1 files changed, 12 insertions, 13 deletions
diff --git a/bsie/tools/builder.py b/bsie/tools/builder.py
index 24aea84..190d9bf 100644
--- a/bsie/tools/builder.py
+++ b/bsie/tools/builder.py
@@ -12,7 +12,6 @@ import typing
 # bsie imports
 from bsie import base
 from bsie.base import errors
-from bsie.utils.bsfs import URI, typename
 from bsie.utils import bsfs
 
 # inner-module imports
@@ -75,20 +74,20 @@ class ReaderBuilder():
     """
 
     # keyword arguments
-    kwargs: typing.Dict[str, typing.Dict[str, typing.Any]]
+    _kwargs: typing.Dict[str, typing.Dict[str, typing.Any]]
 
     # cached readers
-    cache: typing.Dict[str, base.reader.Reader]
+    _cache: typing.Dict[str, base.Reader]
 
     def __init__(self, kwargs: typing.Dict[str, typing.Dict[str, typing.Any]]):
-        self.kwargs = kwargs
-        self.cache = {}
+        self._kwargs = kwargs
+        self._cache = {}
 
     def build(self, name: str) -> base.Reader:
         """Return an instance for the qualified class name."""
         # return cached instance
-        if name in self.cache:
-            return self.cache[name]
+        if name in self._cache:
+            return self._cache[name]
 
         # check name and get module/class components
         module_name, class_name = _unpack_name(name)
@@ -97,14 +96,14 @@ class ReaderBuilder():
         cls = _safe_load(module_name, class_name)
 
         # get kwargs
-        kwargs = self.kwargs.get(name, {})
+        kwargs = self._kwargs.get(name, {})
         if not isinstance(kwargs, dict):
             raise TypeError(f'expected a kwargs dict, found {bsfs.typename(kwargs)}')
 
         try: # build, cache, and return instance
             obj = cls(**kwargs)
             # cache instance
-            self.cache[name] = obj
+            self._cache[name] = obj
             # return instance
             return obj
 
@@ -125,19 +124,19 @@ class ExtractorBuilder():
     """
 
     # build specifications
-    specs: typing.List[typing.Dict[str, typing.Dict[str, typing.Any]]]
+    _specs: typing.List[typing.Dict[str, typing.Dict[str, typing.Any]]]
 
     def __init__(self, specs: typing.List[typing.Dict[str, typing.Dict[str, typing.Any]]]):
-        self.specs = specs
+        self._specs = specs
 
     def __iter__(self) -> typing.Iterator[int]:
         """Iterate over extractor specifications."""
-        return iter(range(len(self.specs)))
+        return iter(range(len(self._specs)))
 
     def build(self, index: int) -> base.Extractor:
         """Return an instance of the n'th extractor (n=*index*)."""
         # get build instructions
-        specs = self.specs[index]
+        specs = self._specs[index]
 
         # check specs structure. expecting[{name: {kwargs}}]
         if not isinstance(specs, dict):