diff --git a/scripts/bulk-process.py b/scripts/bulk-process.py
index f22c55e0..ef51a4aa 100644
--- a/scripts/bulk-process.py
+++ b/scripts/bulk-process.py
@@ -81,6 +81,7 @@ def get_capa_results(args):
       rules (capa.rules.RuleSet): the rules to match
       signatures (List[str]): list of file system paths to signature files
       format (str): the name of the sample file format
+      os (str): the name of the operating system
       path (str): the file system path to the sample to process
 
     args is a tuple because i'm not quite sure how to unpack multiple arguments using `map`.
@@ -96,12 +97,12 @@ def get_capa_results(args):
       meta (dict): the meta analysis results
       capabilities (dict): the matched capabilities and their result objects
     """
-    rules, sigpaths, format, path = args
+    rules, sigpaths, format, os, path = args
     should_save_workspace = os.environ.get("CAPA_SAVE_WORKSPACE") not in ("0", "no", "NO", "n", None)
     logger.info("computing capa results for: %s", path)
     try:
         extractor = capa.main.get_extractor(
-            path, format, capa.main.BACKEND_VIV, sigpaths, should_save_workspace, disable_progress=True
+            path, format, os, capa.main.BACKEND_VIV, sigpaths, should_save_workspace, disable_progress=True
         )
     except capa.main.UnsupportedFormatError:
         # i'm 100% sure if multiprocessing will reliably raise exceptions across process boundaries.
@@ -127,7 +128,7 @@ def get_capa_results(args):
             "error": f"unexpected error: {e}",
         }
 
-    meta = capa.main.collect_metadata([], path, [], extractor)
+    meta = capa.main.collect_metadata([], path, format, os, [], extractor)
     capabilities, counts = capa.main.find_capabilities(rules, extractor, disable_progress=True)
     meta["analysis"].update(counts)
     meta["analysis"]["layout"] = capa.main.compute_layout(rules, extractor, capabilities)
@@ -142,7 +143,7 @@ def main(argv=None):
         argv = sys.argv[1:]
 
         parser = argparse.ArgumentParser(description="detect capabilities in programs.")
-        capa.main.install_common_args(parser, wanted={"rules", "signatures"})
+        capa.main.install_common_args(parser, wanted={"rules", "signatures", "format", "os"})
         parser.add_argument("input", type=str, help="Path to directory of files to recursively analyze")
         parser.add_argument(
             "-n", "--parallelism", type=int, default=multiprocessing.cpu_count(), help="parallelism factor"
diff --git a/scripts/capa_as_library.py b/scripts/capa_as_library.py
index 884b2e94..5d97d2b6 100644
--- a/scripts/capa_as_library.py
+++ b/scripts/capa_as_library.py
@@ -14,6 +14,7 @@ import capa.render.default
 import capa.render.result_document as rd
 import capa.features.freeze.features as frzf
 from capa.engine import *
+from capa.features.common import OS_AUTO
 
 
 # == Render dictionary helpers
@@ -164,11 +165,13 @@ def capa_details(rules_path, file_path, output_format="dictionary"):
     rules = capa.main.get_rules([rules_path])
 
     # extract features and find capabilities
-    extractor = capa.main.get_extractor(file_path, "auto", capa.main.BACKEND_VIV, [], False, disable_progress=True)
+    extractor = capa.main.get_extractor(
+        file_path, "auto", OS_AUTO, capa.main.BACKEND_VIV, [], False, disable_progress=True
+    )
     capabilities, counts = capa.main.find_capabilities(rules, extractor, disable_progress=True)
 
     # collect metadata (used only to make rendering more complete)
-    meta = capa.main.collect_metadata([], file_path, rules_path, extractor)
+    meta = capa.main.collect_metadata([], file_path, "auto", OS_AUTO, rules_path, extractor)
     meta["analysis"].update(counts)
     meta["analysis"]["layout"] = capa.main.compute_layout(rules, extractor, capabilities)
 
diff --git a/scripts/lint.py b/scripts/lint.py
index cf56f1a8..92c7fbcf 100644
--- a/scripts/lint.py
+++ b/scripts/lint.py
@@ -45,7 +45,7 @@ import capa.engine
 import capa.helpers
 import capa.features.insn
 from capa.rules import Rule, RuleSet
-from capa.features.common import FORMAT_PE, FORMAT_DOTNET, String, Feature, Substring
+from capa.features.common import OS_AUTO, FORMAT_PE, FORMAT_DOTNET, String, Feature, Substring
 from capa.render.result_document import RuleMetadata
 
 logger = logging.getLogger("lint")
@@ -310,7 +310,9 @@ def get_sample_capabilities(ctx: Context, path: Path) -> Set[str]:
         format_ = capa.main.get_auto_format(nice_path)
 
     logger.debug("analyzing sample: %s", nice_path)
-    extractor = capa.main.get_extractor(nice_path, format_, "", DEFAULT_SIGNATURES, False, disable_progress=True)
+    extractor = capa.main.get_extractor(
+        nice_path, format_, OS_AUTO, "", DEFAULT_SIGNATURES, False, disable_progress=True
+    )
 
     capabilities, _ = capa.main.find_capabilities(ctx.rules, extractor, disable_progress=True)
     # mypy doesn't seem to be happy with the MatchResults type alias & set(...keys())?
diff --git a/scripts/profile-time.py b/scripts/profile-time.py
index 0c7f0783..9b97b767 100644
--- a/scripts/profile-time.py
+++ b/scripts/profile-time.py
@@ -71,7 +71,7 @@ def main(argv=None):
         label += " (dirty)"
 
     parser = argparse.ArgumentParser(description="Profile capa performance")
-    capa.main.install_common_args(parser, wanted={"format", "sample", "signatures", "rules"})
+    capa.main.install_common_args(parser, wanted={"format", "os", "sample", "signatures", "rules"})
 
     parser.add_argument("--number", type=int, default=3, help="batch size of profile collection")
     parser.add_argument("--repeat", type=int, default=30, help="batch count of profile collection")
@@ -104,7 +104,7 @@ def main(argv=None):
             extractor = capa.features.freeze.load(f.read())
     else:
         extractor = capa.main.get_extractor(
-            args.sample, args.format, capa.main.BACKEND_VIV, sig_paths, should_save_workspace=False
+            args.sample, args.format, args.os, capa.main.BACKEND_VIV, sig_paths, should_save_workspace=False
         )
 
     with tqdm.tqdm(total=args.number * args.repeat) as pbar:
diff --git a/scripts/show-capabilities-by-function.py b/scripts/show-capabilities-by-function.py
index dbd47f8f..a7dea657 100644
--- a/scripts/show-capabilities-by-function.py
+++ b/scripts/show-capabilities-by-function.py
@@ -130,7 +130,7 @@ def main(argv=None):
         argv = sys.argv[1:]
 
     parser = argparse.ArgumentParser(description="detect capabilities in programs.")
-    capa.main.install_common_args(parser, wanted={"format", "backend", "sample", "signatures", "rules", "tag"})
+    capa.main.install_common_args(parser, wanted={"format", "os", "backend", "sample", "signatures", "rules", "tag"})
     args = parser.parse_args(args=argv)
     capa.main.handle_common_args(args)
 
@@ -166,7 +166,7 @@ def main(argv=None):
 
         try:
             extractor = capa.main.get_extractor(
-                args.sample, args.format, args.backend, sig_paths, should_save_workspace
+                args.sample, args.format, args.os, args.backend, sig_paths, should_save_workspace
             )
         except capa.exceptions.UnsupportedFormatError:
             capa.helpers.log_unsupported_format_error()
@@ -175,7 +175,7 @@ def main(argv=None):
             capa.helpers.log_unsupported_runtime_error()
             return -1
 
-    meta = capa.main.collect_metadata(argv, args.sample, args.rules, extractor)
+    meta = capa.main.collect_metadata(argv, args.sample, format_, args.os, args.rules, extractor)
     capabilities, counts = capa.main.find_capabilities(rules, extractor)
     meta["analysis"].update(counts)
     meta["analysis"]["layout"] = capa.main.compute_layout(rules, extractor, capabilities)
diff --git a/scripts/show-features.py b/scripts/show-features.py
index 297977d5..365a6d70 100644
--- a/scripts/show-features.py
+++ b/scripts/show-features.py
@@ -95,7 +95,7 @@ def main(argv=None):
         argv = sys.argv[1:]
 
     parser = argparse.ArgumentParser(description="Show the features that capa extracts from the given sample")
-    capa.main.install_common_args(parser, wanted={"format", "sample", "signatures", "backend"})
+    capa.main.install_common_args(parser, wanted={"format", "os", "sample", "signatures", "backend"})
 
     parser.add_argument("-F", "--function", type=str, help="Show features for specific function")
     args = parser.parse_args(args=argv)
@@ -120,7 +120,7 @@ def main(argv=None):
         should_save_workspace = os.environ.get("CAPA_SAVE_WORKSPACE") not in ("0", "no", "NO", "n", None)
         try:
             extractor = capa.main.get_extractor(
-                args.sample, args.format, args.backend, sig_paths, should_save_workspace
+                args.sample, args.format, args.os, args.backend, sig_paths, should_save_workspace
             )
         except capa.exceptions.UnsupportedFormatError:
             capa.helpers.log_unsupported_format_error()
diff --git a/tests/fixtures.py b/tests/fixtures.py
index 5602f096..5fb31539 100644
--- a/tests/fixtures.py
+++ b/tests/fixtures.py
@@ -26,6 +26,7 @@ import capa.features.basicblock
 from capa.features.common import (
     OS,
     OS_ANY,
+    OS_AUTO,
     OS_LINUX,
     ARCH_I386,
     FORMAT_PE,
@@ -106,7 +107,7 @@ def get_viv_extractor(path):
     else:
         vw = capa.main.get_workspace(path, "auto", sigpaths=sigpaths)
     vw.saveWorkspace()
-    extractor = capa.features.extractors.viv.extractor.VivisectFeatureExtractor(vw, path)
+    extractor = capa.features.extractors.viv.extractor.VivisectFeatureExtractor(vw, path, OS_AUTO)
     fixup_viv(path, extractor)
     return extractor