diff --git a/swh/loader/package/debian/loader.py b/swh/loader/package/debian/loader.py
--- a/swh/loader/package/debian/loader.py
+++ b/swh/loader/package/debian/loader.py
@@ -248,23 +248,6 @@
         )
 
 
-def _artifact_to_dsc_sha256(known_artifacts: Dict, url: str) -> Optional[str]:
-    extrinsic = known_artifacts.get("extrinsic")
-    if not extrinsic:
-        return None
-
-    known_p_info = DebianPackageInfo.from_metadata(extrinsic["raw"], url=url)
-    dsc = [file for (name, file) in known_p_info.files.items() if name.endswith(".dsc")]
-
-    if len(dsc) != 1:
-        raise DscCountError(
-            f"Expected exactly one known .dsc file for package {known_p_info.name}, "
-            f"got {len(dsc)}"
-        )
-
-    return dsc[0].sha256
-
-
 def uid_to_person(uid: str) -> Dict[str, str]:
     """Convert an uid to a person suitable for insertion.
 
diff --git a/swh/loader/package/loader.py b/swh/loader/package/loader.py
--- a/swh/loader/package/loader.py
+++ b/swh/loader/package/loader.py
@@ -36,7 +36,6 @@
 from swh.loader.exception import NotFound
 from swh.loader.package.utils import download
 from swh.model import from_disk
-from swh.model.collections import ImmutableDict
 from swh.model.hashutil import hash_to_hex
 from swh.model.model import (
     ExtID,
@@ -50,7 +49,6 @@
     Revision,
     Sha1Git,
     Snapshot,
-    TargetType,
 )
 from swh.model.swhids import CoreSWHID, ExtendedObjectType, ExtendedSWHID, ObjectType
 from swh.storage.algos.snapshot import snapshot_get_latest
@@ -219,32 +217,6 @@
         """
         return snapshot_get_latest(self.storage, self.url)
 
-    def known_artifacts(
-        self, snapshot: Optional[Snapshot]
-    ) -> Dict[Sha1Git, Optional[ImmutableDict[str, object]]]:
-        """Retrieve the known releases/artifact for the origin.
-
-        Args
-            snapshot: snapshot for the visit
-
-        Returns:
-            Dict of keys revision id (bytes), values a metadata Dict.
-
-        """
-        if not snapshot:
-            return {}
-
-        # retrieve only revisions (e.g the alias we do not want here)
-        revs = [
-            rev.target
-            for rev in snapshot.branches.values()
-            if rev and rev.target_type == TargetType.REVISION
-        ]
-        known_revisions = self.storage.revision_get(revs)
-        return {
-            revision.id: revision.metadata for revision in known_revisions if revision
-        }
-
     def new_packageinfo_to_extid(self, p_info: TPackageInfo) -> Optional[PartialExtID]:
         return p_info.extid()
 
@@ -514,8 +486,6 @@
         try:
             last_snapshot = self.last_snapshot()
             logger.debug("last snapshot: %s", last_snapshot)
-            known_artifacts = self.known_artifacts(last_snapshot)
-            logger.debug("known artifacts: %s", known_artifacts)
         except Exception as e:
             logger.exception("Failed to get previous state for %s", self.url)
             sentry_sdk.capture_exception(e)
diff --git a/swh/loader/package/nixguix/loader.py b/swh/loader/package/nixguix/loader.py
--- a/swh/loader/package/nixguix/loader.py
+++ b/swh/loader/package/nixguix/loader.py
@@ -19,15 +19,12 @@
 )
 from swh.loader.package.utils import EMPTY_AUTHOR, api_info, cached_method
 from swh.model import hashutil
-from swh.model.collections import ImmutableDict
 from swh.model.model import (
     MetadataAuthority,
     MetadataAuthorityType,
     Revision,
     RevisionType,
     Sha1Git,
-    Snapshot,
-    TargetType,
 )
 from swh.storage.interface import StorageInterface
 
@@ -126,35 +123,6 @@
         p_info = NixGuixPackageInfo.from_metadata({"url": url, "integrity": integrity})
         yield url, p_info
 
-    def known_artifacts(
-        self, snapshot: Optional[Snapshot]
-    ) -> Dict[Sha1Git, Optional[ImmutableDict[str, object]]]:
-        """Almost same implementation as the default one except it filters out the extra
-        "evaluation" branch which does not have the right metadata structure.
-
-        """
-        if not snapshot:
-            return {}
-
-        # Skip evaluation revision which has no metadata
-        revs = [
-            rev.target
-            for branch_name, rev in snapshot.branches.items()
-            if (
-                rev
-                and rev.target_type == TargetType.REVISION
-                and branch_name != b"evaluation"
-            )
-        ]
-        known_revisions = self.storage.revision_get(revs)
-
-        ret = {}
-        for revision in known_revisions:
-            if not revision:  # revision_get can return None
-                continue
-            ret[revision.id] = revision.metadata
-        return ret
-
     def extra_branches(self) -> Dict[bytes, Mapping[str, Any]]:
         """We add a branch to the snapshot called 'evaluation' pointing to the
         revision used to generate the sources.json file. This revision