diff --git a/fast_plotter/v1/__init__.py b/fast_plotter/v1/__init__.py
new file mode 100644
index 0000000..0939319
--- /dev/null
+++ b/fast_plotter/v1/__init__.py
@@ -0,0 +1,65 @@
+""" Features for version 1 """
+from typing import Any, Dict, List
+import uproot
+
+from .hist_collections import EfficiencyHistCollection
+
+
+def create_collection(name, config, style):
+    LOOKUP = {
+        "efficiency": EfficiencyHistCollection,
+    }
+    collection_class = LOOKUP[config["type"]]
+#     return collection_class(**config)
+    return collection_class(
+        name=name,
+        title=config["title"],
+        style=style,
+    )
+
+
+def _workaround_uproot_issue38():
+    # workaround for issue reading TEfficiency
+    # https://github.com/scikit-hep/uproot5/issues/38
+    import skhep_testdata
+    with uproot.open(skhep_testdata.data_path("uproot-issue38c.root")) as fp:
+        hist = fp["TEfficiencyName"]
+    # now all TEfficiency objects should be readable
+    return hist
+
+
+def read_histogram_file(input_file, histname):
+    with uproot.open(input_file) as fp:
+        hist = fp[histname]
+        # TODO: use filter_dict to get > 1 hist
+    return hist
+
+
+def make_plots(plot_config: Dict[str, Any], input_files: List[str], output_dir: str):
+    _workaround_uproot_issue38()
+    input_file = input_files[0]
+
+    plotter_version = plot_config.pop("plotter-version", "0")
+    styles = plot_config.pop("styles", {})
+    collections = plot_config.pop("collections", {})
+    named_styles = {}
+    for style in styles:
+        named_styles[style["name"]] = style
+
+    for name, config in collections.items():
+        # TODO: needs to me safer
+        style = named_styles[config.pop("style")]
+        collection = create_collection(name, config, style)
+        sources = config.pop("sources")
+        for source in sources:
+            label = source.pop("label")
+            path = source.pop("path")
+            hist = read_histogram_file(input_file, path)
+            collection.add_hist(
+                name=label,
+                numerator=hist.members["fPassedHistogram"].to_numpy()[0],
+                denominator=hist.members["fTotalHistogram"].to_numpy()[0],
+            )
+
+        collection.plot()
+        collection.save(output_dir)
diff --git a/fast_plotter/v1/hist_collections.py b/fast_plotter/v1/hist_collections.py
new file mode 100644
index 0000000..cd1ccad
--- /dev/null
+++ b/fast_plotter/v1/hist_collections.py
@@ -0,0 +1,71 @@
+import os
+import numpy as np
+
+from hist.intervals import ratio_uncertainty
+import mplhep as hep
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.pyplot as plt
+
+
+class EfficiencyHistCollection():
+
+    def __init__(self, name, title, style):
+        self.name = name
+        self.title = title
+        self.style = style
+        self.hists = []
+
+    def add_hist(self, name, numerator, denominator, **kwargs):
+        self.hists.append(Efficiency(name, numerator, denominator, **kwargs))
+
+    def plot(self, **kwargs):
+        hep.style.use("CMS")
+        fig = plt.figure(figsize=(10, 8))
+        for hist in self.hists:
+            hep.histplot(hist.eff, yerr=hist.eff_err, **kwargs)
+    
+    def save(self, output_dir):
+        output_file = os.path.join(output_dir, f"{self.name}.png")
+        print(f"Saving {output_file}")
+        plt.savefig(output_file)
+
+
+class Efficiency:
+    num: np.ndarray
+    den: np.ndarray
+    name: str
+
+    def __init__(self, name, num, den):
+        self.name = name
+        self.num = num
+        self.den = den
+        self._eff = None
+        self._eff_err = None
+
+    @property
+    def eff(self):
+        if self._eff is None:
+            old_settings = np.seterr()
+            np.seterr(divide='ignore', invalid='ignore')
+            self._eff = np.divide(self.num, self.den, dtype=np.float64)
+            np.seterr(**old_settings)
+            self._eff[np.isnan(self._eff)] = 0.0
+
+        return self._eff
+
+    @property
+    def eff_err(self):
+        if self._eff_err is None:
+            if np.any(self.num > self.den):
+                raise ValueError(
+                    "Found numerator larger than denominator while calculating binomial uncertainty"
+                )
+            self._eff_err = ratio_uncertainty(self.num, self.den, uncertainty_type="efficiency")
+        return self._eff_err
+
+    def plot(self, **kwargs):
+        hep.histplot(self.eff, yerr=self.eff_err, **kwargs)
+
+    def __repr__(self):
+        return f"EfficiencyHist(num={self.num}, den={self.den})"
diff --git a/fast_plotter/version.py b/fast_plotter/version.py
index b8fe69f..6c7023a 100644
--- a/fast_plotter/version.py
+++ b/fast_plotter/version.py
@@ -12,5 +12,5 @@ def split_version(version):
     return tuple(result)
 
 
-__version__ = '0.10.4'
+__version__ = '1.0.0a0'
 version_info = split_version(__version__) # noqa
diff --git a/setup.cfg b/setup.cfg
index dbde0d2..a972315 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.10.4
+current_version = 1.0.0a0
 commit = True
 tag = False
 
diff --git a/setup.py b/setup.py
index d19ac0d..eee0eb9 100644
--- a/setup.py
+++ b/setup.py
@@ -37,11 +37,12 @@ def get_version():
         'Intended Audience :: Science/Research',
         'License :: OSI Approved :: Apache Software License',
         'Natural Language :: English',
-        'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
-        'Programming Language :: Python :: 3.6',
-        'Programming Language :: Python :: 3.7',
-        'Programming Language :: Python :: 3.8',
+        "Programming Language :: Python",
+        "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: 3 :: Only",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
     ],
     description="F.A.S.T. plotter package",
     entry_points={