diff --git a/maintainers/flake-module.nix b/maintainers/flake-module.nix
index d35b03148..fdac87be3 100644
--- a/maintainers/flake-module.nix
+++ b/maintainers/flake-module.nix
@@ -113,15 +113,15 @@
         ''^src/libfetchers/fetch-to-store\.cc$''
         ''^src/libfetchers/fetchers\.cc$''
         ''^src/libfetchers/fetchers\.hh$''
-        ''^src/libfetchers/filtering-input-accessor\.cc$''
-        ''^src/libfetchers/filtering-input-accessor\.hh$''
-        ''^src/libfetchers/fs-input-accessor\.cc$''
-        ''^src/libfetchers/fs-input-accessor\.hh$''
+        ''^src/libfetchers/filtering-source-accessor\.cc$''
+        ''^src/libfetchers/filtering-source-accessor\.hh$''
+        ''^src/libfetchers/fs-source-accessor\.cc$''
+        ''^src/libfetchers/fs-source-accessor\.hh$''
         ''^src/libfetchers/git-utils\.cc$''
         ''^src/libfetchers/git-utils\.hh$''
         ''^src/libfetchers/github\.cc$''
         ''^src/libfetchers/indirect\.cc$''
-        ''^src/libfetchers/memory-input-accessor\.cc$''
+        ''^src/libfetchers/memory-source-accessor\.cc$''
         ''^src/libfetchers/path\.cc$''
         ''^src/libfetchers/registry\.cc$''
         ''^src/libfetchers/registry\.hh$''
@@ -302,7 +302,7 @@
         ''^src/libutil/hash\.hh$''
         ''^src/libutil/hilite\.cc$''
         ''^src/libutil/hilite\.hh$''
-        ''^src/libutil/input-accessor\.hh$''
+        ''^src/libutil/source-accessor\.hh$''
         ''^src/libutil/json-impls\.hh$''
         ''^src/libutil/json-utils\.cc$''
         ''^src/libutil/json-utils\.hh$''
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 6fd60084d..ad6cdc6d2 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -15,7 +15,7 @@
 #include "function-trace.hh"
 #include "profiles.hh"
 #include "print.hh"
-#include "filtering-input-accessor.hh"
+#include "filtering-source-accessor.hh"
 #include "memory-source-accessor.hh"
 #include "signals.hh"
 #include "gc-small-vector.hh"
@@ -399,7 +399,7 @@ EvalState::EvalState(
     , emptyBindings(0)
     , rootFS(
         evalSettings.restrictEval || evalSettings.pureEval
-        ? ref<SourceAccessor>(AllowListInputAccessor::create(makeFSSourceAccessor(), {},
+        ? ref<SourceAccessor>(AllowListSourceAccessor::create(makeFSSourceAccessor(), {},
             [](const CanonPath & path) -> RestrictedPathError {
                 auto modeInformation = evalSettings.pureEval
                     ? "in pure evaluation mode (use '--impure' to override)"
@@ -460,7 +460,7 @@ EvalState::EvalState(
     }
 
     /* Allow access to all paths in the search path. */
-    if (rootFS.dynamic_pointer_cast<AllowListInputAccessor>())
+    if (rootFS.dynamic_pointer_cast<AllowListSourceAccessor>())
         for (auto & i : lookupPath.elements)
             resolveLookupPathPath(i.path, true);
 
@@ -480,13 +480,13 @@ EvalState::~EvalState()
 
 void EvalState::allowPath(const Path & path)
 {
-    if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListInputAccessor>())
+    if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListSourceAccessor>())
         rootFS2->allowPrefix(CanonPath(path));
 }
 
 void EvalState::allowPath(const StorePath & storePath)
 {
-    if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListInputAccessor>())
+    if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListSourceAccessor>())
         rootFS2->allowPrefix(CanonPath(store->toRealPath(storePath)));
 }
 
@@ -540,13 +540,13 @@ void EvalState::checkURI(const std::string & uri)
     /* If the URI is a path, then check it against allowedPaths as
        well. */
     if (hasPrefix(uri, "/")) {
-        if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListInputAccessor>())
+        if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListSourceAccessor>())
             rootFS2->checkAccess(CanonPath(uri));
         return;
     }
 
     if (hasPrefix(uri, "file://")) {
-        if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListInputAccessor>())
+        if (auto rootFS2 = rootFS.dynamic_pointer_cast<AllowListSourceAccessor>())
             rootFS2->checkAccess(CanonPath(uri.substr(7)));
         return;
     }
diff --git a/src/libexpr/flake/call-flake.nix b/src/libexpr/flake/call-flake.nix
index d0ccb1e37..a411564df 100644
--- a/src/libexpr/flake/call-flake.nix
+++ b/src/libexpr/flake/call-flake.nix
@@ -4,7 +4,7 @@
 lockFileStr:
 
 # A mapping of lock file node IDs to { sourceInfo, subdir } attrsets,
-# with sourceInfo.outPath providing an InputAccessor to a previously
+# with sourceInfo.outPath providing an SourceAccessor to a previously
 # fetched tree. This is necessary for possibly unlocked inputs, in
 # particular the root input, but also --override-inputs pointing to
 # unlocked trees.
diff --git a/src/libfetchers/filtering-input-accessor.cc b/src/libfetchers/filtering-source-accessor.cc
similarity index 61%
rename from src/libfetchers/filtering-input-accessor.cc
rename to src/libfetchers/filtering-source-accessor.cc
index d2b47b5e5..dfd9e536d 100644
--- a/src/libfetchers/filtering-input-accessor.cc
+++ b/src/libfetchers/filtering-source-accessor.cc
@@ -1,25 +1,25 @@
-#include "filtering-input-accessor.hh"
+#include "filtering-source-accessor.hh"
 
 namespace nix {
 
-std::string FilteringInputAccessor::readFile(const CanonPath & path)
+std::string FilteringSourceAccessor::readFile(const CanonPath & path)
 {
     checkAccess(path);
     return next->readFile(prefix / path);
 }
 
-bool FilteringInputAccessor::pathExists(const CanonPath & path)
+bool FilteringSourceAccessor::pathExists(const CanonPath & path)
 {
     return isAllowed(path) && next->pathExists(prefix / path);
 }
 
-std::optional<SourceAccessor::Stat> FilteringInputAccessor::maybeLstat(const CanonPath & path)
+std::optional<SourceAccessor::Stat> FilteringSourceAccessor::maybeLstat(const CanonPath & path)
 {
     checkAccess(path);
     return next->maybeLstat(prefix / path);
 }
 
-SourceAccessor::DirEntries FilteringInputAccessor::readDirectory(const CanonPath & path)
+SourceAccessor::DirEntries FilteringSourceAccessor::readDirectory(const CanonPath & path)
 {
     checkAccess(path);
     DirEntries entries;
@@ -30,18 +30,18 @@ SourceAccessor::DirEntries FilteringInputAccessor::readDirectory(const CanonPath
     return entries;
 }
 
-std::string FilteringInputAccessor::readLink(const CanonPath & path)
+std::string FilteringSourceAccessor::readLink(const CanonPath & path)
 {
     checkAccess(path);
     return next->readLink(prefix / path);
 }
 
-std::string FilteringInputAccessor::showPath(const CanonPath & path)
+std::string FilteringSourceAccessor::showPath(const CanonPath & path)
 {
     return displayPrefix + next->showPath(prefix / path) + displaySuffix;
 }
 
-void FilteringInputAccessor::checkAccess(const CanonPath & path)
+void FilteringSourceAccessor::checkAccess(const CanonPath & path)
 {
     if (!isAllowed(path))
         throw makeNotAllowedError
@@ -49,15 +49,15 @@ void FilteringInputAccessor::checkAccess(const CanonPath & path)
             : RestrictedPathError("access to path '%s' is forbidden", showPath(path));
 }
 
-struct AllowListInputAccessorImpl : AllowListInputAccessor
+struct AllowListSourceAccessorImpl : AllowListSourceAccessor
 {
     std::set<CanonPath> allowedPrefixes;
 
-    AllowListInputAccessorImpl(
+    AllowListSourceAccessorImpl(
         ref<SourceAccessor> next,
         std::set<CanonPath> && allowedPrefixes,
         MakeNotAllowedError && makeNotAllowedError)
-        : AllowListInputAccessor(SourcePath(next), std::move(makeNotAllowedError))
+        : AllowListSourceAccessor(SourcePath(next), std::move(makeNotAllowedError))
         , allowedPrefixes(std::move(allowedPrefixes))
     { }
 
@@ -72,15 +72,15 @@ struct AllowListInputAccessorImpl : AllowListInputAccessor
     }
 };
 
-ref<AllowListInputAccessor> AllowListInputAccessor::create(
+ref<AllowListSourceAccessor> AllowListSourceAccessor::create(
     ref<SourceAccessor> next,
     std::set<CanonPath> && allowedPrefixes,
     MakeNotAllowedError && makeNotAllowedError)
 {
-    return make_ref<AllowListInputAccessorImpl>(next, std::move(allowedPrefixes), std::move(makeNotAllowedError));
+    return make_ref<AllowListSourceAccessorImpl>(next, std::move(allowedPrefixes), std::move(makeNotAllowedError));
 }
 
-bool CachingFilteringInputAccessor::isAllowed(const CanonPath & path)
+bool CachingFilteringSourceAccessor::isAllowed(const CanonPath & path)
 {
     auto i = cache.find(path);
     if (i != cache.end()) return i->second;
diff --git a/src/libfetchers/filtering-input-accessor.hh b/src/libfetchers/filtering-source-accessor.hh
similarity index 73%
rename from src/libfetchers/filtering-input-accessor.hh
rename to src/libfetchers/filtering-source-accessor.hh
index ddf18eea4..9ec7bc21f 100644
--- a/src/libfetchers/filtering-input-accessor.hh
+++ b/src/libfetchers/filtering-source-accessor.hh
@@ -12,17 +12,17 @@ namespace nix {
 typedef std::function<RestrictedPathError(const CanonPath & path)> MakeNotAllowedError;
 
 /**
- * An abstract wrapping `InputAccessor` that performs access
+ * An abstract wrapping `SourceAccessor` that performs access
  * control. Subclasses should override `isAllowed()` to implement an
  * access control policy. The error message is customized at construction.
  */
-struct FilteringInputAccessor : SourceAccessor
+struct FilteringSourceAccessor : SourceAccessor
 {
     ref<SourceAccessor> next;
     CanonPath prefix;
     MakeNotAllowedError makeNotAllowedError;
 
-    FilteringInputAccessor(const SourcePath & src, MakeNotAllowedError && makeNotAllowedError)
+    FilteringSourceAccessor(const SourcePath & src, MakeNotAllowedError && makeNotAllowedError)
         : next(src.accessor)
         , prefix(src.path)
         , makeNotAllowedError(std::move(makeNotAllowedError))
@@ -55,32 +55,32 @@ struct FilteringInputAccessor : SourceAccessor
 };
 
 /**
- * A wrapping `InputAccessor` that checks paths against a set of
+ * A wrapping `SourceAccessor` that checks paths against a set of
  * allowed prefixes.
  */
-struct AllowListInputAccessor : public FilteringInputAccessor
+struct AllowListSourceAccessor : public FilteringSourceAccessor
 {
     /**
      * Grant access to the specified prefix.
      */
     virtual void allowPrefix(CanonPath prefix) = 0;
 
-    static ref<AllowListInputAccessor> create(
+    static ref<AllowListSourceAccessor> create(
         ref<SourceAccessor> next,
         std::set<CanonPath> && allowedPrefixes,
         MakeNotAllowedError && makeNotAllowedError);
 
-    using FilteringInputAccessor::FilteringInputAccessor;
+    using FilteringSourceAccessor::FilteringSourceAccessor;
 };
 
 /**
- * A wrapping `InputAccessor` mix-in where `isAllowed()` caches the result of virtual `isAllowedUncached()`.
+ * A wrapping `SourceAccessor` mix-in where `isAllowed()` caches the result of virtual `isAllowedUncached()`.
  */
-struct CachingFilteringInputAccessor : FilteringInputAccessor
+struct CachingFilteringSourceAccessor : FilteringSourceAccessor
 {
     std::map<CanonPath, bool> cache;
 
-    using FilteringInputAccessor::FilteringInputAccessor;
+    using FilteringSourceAccessor::FilteringSourceAccessor;
 
     bool isAllowed(const CanonPath & path) override;
 
diff --git a/src/libfetchers/git-utils.cc b/src/libfetchers/git-utils.cc
index a91587cb4..160d1ac05 100644
--- a/src/libfetchers/git-utils.cc
+++ b/src/libfetchers/git-utils.cc
@@ -53,7 +53,7 @@ bool operator == (const git_oid & oid1, const git_oid & oid2)
 
 namespace nix {
 
-struct GitInputAccessor;
+struct GitSourceAccessor;
 
 // Some wrapper types that ensure that the git_*_free functions get called.
 template<auto del>
@@ -330,9 +330,9 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
     }
 
     /**
-     * A 'GitInputAccessor' with no regard for export-ignore or any other transformations.
+     * A 'GitSourceAccessor' with no regard for export-ignore or any other transformations.
      */
-    ref<GitInputAccessor> getRawAccessor(const Hash & rev);
+    ref<GitSourceAccessor> getRawAccessor(const Hash & rev);
 
     ref<SourceAccessor> getAccessor(const Hash & rev, bool exportIgnore) override;
 
@@ -473,12 +473,12 @@ ref<GitRepo> GitRepo::openRepo(const std::filesystem::path & path, bool create,
 /**
  * Raw git tree input accessor.
  */
-struct GitInputAccessor : SourceAccessor
+struct GitSourceAccessor : SourceAccessor
 {
     ref<GitRepoImpl> repo;
     Tree root;
 
-    GitInputAccessor(ref<GitRepoImpl> repo_, const Hash & rev)
+    GitSourceAccessor(ref<GitRepoImpl> repo_, const Hash & rev)
         : repo(repo_)
         , root(peelObject<Tree>(*repo, lookupObject(*repo, hashToOID(rev)).get(), GIT_OBJECT_TREE))
     {
@@ -702,12 +702,12 @@ struct GitInputAccessor : SourceAccessor
     }
 };
 
-struct GitExportIgnoreInputAccessor : CachingFilteringInputAccessor {
+struct GitExportIgnoreSourceAccessor : CachingFilteringSourceAccessor {
     ref<GitRepoImpl> repo;
     std::optional<Hash> rev;
 
-    GitExportIgnoreInputAccessor(ref<GitRepoImpl> repo, ref<SourceAccessor> next, std::optional<Hash> rev)
-        : CachingFilteringInputAccessor(next, [&](const CanonPath & path) {
+    GitExportIgnoreSourceAccessor(ref<GitRepoImpl> repo, ref<SourceAccessor> next, std::optional<Hash> rev)
+        : CachingFilteringSourceAccessor(next, [&](const CanonPath & path) {
             return RestrictedPathError(fmt("'%s' does not exist because it was fetched with exportIgnore enabled", path));
         })
         , repo(repo)
@@ -918,18 +918,18 @@ struct GitFileSystemObjectSinkImpl : GitFileSystemObjectSink
     }
 };
 
-ref<GitInputAccessor> GitRepoImpl::getRawAccessor(const Hash & rev)
+ref<GitSourceAccessor> GitRepoImpl::getRawAccessor(const Hash & rev)
 {
     auto self = ref<GitRepoImpl>(shared_from_this());
-    return make_ref<GitInputAccessor>(self, rev);
+    return make_ref<GitSourceAccessor>(self, rev);
 }
 
 ref<SourceAccessor> GitRepoImpl::getAccessor(const Hash & rev, bool exportIgnore)
 {
     auto self = ref<GitRepoImpl>(shared_from_this());
-    ref<GitInputAccessor> rawGitAccessor = getRawAccessor(rev);
+    ref<GitSourceAccessor> rawGitAccessor = getRawAccessor(rev);
     if (exportIgnore) {
-        return make_ref<GitExportIgnoreInputAccessor>(self, rawGitAccessor, rev);
+        return make_ref<GitExportIgnoreSourceAccessor>(self, rawGitAccessor, rev);
     }
     else {
         return rawGitAccessor;
@@ -940,18 +940,18 @@ ref<SourceAccessor> GitRepoImpl::getAccessor(const WorkdirInfo & wd, bool export
 {
     auto self = ref<GitRepoImpl>(shared_from_this());
     /* In case of an empty workdir, return an empty in-memory tree. We
-       cannot use AllowListInputAccessor because it would return an
+       cannot use AllowListSourceAccessor because it would return an
        error for the root (and we can't add the root to the allow-list
        since that would allow access to all its children). */
     ref<SourceAccessor> fileAccessor =
         wd.files.empty()
         ? makeEmptySourceAccessor()
-        : AllowListInputAccessor::create(
+        : AllowListSourceAccessor::create(
             makeFSSourceAccessor(path),
             std::set<CanonPath> { wd.files },
             std::move(makeNotAllowedError)).cast<SourceAccessor>();
     if (exportIgnore)
-        return make_ref<GitExportIgnoreInputAccessor>(self, fileAccessor, std::nullopt);
+        return make_ref<GitExportIgnoreSourceAccessor>(self, fileAccessor, std::nullopt);
     else
         return fileAccessor;
 }
diff --git a/src/libfetchers/git-utils.hh b/src/libfetchers/git-utils.hh
index e264b2f63..29d799554 100644
--- a/src/libfetchers/git-utils.hh
+++ b/src/libfetchers/git-utils.hh
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "filtering-input-accessor.hh"
+#include "filtering-source-accessor.hh"
 #include "fs-sink.hh"
 
 namespace nix {
diff --git a/src/libfetchers/mounted-input-accessor.hh b/src/libfetchers/mounted-input-accessor.hh
deleted file mode 100644
index 74e040f44..000000000
--- a/src/libfetchers/mounted-input-accessor.hh
+++ /dev/null
@@ -1,9 +0,0 @@
-#pragma once
-
-#include "source-accessor.hh"
-
-namespace nix {
-
-ref<SourceAccessor> makeMountedInputAccessor(std::map<CanonPath, ref<SourceAccessor>> mounts);
-
-}
diff --git a/src/libfetchers/mounted-input-accessor.cc b/src/libfetchers/mounted-source-accessor.cc
similarity index 86%
rename from src/libfetchers/mounted-input-accessor.cc
rename to src/libfetchers/mounted-source-accessor.cc
index 4d086c7ad..68f3a546b 100644
--- a/src/libfetchers/mounted-input-accessor.cc
+++ b/src/libfetchers/mounted-source-accessor.cc
@@ -1,12 +1,12 @@
-#include "mounted-input-accessor.hh"
+#include "mounted-source-accessor.hh"
 
 namespace nix {
 
-struct MountedInputAccessor : SourceAccessor
+struct MountedSourceAccessor : SourceAccessor
 {
     std::map<CanonPath, ref<SourceAccessor>> mounts;
 
-    MountedInputAccessor(std::map<CanonPath, ref<SourceAccessor>> _mounts)
+    MountedSourceAccessor(std::map<CanonPath, ref<SourceAccessor>> _mounts)
         : mounts(std::move(_mounts))
     {
         displayPrefix.clear();
@@ -71,9 +71,9 @@ struct MountedInputAccessor : SourceAccessor
     }
 };
 
-ref<SourceAccessor> makeMountedInputAccessor(std::map<CanonPath, ref<SourceAccessor>> mounts)
+ref<SourceAccessor> makeMountedSourceAccessor(std::map<CanonPath, ref<SourceAccessor>> mounts)
 {
-    return make_ref<MountedInputAccessor>(std::move(mounts));
+    return make_ref<MountedSourceAccessor>(std::move(mounts));
 }
 
 }
diff --git a/src/libfetchers/mounted-source-accessor.hh b/src/libfetchers/mounted-source-accessor.hh
new file mode 100644
index 000000000..45cbcb09a
--- /dev/null
+++ b/src/libfetchers/mounted-source-accessor.hh
@@ -0,0 +1,9 @@
+#pragma once
+
+#include "source-accessor.hh"
+
+namespace nix {
+
+ref<SourceAccessor> makeMountedSourceAccessor(std::map<CanonPath, ref<SourceAccessor>> mounts);
+
+}
diff --git a/src/libfetchers/unix/git.cc b/src/libfetchers/unix/git.cc
index c8fd295c0..46263c872 100644
--- a/src/libfetchers/unix/git.cc
+++ b/src/libfetchers/unix/git.cc
@@ -9,7 +9,7 @@
 #include "pathlocks.hh"
 #include "processes.hh"
 #include "git.hh"
-#include "mounted-input-accessor.hh"
+#include "mounted-source-accessor.hh"
 #include "git-utils.hh"
 #include "logging.hh"
 #include "finally.hh"
@@ -652,7 +652,7 @@ struct GitInputScheme : InputScheme
 
             if (!mounts.empty()) {
                 mounts.insert_or_assign(CanonPath::root, accessor);
-                accessor = makeMountedInputAccessor(std::move(mounts));
+                accessor = makeMountedSourceAccessor(std::move(mounts));
             }
         }
 
@@ -715,7 +715,7 @@ struct GitInputScheme : InputScheme
             }
 
             mounts.insert_or_assign(CanonPath::root, accessor);
-            accessor = makeMountedInputAccessor(std::move(mounts));
+            accessor = makeMountedSourceAccessor(std::move(mounts));
         }
 
         if (!repoInfo.workdirInfo.isDirty) {
diff --git a/src/libutil/source-accessor.hh b/src/libutil/source-accessor.hh
index 548feddfd..b3fb9fe08 100644
--- a/src/libutil/source-accessor.hh
+++ b/src/libutil/source-accessor.hh
@@ -190,7 +190,7 @@ ref<SourceAccessor> makeEmptySourceAccessor();
 
 /**
  * Exception thrown when accessing a filtered path (see
- * `FilteringInputAccessor`).
+ * `FilteringSourceAccessor`).
  */
 MakeError(RestrictedPathError, Error);