaindex.get_lha_datapath()) / output_name / "original_index_mapping.csv"
         )
         log.info("Saving output PDF/input PDF replica index mapping to %s", index_file)
         with open(index_file, "w+") as f:
             pd.DataFrame(
                 list(enumerate(indices, 1)),
-                columns=[
-                    f"{output_name} replica index",
-                    f"{args.input_pdf} replica index",
-                ],
+                columns=[f"{output_name} replica index", f"{args.input_pdf} replica index"],
             ).to_csv(f, index=False)
 
 
diff --git a/validphys2/src/validphys/scripts/vp_pdfrename.py b/validphys2/src/validphys/scripts/vp_pdfrename.py
index 5fd0124cbf..68c9a3748d 100755
--- a/validphys2/src/validphys/scripts/vp_pdfrename.py
+++ b/validphys2/src/validphys/scripts/vp_pdfrename.py
@@ -21,9 +21,8 @@
 import lhapdf
 
 from reportengine import colors
-from reportengine.compat import yaml
-
 from validphys.renametools import rename_pdf
+from validphys.utils import yaml_rt
 
 
 # Taking command line arguments
@@ -45,13 +44,9 @@ def process_args():
                 Quotations should be used for this field.""",
     )
     parser.add_argument(
-        "--data-version",
-        type=int,
-        help="The data version to be added to the PDF .info file.",
-    )
-    parser.add_argument(
-        "--index", help="The set index to be added to the PDF .info file."
+        "--data-version", type=int, help="The data version to be added to the PDF .info file."
     )
+    parser.add_argument("--index", help="The set index to be added to the PDF .info file.")
     parser.add_argument(
         "--reference",
         help="The reference to be added to the PDF .info file, usually an arXiv reference.",
@@ -62,9 +57,7 @@ def process_args():
         action="store_true",
         help="Place the output LHAPDF in the LHAPDF directory.",
     )
-    parser.add_argument(
-        "-c", "--compress", action="store_true", help="Compress the resulting PDF."
-    )
+    parser.add_argument("-c", "--compress", action="store_true", help="Compress the resulting PDF.")
     args = parser.parse_args()
     return args
 
@@ -81,8 +74,7 @@ def fixup_ref(pdf_path: pathlib.Path, field_dict):
     infopath = pdf_path / f"{pdf_name}.info"
 
     with open(infopath) as f:
-        y = yaml.YAML()
-        res = y.load(f)
+        res = yaml_rt.load(f)
 
     # If a field entry is not provided, then we revert to the existing
     # field in pre-existing info file.
@@ -102,12 +94,11 @@ def fixup_ref(pdf_path: pathlib.Path, field_dict):
         res["Reference"] = field_dict["reference"]
 
     with open(infopath, "w") as f:
-        y.default_flow_style = True
-        y.dump(res, f)
+        yaml_rt.dump(res, f)
 
 
 def compress(lhapdf_path: pathlib.Path):
-    """ Function to compress the resulting PDF. Dereferences are handled
+    """Function to compress the resulting PDF. Dereferences are handled
     in order to account for possible symbolic linking of grids.
     """
     output = lhapdf_path.name + ".tar.gz"
@@ -136,9 +127,7 @@ def main():
         sys.exit(1)
 
     if not source_path.is_dir():
-        log.error(
-            f"Could not find fit. Path '{source_path.absolute()}' is not a directory."
-        )
+        log.error(f"Could not find fit. Path '{source_path.absolute()}' is not a directory.")
         sys.exit(1)
 
     with tempfile.TemporaryDirectory(dir=dest_path.parent) as tmp:
@@ -156,6 +145,7 @@ def main():
 
     if args.compress:
         from validphys.renametools import Spinner
+
         log.info("Compressing output")
         with Spinner():
             compress(dest_path)
diff --git a/validphys2/src/validphys/scripts/wiki_upload.py b/validphys2/src/validphys/scripts/wiki_upload.py
index bfc6eb1f12..3be7618b37 100644
--- a/validphys2/src/validphys/scripts/wiki_upload.py
+++ b/validphys2/src/validphys/scripts/wiki_upload.py
@@ -2,17 +2,16 @@
 A more interactive version of vp_upload
 """
 
-#Note that the imports are done as late as possible to improve the speed of
-#the command line.
-
-import sys
-import pathlib
-import os
+# Note that the imports are done as late as possible to improve the speed of
+# the command line.
 
 import logging
+import os
+import pathlib
+import sys
 
-import pygments
 from prompt_toolkit.shortcuts import prompt
+import pygments
 
 from reportengine import colors
 from validphys.promptutils import confirm
@@ -21,14 +20,17 @@
 log.setLevel(logging.INFO)
 log.addHandler(colors.ColorHandler())
 
+
 def handle_single_file(filename):
     import tempfile
+
     out = pathlib.Path(tempfile.mkdtemp(prefix='vp-upload'))
     filename = pathlib.Path(filename)
     p = out / filename.name
     p.symlink_to(filename.absolute())
     return out, filename.name
 
+
 def edit_settings(d):
     title = d.get('title', '')
     author = d.get('author', '')
@@ -48,10 +50,12 @@ def edit_settings(d):
     kwinp = prompt("keywords: ", default=','.join(keywords))
     d['keywords'] = [k.strip() for k in kwinp.split(',') if k]
 
+
 def handle_meta_interactive(output):
     metapath = output / 'meta.yaml'
-    from reportengine.compat import yaml
-    #The yaml lexer is broken. Use something else.
+    from validphys.utils import yaml_safe
+
+    # The yaml lexer is broken. Use something else.
     lex = pygments.lexers.get_lexer_by_name('pkgconfig')
     fmt = pygments.formatters.TerminalFormatter()
     if metapath.exists():
@@ -66,35 +70,37 @@ def handle_meta_interactive(output):
         edit = not confirm(msg, default=True)
 
         if edit:
-            d = yaml.load(content, yaml.RoundTripLoader)
+            d = yaml_safe.load(content)
         else:
             return
 
     else:
-        #We are making these the empty string, because prompt_toolkit doesn't
-        #support default=None.
-        d = {'title': '', 'author': '', 'keywords':''}
+        # We are making these the empty string, because prompt_toolkit doesn't
+        # support default=None.
+        d = {'title': '', 'author': '', 'keywords': ''}
 
     import io
+
     while True:
         edit_settings(d)
 
         print("Metadata:")
 
         s = io.StringIO()
-        yaml.dump(d, s, yaml.RoundTripDumper)
+        yaml_safe.dump(d, s)
         metastr = s.getvalue()
         print(pygments.highlight(metastr, lex, fmt))
 
         if confirm("Confirm?"):
             break
 
-
     with open(metapath, 'w') as f:
         f.write(metastr)
 
+
 def main():
     import argparse
+
     parser = argparse.ArgumentParser(description="Upload output to the NNPDF server.")
     parser.add_argument("output", help="Folder to upload.")
     args = parser.parse_args()
@@ -118,7 +124,6 @@ def main():
         uploader = uploadutils.ReportUploader()
         upargs = output
 
-
     try:
         with uploader.upload_or_exit_context(upargs):
             handle_meta_interactive(upload_output)
diff --git a/validphys2/src/validphys/tests/photon/test_compute.py b/validphys2/src/validphys/tests/photon/test_compute.py
index dd846bdcf2..ff0b64710b 100644
--- a/validphys2/src/validphys/tests/photon/test_compute.py
+++ b/validphys2/src/validphys/tests/photon/test_compute.py
@@ -76,8 +76,7 @@ def test_photon():
 
         # load fiatlux
         with tempfile.NamedTemporaryFile(mode="w") as tmp:
-            with tmp.file as tmp_file:
-                tmp_file.write(yaml.dump(FIATLUX_DEFAULT))
+            yaml.dump(FIATLUX_DEFAULT, tmp)
             lux = fiatlux.FiatLux(tmp.name)
 
         alpha = Alpha(theory, fiatlux_default["q2_max"])
diff --git a/validphys2/src/validphys/tests/test_effexponents.py b/validphys2/src/validphys/tests/test_effexponents.py
index f069402d60..1944e5523c 100644
--- a/validphys2/src/validphys/tests/test_effexponents.py
+++ b/validphys2/src/validphys/tests/test_effexponents.py
@@ -1,10 +1,8 @@
-import pytest
-
-from reportengine.compat import yaml
 from validphys.api import API
 from validphys.loader import FallbackLoader as Loader
 from validphys.scripts.vp_nextfitruncard import PREPROCESSING_LIMS
 from validphys.tests.conftest import FIT, FIT_ITERATED
+from validphys.utils import yaml_safe
 
 
 def test_next_runcard():
@@ -23,10 +21,10 @@ def test_next_runcard():
     # We load it using the context manager because at_input has been modified
     # to load various keys that are not present in the actual runcard for
     # backwards compatibility
-    with open(l.check_fit(FIT_ITERATED).path / "filter.yml", "r") as f:
-        ite2_runcard = yaml.safe_load(f)
+    with open(l.check_fit(FIT_ITERATED).path / "filter.yml") as f:
+        ite2_runcard = yaml_safe.load(f)
 
-    predicted_ite2_runcard = yaml.safe_load(
+    predicted_ite2_runcard = yaml_safe.load(
         API.iterated_runcard_yaml(fit=FIT, _flmap_np_clip_arg=PREPROCESSING_LIMS)
     )
 
diff --git a/validphys2/src/validphys/tests/test_postfit.py b/validphys2/src/validphys/tests/test_postfit.py
index a3f30ac583..31f2ad6cdb 100644
--- a/validphys2/src/validphys/tests/test_postfit.py
+++ b/validphys2/src/validphys/tests/test_postfit.py
@@ -3,14 +3,15 @@
 
 Module for testing postfit.
 """
+
 import json
-import subprocess as sp
 import os
 import shutil
+import subprocess as sp
 
 from validphys.loader import FallbackLoader as Loader
 from validphys.tests.conftest import FIT
-from reportengine.compat import yaml
+from validphys.utils import yaml_safe
 
 
 def test_postfit(tmp):
@@ -76,8 +77,8 @@ def test_postfit(tmp):
         # [File in PDF set, file in fit]
         files = [pdfsetpath / f"{TMPFIT}_{x:04d}.dat", postfitpath / f"replica_{x}/{TMPFIT}.dat"]
         for file in files:
-            with open(file, "r") as f:
-                data = yaml.safe_load_all(f)
+            with open(file) as f:
+                data = yaml_safe.load_all(f)
                 metadata = next(data)
                 repnos.add(metadata["FromMCReplica"])
         assert (
@@ -87,8 +88,8 @@ def test_postfit(tmp):
 
     # Check that number of PDF members is written correctly
     infopath = postfitpath / f"{TMPFIT}/{TMPFIT}.info"
-    with open(infopath, "r") as f:
-        data = yaml.safe_load(f)
+    with open(infopath) as f:
+        data = yaml_safe.load(f)
         # Add one to nrep to account for replica 0
         assert (
             data["NumMembers"] == nrep + 1
@@ -96,7 +97,7 @@ def test_postfit(tmp):
 
     # Check that chi2 and arclength thresholds are recorded correctly
     vetopath = postfitpath / "veto_count.json"
-    with open(vetopath, "r") as f:
+    with open(vetopath) as f:
         veto_count = json.load(f)
         assert (
             veto_count["chi2_threshold"] == chi2_threshold
diff --git a/validphys2/src/validphys/tests/test_scalevariationtheoryids.py b/validphys2/src/validphys/tests/test_scalevariationtheoryids.py
index 71ad3d4183..19ac62c83f 100644
--- a/validphys2/src/validphys/tests/test_scalevariationtheoryids.py
+++ b/validphys2/src/validphys/tests/test_scalevariationtheoryids.py
@@ -2,11 +2,9 @@
 import importlib.resources as resources
 
 import pytest
-from ruamel.yaml import YAML
 
 import validphys.scalevariations
-
-yaml = YAML()
+from validphys.utils import yaml_safe
 
 
 def test_unique_theoryid_variations():
@@ -15,7 +13,7 @@ def test_unique_theoryid_variations():
     """
     file_path = resources.files(validphys.scalevariations).joinpath("scalevariationtheoryids.yaml")
     with file_path.open("r") as file:
-        data = yaml.load(file)
+        data = yaml_safe.load(file)
     thids = [k["theoryid"] for k in data["scale_variations_for"]]
     counter = Counter(thids)
     duplicates = [item for item, count in counter.items() if count > 1]
diff --git a/validphys2/src/validphys/tests/test_theorydbutils.py b/validphys2/src/validphys/tests/test_theorydbutils.py
index a72d86900d..c4349ac272 100644
--- a/validphys2/src/validphys/tests/test_theorydbutils.py
+++ b/validphys2/src/validphys/tests/test_theorydbutils.py
@@ -1,10 +1,10 @@
 import pytest
-from ruamel import yaml
 from validobj import ValidationError
 
 from nnpdf_data.theorydbutils import TheoryNotFoundInDatabase, fetch_all, fetch_theory
 from validphys.api import API
 from validphys.loader import Loader
+from validphys.utils import yaml_safe
 
 L = Loader()
 DBPATH = L.theorydb_folder
@@ -33,7 +33,7 @@ def _dump_and_check_error(tdict, tmp, bad_number=999):
     """Dump theory dict to a file and load expecting an error"""
     tdict["ID"] = bad_number
     ofile = tmp / f"{bad_number}.yaml"
-    yaml.dump(tdict, ofile.open("w"))
+    yaml_safe.dump(tdict, ofile.open("w"))
     with pytest.raises(ValidationError):
         fetch_theory(tmp, bad_number)
 
diff --git a/validphys2/src/validphys/uploadutils.py b/validphys2/src/validphys/uploadutils.py
index 2420845282..f3eb486f69 100644
--- a/validphys2/src/validphys/uploadutils.py
+++ b/validphys2/src/validphys/uploadutils.py
@@ -24,9 +24,9 @@
 from prompt_toolkit.completion import WordCompleter
 
 from reportengine.colors import t
-from reportengine.compat import yaml
 from validphys.loader import Loader, RemoteLoader
 from validphys.renametools import Spinner
+from validphys.utils import yaml_safe
 
 log = logging.getLogger(__name__)
 
@@ -404,7 +404,7 @@ def interactive_meta(path):
 
     meta_dict = {"title": title, "author": author, "keywords": keywords}
     with open(path / "meta.yaml", "w") as stream:
-        yaml.safe_dump(meta_dict, stream)
+        yaml_safe.dump(meta_dict, stream)
 
 
 def check_input(path):
diff --git a/validphys2/src/validphys/utils.py b/validphys2/src/validphys/utils.py
index 1c77fd5b5d..042d8b3925 100644
--- a/validphys2/src/validphys/utils.py
+++ b/validphys2/src/validphys/utils.py
@@ -4,6 +4,11 @@
 import tempfile
 
 import numpy as np
+from ruamel.yaml import YAML
+
+yaml_safe = YAML(typ='safe')
+yaml_rt = YAML(typ='rt')
+yaml_fast = YAML(typ='safe', pure=False)  # uses Cparser if available (not faster than yaml_safe)
 
 
 def generate_path_filtered_data(fit_path, setname):