SERVER-45838 Rename/restructure mongo_process_interface classes and files

 create mode 100644 src/mongo/db/pipeline/process_interface/SConscript
 rename src/mongo/db/pipeline/{process_interface_standalone.cpp => process_interface/common_mongod_process_interface.cpp} (72%)
 rename src/mongo/db/pipeline/{process_interface_standalone.h => process_interface/common_mongod_process_interface.h} (69%)
 rename src/mongo/db/pipeline/{mongo_process_common.cpp => process_interface/common_process_interface.cpp} (91%)
 rename src/mongo/db/pipeline/{mongo_process_common.h => process_interface/common_process_interface.h} (91%)
 rename src/mongo/db/pipeline/{ => process_interface}/mongo_process_interface.cpp (96%)
 rename src/mongo/db/pipeline/{ => process_interface}/mongo_process_interface.h (100%)
 rename src/mongo/db/pipeline/{process_interface_factory_mongod.cpp => process_interface/mongod_process_interface_factory.cpp} (84%)
 rename src/mongo/db/pipeline/{ => process_interface}/mongos_process_interface.cpp (93%)
 rename src/mongo/db/pipeline/{ => process_interface}/mongos_process_interface.h (97%)
 rename src/mongo/db/pipeline/{ => process_interface}/mongos_process_interface_test.cpp (84%)
 create mode 100644 src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.cpp
 create mode 100644 src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h
 rename src/mongo/db/pipeline/{process_interface_shardsvr.cpp => process_interface/shardsvr_process_interface.cpp} (88%)
 rename src/mongo/db/pipeline/{process_interface_shardsvr.h => process_interface/shardsvr_process_interface.h} (95%)
 rename src/mongo/db/pipeline/{process_interface_standalone_test.cpp => process_interface/shardsvr_process_interface_test.cpp} (95%)
 rename src/mongo/db/pipeline/{stub_mongo_process_interface_lookup_single_document.cpp => process_interface/stub_lookup_single_document_process_interface.cpp} (89%)
 rename src/mongo/db/pipeline/{stub_mongo_process_interface_lookup_single_document.h => process_interface/stub_lookup_single_document_process_interface.h} (93%)
 rename src/mongo/db/pipeline/{ => process_interface}/stub_mongo_process_interface.h (99%)

46 files changed, 650 insertions, 535 deletions

diff --git a/src/mongo/SConscript b/src/mongo/SConscript
index db471f1d1a9..a448c09148f 100644
--- a/src/mongo/SConscript
+++ b/src/mongo/SConscript
@@ -404,7 +404,7 @@ mongod = env.Program(
         'db/periodic_runner_job_abort_expired_transactions',
         'db/periodic_runner_job_decrease_snapshot_cache_pressure',
         'db/pipeline/aggregation',
-        'db/pipeline/process_interface_factory_mongod',
+        'db/pipeline/process_interface/mongod_process_interface_factory',
         'db/query_exec',
         'db/read_concern_d_impl',
         'db/read_write_concern_defaults',
diff --git a/src/mongo/db/commands/SConscript b/src/mongo/db/commands/SConscript
index 740d41d2bd6..7e90c43ec11 100644
--- a/src/mongo/db/commands/SConscript
+++ b/src/mongo/db/commands/SConscript
@@ -301,9 +301,9 @@ env.Library(
         '$BUILD_DIR/mongo/db/curop_failpoint_helpers',
         '$BUILD_DIR/mongo/db/index_builds_coordinator_interface',
         '$BUILD_DIR/mongo/db/ops/write_ops_exec',
-        '$BUILD_DIR/mongo/db/pipeline/mongo_process_interface',
-        '$BUILD_DIR/mongo/db/query_exec',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongo_process_interface',
         '$BUILD_DIR/mongo/db/query/command_request_response',
+        '$BUILD_DIR/mongo/db/query_exec',
         '$BUILD_DIR/mongo/db/repl/replica_set_messages',
         '$BUILD_DIR/mongo/db/rw_concern_d',
         '$BUILD_DIR/mongo/db/stats/counters',
@@ -393,8 +393,8 @@ env.Library(
         '$BUILD_DIR/mongo/db/auth/authprivilege',
         '$BUILD_DIR/mongo/db/auth/role_graph',
         '$BUILD_DIR/mongo/db/auth/sasl_options',
-        '$BUILD_DIR/mongo/db/auth/user_document_parser',
         '$BUILD_DIR/mongo/db/auth/user',
+        '$BUILD_DIR/mongo/db/auth/user_document_parser',
         '$BUILD_DIR/mongo/db/background',
         '$BUILD_DIR/mongo/db/catalog/catalog_control',
         '$BUILD_DIR/mongo/db/catalog/catalog_helpers',
@@ -406,8 +406,8 @@ env.Library(
         '$BUILD_DIR/mongo/db/dbhelpers',
         '$BUILD_DIR/mongo/db/exec/stagedebug_cmd',
         '$BUILD_DIR/mongo/db/index_builds_coordinator_interface',
-        '$BUILD_DIR/mongo/db/pipeline/mongo_process_interface',
         '$BUILD_DIR/mongo/db/pipeline/pipeline',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongo_process_interface',
         '$BUILD_DIR/mongo/db/repl/dbcheck',
         '$BUILD_DIR/mongo/db/repl/oplog',
         '$BUILD_DIR/mongo/db/repl/repl_coordinator_interface',
@@ -524,8 +524,8 @@ env.Library(
         '$BUILD_DIR/mongo/db/commands/servers',
         '$BUILD_DIR/mongo/db/db_raii',
         '$BUILD_DIR/mongo/db/index/index_access_methods',
-        '$BUILD_DIR/mongo/db/pipeline/mongo_process_interface',
-        '$BUILD_DIR/mongo/db/pipeline/process_interface_factory_mongod',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongo_process_interface',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongod_process_interface_factory',
         '$BUILD_DIR/mongo/db/query_exec',
         '$BUILD_DIR/mongo/db/query/map_reduce_output_format',
         '$BUILD_DIR/mongo/idl/idl_parser',
diff --git a/src/mongo/db/commands/run_aggregate.cpp b/src/mongo/db/commands/run_aggregate.cpp
index d37112a4d34..2e951f66970 100644
--- a/src/mongo/db/commands/run_aggregate.cpp
+++ b/src/mongo/db/commands/run_aggregate.cpp
@@ -53,9 +53,9 @@
 #include "mongo/db/pipeline/expression.h"
 #include "mongo/db/pipeline/expression_context.h"
 #include "mongo/db/pipeline/lite_parsed_pipeline.h"
-#include "mongo/db/pipeline/mongo_process_interface.h"
 #include "mongo/db/pipeline/pipeline.h"
 #include "mongo/db/pipeline/pipeline_d.h"
+#include "mongo/db/pipeline/process_interface/mongo_process_interface.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
 #include "mongo/db/query/collection_query_info.h"
 #include "mongo/db/query/cursor_response.h"
diff --git a/src/mongo/db/pipeline/SConscript b/src/mongo/db/pipeline/SConscript
index 004469afc0e..2905a7d808b 100644
--- a/src/mongo/db/pipeline/SConscript
+++ b/src/mongo/db/pipeline/SConscript
@@ -4,6 +4,15 @@ Import('env')
 
 env = env.Clone()
 
+env.SConscript(
+    dirs=[
+        'process_interface',
+    ],
+    exports=[
+        'env',
+    ],
+)
+
 env.Library(
     target='aggregation',
     source=[
@@ -145,7 +154,7 @@ env.Library(
     target='document_source_mock',
     source=[
         'document_source_mock.cpp',
-        'stub_mongo_process_interface_lookup_single_document.cpp',
+        'process_interface/stub_lookup_single_document_process_interface.cpp',
         ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/db/query/query_test_service_context',
@@ -178,93 +187,6 @@ env.Library(
 )
 
 env.Library(
-    target='mongo_process_interface',
-    source=[
-        'mongo_process_interface.cpp',
-    ],
-    LIBDEPS=[
-        '$BUILD_DIR/mongo/base',
-    ]
-)
-
-env.Library(
-    target='mongo_process_common',
-    source=[
-        'mongo_process_common.cpp',
-    ],
-    LIBDEPS=[
-        '$BUILD_DIR/mongo/db/auth/auth',
-        '$BUILD_DIR/mongo/db/generic_cursor',
-        '$BUILD_DIR/mongo/s/sharding_router_api',
-        'field_path',
-    ]
-)
-
-env.Library(
-    target='process_interface_standalone',
-    source=[
-        'process_interface_standalone.cpp',
-    ],
-    LIBDEPS=[
-        '$BUILD_DIR/mongo/db/catalog/catalog_helpers',
-        '$BUILD_DIR/mongo/db/ops/write_ops_exec',
-        '$BUILD_DIR/mongo/db/query_exec',
-        '$BUILD_DIR/mongo/db/repl/speculative_majority_read_info',
-        'mongo_process_common',
-    ],
-    LIBDEPS_PRIVATE=[
-        '$BUILD_DIR/mongo/db/catalog/database_holder',
-        '$BUILD_DIR/mongo/db/concurrency/flow_control_ticketholder',
-        '$BUILD_DIR/mongo/db/index_builds_coordinator_interface',
-        '$BUILD_DIR/mongo/db/session_catalog',
-        '$BUILD_DIR/mongo/db/storage/backup_cursor_hooks',
-        '$BUILD_DIR/mongo/db/transaction',
-        '$BUILD_DIR/mongo/scripting/scripting_common',
-    ],
-)
-
-env.Library(
-    target='process_interface_shardsvr',
-    source=[
-        'process_interface_shardsvr.cpp',
-    ],
-    LIBDEPS=[
-        '$BUILD_DIR/mongo/db/transaction',
-        '$BUILD_DIR/mongo/db/write_ops',
-        '$BUILD_DIR/mongo/s/sharding_api',
-        'process_interface_standalone',
-        'sharded_agg_helpers',
-    ],
-)
-
-env.Library(
-    target='mongos_process_interface',
-    source=[
-        'mongos_process_interface.cpp',
-    ],
-    LIBDEPS=[
-        '$BUILD_DIR/mongo/db/pipeline/pipeline',
-        '$BUILD_DIR/mongo/s/query/async_results_merger',
-        '$BUILD_DIR/mongo/s/query/cluster_query',
-        'mongo_process_common',
-        'sharded_agg_helpers',
-    ],
-    LIBDEPS_PRIVATE=[
-        '$BUILD_DIR/mongo/db/session_catalog',
-    ],
-)
-
-env.Library(
-    target="process_interface_factory_mongod",
-    source=[
-        "process_interface_factory_mongod.cpp",
-    ],
-    LIBDEPS_PRIVATE=[
-        'process_interface_shardsvr',
-    ],
-)
-
-env.Library(
     target="document_path_support",
     source=[
         'document_path_support.cpp',
@@ -469,10 +391,8 @@ env.CppUnitTest(
         'granularity_rounder_powers_of_two_test.cpp',
         'granularity_rounder_preferred_numbers_test.cpp',
         'lookup_set_cache_test.cpp',
-        'mongos_process_interface_test.cpp',
         'pipeline_metadata_tree_test.cpp',
         'pipeline_test.cpp',
-        'process_interface_standalone_test.cpp',
         'resume_token_test.cpp',
         'semantic_analysis_test.cpp',
         'sequential_document_cache_test.cpp',
@@ -503,11 +423,9 @@ env.CppUnitTest(
         'expression',
         'field_path',
         'granularity_rounder',
-        'mongo_process_common',
-        'mongo_process_interface',
-        'mongos_process_interface',
         'pipeline',
-        'process_interface_shardsvr',
-        'process_interface_standalone',
+        'process_interface/mongod_process_interfaces',
+        'process_interface/mongos_process_interface',
+        'sharded_agg_helpers',
     ]
 )
diff --git a/src/mongo/db/pipeline/accumulator_js_test.cpp b/src/mongo/db/pipeline/accumulator_js_test.cpp
index 41f12ac8898..6c5f2b6127b 100644
--- a/src/mongo/db/pipeline/accumulator_js_test.cpp
+++ b/src/mongo/db/pipeline/accumulator_js_test.cpp
@@ -35,7 +35,7 @@
 #include "mongo/db/exec/document_value/document_value_test_util.h"
 #include "mongo/db/pipeline/accumulator_js_reduce.h"
 #include "mongo/db/pipeline/expression_context_for_test.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
 #include "mongo/db/service_context_d_test_fixture.h"
 #include "mongo/dbtests/dbtests.h"
 #include "mongo/scripting/engine.h"
@@ -46,7 +46,8 @@ namespace {
 class MapReduceFixture : public ServiceContextMongoDTest {
 protected:
     MapReduceFixture() : _expCtx((new ExpressionContextForTest())) {
-        _expCtx->mongoProcessInterface = std::make_shared<MongoInterfaceStandalone>(_expCtx->opCtx);
+        _expCtx->mongoProcessInterface =
+            std::make_shared<NonShardServerProcessInterface>(_expCtx->opCtx);
     }
 
     boost::intrusive_ptr<ExpressionContextForTest>& getExpCtx() {
diff --git a/src/mongo/db/pipeline/document_source_change_stream_test.cpp b/src/mongo/db/pipeline/document_source_change_stream_test.cpp
index 1e37a101baf..de0e757ab69 100644
--- a/src/mongo/db/pipeline/document_source_change_stream_test.cpp
+++ b/src/mongo/db/pipeline/document_source_change_stream_test.cpp
@@ -50,7 +50,7 @@
 #include "mongo/db/pipeline/document_source_match.h"
 #include "mongo/db/pipeline/document_source_mock.h"
 #include "mongo/db/pipeline/document_source_sort.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/repl/oplog_entry.h"
 #include "mongo/db/repl/replication_coordinator_mock.h"
 #include "mongo/db/transaction_history_iterator.h"
diff --git a/src/mongo/db/pipeline/document_source_check_resume_token_test.cpp b/src/mongo/db/pipeline/document_source_check_resume_token_test.cpp
index 38f8ad2b2f3..044afa7b5a9 100644
--- a/src/mongo/db/pipeline/document_source_check_resume_token_test.cpp
+++ b/src/mongo/db/pipeline/document_source_check_resume_token_test.cpp
@@ -40,8 +40,8 @@
 #include "mongo/db/pipeline/document_source_check_resume_token.h"
 #include "mongo/db/pipeline/document_source_mock.h"
 #include "mongo/db/pipeline/expression_context.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/pipeline/resume_token.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
 #include "mongo/db/query/collation/collator_interface_mock.h"
 #include "mongo/db/service_context.h"
 #include "mongo/unittest/death_test.h"
diff --git a/src/mongo/db/pipeline/document_source_current_op_test.cpp b/src/mongo/db/pipeline/document_source_current_op_test.cpp
index a2fb9ed833a..260bfbf0829 100644
--- a/src/mongo/db/pipeline/document_source_current_op_test.cpp
+++ b/src/mongo/db/pipeline/document_source_current_op_test.cpp
@@ -33,7 +33,7 @@
 #include "mongo/db/exec/document_value/document_value_test_util.h"
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
 #include "mongo/db/pipeline/document_source_current_op.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/unittest/unittest.h"
 #include "mongo/util/assert_util.h"
 #include "mongo/util/str.h"
diff --git a/src/mongo/db/pipeline/document_source_graph_lookup_test.cpp b/src/mongo/db/pipeline/document_source_graph_lookup_test.cpp
index a408be7580e..a3996c47480 100644
--- a/src/mongo/db/pipeline/document_source_graph_lookup_test.cpp
+++ b/src/mongo/db/pipeline/document_source_graph_lookup_test.cpp
@@ -37,7 +37,7 @@
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
 #include "mongo/db/pipeline/document_source_graph_lookup.h"
 #include "mongo/db/pipeline/document_source_mock.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/unittest/unittest.h"
 #include "mongo/util/assert_util.h"
 #include "mongo/util/str.h"
diff --git a/src/mongo/db/pipeline/document_source_lookup_change_post_image_test.cpp b/src/mongo/db/pipeline/document_source_lookup_change_post_image_test.cpp
index 7f8d624848b..554d308d237 100644
--- a/src/mongo/db/pipeline/document_source_lookup_change_post_image_test.cpp
+++ b/src/mongo/db/pipeline/document_source_lookup_change_post_image_test.cpp
@@ -44,7 +44,7 @@
 #include "mongo/db/pipeline/document_source_lookup_change_post_image.h"
 #include "mongo/db/pipeline/document_source_mock.h"
 #include "mongo/db/pipeline/field_path.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.h"
+#include "mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.h"
 
 namespace mongo {
 namespace {
@@ -52,7 +52,7 @@ using boost::intrusive_ptr;
 using std::deque;
 using std::vector;
 
-using MockMongoInterface = StubMongoProcessInterfaceLookupSingleDocument;
+using MockMongoInterface = StubLookupSingleDocumentProcessInterface;
 
 // This provides access to getExpCtx(), but we'll use a different name for this test suite.
 class DocumentSourceLookupChangePostImageTest : public AggregationContextFixture {
diff --git a/src/mongo/db/pipeline/document_source_lookup_test.cpp b/src/mongo/db/pipeline/document_source_lookup_test.cpp
index a4993f706ca..ae0f329e14f 100644
--- a/src/mongo/db/pipeline/document_source_lookup_test.cpp
+++ b/src/mongo/db/pipeline/document_source_lookup_test.cpp
@@ -43,7 +43,7 @@
 #include "mongo/db/pipeline/document_source_lookup.h"
 #include "mongo/db/pipeline/document_source_mock.h"
 #include "mongo/db/pipeline/field_path.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/query/query_knobs_gen.h"
 #include "mongo/db/repl/replication_coordinator_mock.h"
 #include "mongo/db/repl/storage_interface_mock.h"
diff --git a/src/mongo/db/pipeline/document_source_merge_test.cpp b/src/mongo/db/pipeline/document_source_merge_test.cpp
index f309915462f..f78f3195ec1 100644
--- a/src/mongo/db/pipeline/document_source_merge_test.cpp
+++ b/src/mongo/db/pipeline/document_source_merge_test.cpp
@@ -35,7 +35,7 @@
 #include "mongo/db/exec/document_value/document_value_test_util.h"
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
 #include "mongo/db/pipeline/document_source_merge.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
 
 namespace mongo {
 namespace {
diff --git a/src/mongo/db/pipeline/document_source_plan_cache_stats_test.cpp b/src/mongo/db/pipeline/document_source_plan_cache_stats_test.cpp
index 47970d8c9e5..95f5c799b7c 100644
--- a/src/mongo/db/pipeline/document_source_plan_cache_stats_test.cpp
+++ b/src/mongo/db/pipeline/document_source_plan_cache_stats_test.cpp
@@ -34,7 +34,7 @@
 #include "mongo/bson/json.h"
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
 #include "mongo/db/pipeline/document_source_plan_cache_stats.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/unittest/unittest.h"
 
 namespace mongo {
diff --git a/src/mongo/db/pipeline/document_source_union_with_test.cpp b/src/mongo/db/pipeline/document_source_union_with_test.cpp
index a8fd3784573..90b6b9fefa4 100644
--- a/src/mongo/db/pipeline/document_source_union_with_test.cpp
+++ b/src/mongo/db/pipeline/document_source_union_with_test.cpp
@@ -46,14 +46,14 @@
 #include "mongo/db/pipeline/document_source_replace_root.h"
 #include "mongo/db/pipeline/document_source_union_with.h"
 #include "mongo/db/pipeline/pipeline.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.h"
+#include "mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.h"
 #include "mongo/unittest/unittest.h"
 #include "mongo/util/intrusive_counter.h"
 
 namespace mongo {
 namespace {
 
-using MockMongoInterface = StubMongoProcessInterfaceLookupSingleDocument;
+using MockMongoInterface = StubLookupSingleDocumentProcessInterface;
 
 // This provides access to getExpCtx(), but we'll use a different name for this test suite.
 using DocumentSourceUnionWithTest = AggregationContextFixture;
diff --git a/src/mongo/db/pipeline/expression_context.cpp b/src/mongo/db/pipeline/expression_context.cpp
index 1a9eb04e4ef..563b03569ab 100644
--- a/src/mongo/db/pipeline/expression_context.cpp
+++ b/src/mongo/db/pipeline/expression_context.cpp
@@ -32,7 +32,7 @@
 #include <utility>
 
 #include "mongo/db/pipeline/expression_context.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/query/collation/collation_spec.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
 #include "mongo/util/intrusive_counter.h"
diff --git a/src/mongo/db/pipeline/expression_context.h b/src/mongo/db/pipeline/expression_context.h
index 6fde76c2c07..b0f4df41e05 100644
--- a/src/mongo/db/pipeline/expression_context.h
+++ b/src/mongo/db/pipeline/expression_context.h
@@ -43,7 +43,7 @@
 #include "mongo/db/operation_context.h"
 #include "mongo/db/pipeline/aggregation_request.h"
 #include "mongo/db/pipeline/javascript_execution.h"
-#include "mongo/db/pipeline/mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongo_process_interface.h"
 #include "mongo/db/pipeline/runtime_constants_gen.h"
 #include "mongo/db/pipeline/variables.h"
 #include "mongo/db/query/collation/collator_interface.h"
diff --git a/src/mongo/db/pipeline/expression_context_for_test.h b/src/mongo/db/pipeline/expression_context_for_test.h
index d716469f6e7..f5cbf88b799 100644
--- a/src/mongo/db/pipeline/expression_context_for_test.h
+++ b/src/mongo/db/pipeline/expression_context_for_test.h
@@ -32,7 +32,7 @@
 #include <boost/optional.hpp>
 
 #include "mongo/db/pipeline/expression_context.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/query/datetime/date_time_support.h"
 #include "mongo/db/query/query_test_service_context.h"
 
diff --git a/src/mongo/db/pipeline/expression_javascript_test.cpp b/src/mongo/db/pipeline/expression_javascript_test.cpp
index e921d15fa65..43539f7bf75 100644
--- a/src/mongo/db/pipeline/expression_javascript_test.cpp
+++ b/src/mongo/db/pipeline/expression_javascript_test.cpp
@@ -33,7 +33,7 @@
 #include "mongo/db/exec/document_value/document.h"
 #include "mongo/db/exec/document_value/document_value_test_util.h"
 #include "mongo/db/pipeline/expression_context_for_test.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
 #include "mongo/db/query/query_knobs_gen.h"
 #include "mongo/db/service_context_d_test_fixture.h"
 #include "mongo/scripting/engine.h"
@@ -46,7 +46,8 @@ class MapReduceFixture : public ServiceContextMongoDTest {
 protected:
     MapReduceFixture()
         : _expCtx((new ExpressionContextForTest())), _vps(_expCtx->variablesParseState) {
-        _expCtx->mongoProcessInterface = std::make_shared<MongoInterfaceStandalone>(_expCtx->opCtx);
+        _expCtx->mongoProcessInterface =
+            std::make_shared<NonShardServerProcessInterface>(_expCtx->opCtx);
     }
 
     boost::intrusive_ptr<ExpressionContextForTest>& getExpCtx() {
diff --git a/src/mongo/db/pipeline/pipeline_test.cpp b/src/mongo/db/pipeline/pipeline_test.cpp
index c94058843b2..a657912b6a7 100644
--- a/src/mongo/db/pipeline/pipeline_test.cpp
+++ b/src/mongo/db/pipeline/pipeline_test.cpp
@@ -54,9 +54,9 @@
 #include "mongo/db/pipeline/expression_context_for_test.h"
 #include "mongo/db/pipeline/field_path.h"
 #include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/pipeline/semantic_analysis.h"
 #include "mongo/db/pipeline/sharded_agg_helpers.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
 #include "mongo/db/query/collation/collator_interface_mock.h"
 #include "mongo/db/query/query_test_service_context.h"
 #include "mongo/db/repl/replication_coordinator_mock.h"
diff --git a/src/mongo/db/pipeline/process_interface/SConscript b/src/mongo/db/pipeline/process_interface/SConscript
new file mode 100644
index 00000000000..0a19c65c996
--- /dev/null
+++ b/src/mongo/db/pipeline/process_interface/SConscript
@@ -0,0 +1,111 @@
+# -*- mode: python -*-
+
+Import('env')
+
+env = env.Clone()
+
+env.Library(
+    target='mongo_process_interface',
+    source=[
+        'mongo_process_interface.cpp',
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/base',
+    ],
+)
+
+env.Library(
+    target='common_process_interface',
+    source=[
+        'common_process_interface.cpp',
+    ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/auth/auth',	
+        '$BUILD_DIR/mongo/db/generic_cursor',	
+        '$BUILD_DIR/mongo/db/pipeline/field_path',
+        '$BUILD_DIR/mongo/s/sharding_router_api',	
+    ],
+)
+
+# This library is the basic mongod functionality, depended on by embedded so designed to exclude
+# large components like sharding and networking.
+env.Library(
+    target='mongod_process_interfaces',
+    source=[
+        'common_mongod_process_interface.cpp',
+        'non_shardsvr_process_interface.cpp',
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/db/ops/write_ops_exec',
+        '$BUILD_DIR/mongo/db/pipeline/pipeline',
+        '$BUILD_DIR/mongo/db/transaction',
+        '$BUILD_DIR/mongo/db/write_ops',
+        'common_process_interface',
+    ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/catalog/catalog_helpers',
+        '$BUILD_DIR/mongo/db/catalog/database_holder',
+        '$BUILD_DIR/mongo/db/concurrency/flow_control_ticketholder',
+        '$BUILD_DIR/mongo/db/index_builds_coordinator_mongod',
+        '$BUILD_DIR/mongo/db/session_catalog',
+        '$BUILD_DIR/mongo/db/storage/backup_cursor_hooks',
+        '$BUILD_DIR/mongo/db/transaction',
+        '$BUILD_DIR/mongo/scripting/scripting_common',
+    ],
+)
+
+env.Library(
+    target="shardsvr_process_interface",
+    source=[
+        'shardsvr_process_interface.cpp',
+    ],
+    LIBDEPS=[
+        'mongod_process_interfaces',
+    ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/pipeline/sharded_agg_helpers',
+        '$BUILD_DIR/mongo/s/sharding_api',
+    ],
+)
+
+env.Library(
+    target='mongod_process_interface_factory',
+    source=[
+        'mongod_process_interface_factory.cpp',
+    ],
+    LIBDEPS=[
+        'mongod_process_interfaces',
+        'shardsvr_process_interface',
+    ],
+)
+
+env.Library(
+    target='mongos_process_interface',
+    source=[
+        'mongos_process_interface.cpp',
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/db/pipeline/pipeline',
+        '$BUILD_DIR/mongo/s/query/async_results_merger',
+        '$BUILD_DIR/mongo/s/query/cluster_query',
+        'common_process_interface',
+    ],
+    LIBDEPS_PRIVATE=[
+        '$BUILD_DIR/mongo/db/session_catalog',
+        '$BUILD_DIR/mongo/db/pipeline/sharded_agg_helpers',
+    ],
+)
+
+env.CppUnitTest(
+    target='process_interface_test',
+    source=[
+        'mongos_process_interface_test.cpp',
+        'shardsvr_process_interface_test.cpp',
+    ],
+    LIBDEPS=[
+        '$BUILD_DIR/mongo/db/query/query_test_service_context',
+        '$BUILD_DIR/mongo/db/service_context_test_fixture',
+        'mongos_process_interface',
+        'shardsvr_process_interface',
+    ]
+)
diff --git a/src/mongo/db/pipeline/process_interface_standalone.cpp b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp
index 57e41991379..483b20cd702 100644
--- a/src/mongo/db/pipeline/process_interface_standalone.cpp
+++ b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.cpp
@@ -31,7 +31,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/common_mongod_process_interface.h"
 
 #include "mongo/db/auth/authorization_session.h"
 #include "mongo/db/catalog/collection.h"
@@ -49,7 +49,6 @@
 #include "mongo/db/cursor_manager.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/index/index_descriptor.h"
-#include "mongo/db/index_builds_coordinator.h"
 #include "mongo/db/pipeline/document_source_cursor.h"
 #include "mongo/db/pipeline/lite_parsed_pipeline.h"
 #include "mongo/db/pipeline/pipeline_d.h"
@@ -73,14 +72,6 @@
 
 namespace mongo {
 
-using boost::intrusive_ptr;
-using std::shared_ptr;
-using std::string;
-using std::unique_ptr;
-using write_ops::Insert;
-using write_ops::Update;
-using write_ops::UpdateOpEntry;
-
 namespace {
 
 class MongoDResourceYielder : public ResourceYielder {
@@ -152,117 +143,26 @@ bool supportsUniqueKey(const boost::intrusive_ptr<ExpressionContext>& expCtx,
 
 }  // namespace
 
-MongoInterfaceStandalone::MongoInterfaceStandalone(OperationContext* opCtx) {}
+CommonMongodProcessInterface::CommonMongodProcessInterface(OperationContext* opCtx) {}
 
 std::unique_ptr<TransactionHistoryIteratorBase>
-MongoInterfaceStandalone::createTransactionHistoryIterator(repl::OpTime time) const {
+CommonMongodProcessInterface::createTransactionHistoryIterator(repl::OpTime time) const {
     bool permitYield = true;
     return std::unique_ptr<TransactionHistoryIteratorBase>(
         new TransactionHistoryIterator(time, permitYield));
 }
 
-bool MongoInterfaceStandalone::isSharded(OperationContext* opCtx, const NamespaceString& nss) {
+bool CommonMongodProcessInterface::isSharded(OperationContext* opCtx, const NamespaceString& nss) {
     Lock::DBLock dbLock(opCtx, nss.db(), MODE_IS);
     Lock::CollectionLock collLock(opCtx, nss, MODE_IS);
     const auto metadata = CollectionShardingState::get(opCtx, nss)->getCurrentMetadata();
     return metadata->isSharded();
 }
 
-Insert MongoInterfaceStandalone::buildInsertOp(const NamespaceString& nss,
-                                               std::vector<BSONObj>&& objs,
-                                               bool bypassDocValidation) {
-    Insert insertOp(nss);
-    insertOp.setDocuments(std::move(objs));
-    insertOp.setWriteCommandBase([&] {
-        write_ops::WriteCommandBase wcb;
-        wcb.setOrdered(false);
-        wcb.setBypassDocumentValidation(bypassDocValidation);
-        return wcb;
-    }());
-    return insertOp;
-}
-
-Update MongoInterfaceStandalone::buildUpdateOp(
-    const boost::intrusive_ptr<ExpressionContext>& expCtx,
-    const NamespaceString& nss,
-    BatchedObjects&& batch,
-    UpsertType upsert,
-    bool multi) {
-    Update updateOp(nss);
-    updateOp.setUpdates([&] {
-        std::vector<UpdateOpEntry> updateEntries;
-        for (auto&& obj : batch) {
-            updateEntries.push_back([&] {
-                UpdateOpEntry entry;
-                auto&& [q, u, c] = obj;
-                entry.setQ(std::move(q));
-                entry.setU(std::move(u));
-                entry.setC(std::move(c));
-                entry.setUpsert(upsert != UpsertType::kNone);
-                // TODO SERVER-44884: after branching for 4.5, remove the 'useNewUpsert' flag.
-                entry.setUpsertSupplied({{entry.getUpsert() && expCtx->useNewUpsert,
-                                          upsert == UpsertType::kInsertSuppliedDoc}});
-                entry.setMulti(multi);
-                return entry;
-            }());
-        }
-        return updateEntries;
-    }());
-    updateOp.setWriteCommandBase([&] {
-        write_ops::WriteCommandBase wcb;
-        wcb.setOrdered(false);
-        wcb.setBypassDocumentValidation(expCtx->bypassDocumentValidation);
-        return wcb;
-    }());
-    updateOp.setRuntimeConstants(expCtx->getRuntimeConstants());
-    return updateOp;
-}
-
-Status MongoInterfaceStandalone::insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                                        const NamespaceString& ns,
-                                        std::vector<BSONObj>&& objs,
-                                        const WriteConcernOptions& wc,
-                                        boost::optional<OID> targetEpoch) {
-    auto writeResults = performInserts(
-        expCtx->opCtx, buildInsertOp(ns, std::move(objs), expCtx->bypassDocumentValidation));
-
-    // Need to check each result in the batch since the writes are unordered.
-    for (const auto& result : writeResults.results) {
-        if (result.getStatus() != Status::OK()) {
-            return result.getStatus();
-        }
-    }
-    return Status::OK();
-}
-
-StatusWith<MongoProcessInterface::UpdateResult> MongoInterfaceStandalone::update(
-    const boost::intrusive_ptr<ExpressionContext>& expCtx,
-    const NamespaceString& ns,
-    BatchedObjects&& batch,
-    const WriteConcernOptions& wc,
-    UpsertType upsert,
-    bool multi,
-    boost::optional<OID> targetEpoch) {
-    auto writeResults =
-        performUpdates(expCtx->opCtx, buildUpdateOp(expCtx, ns, std::move(batch), upsert, multi));
-
-    // Need to check each result in the batch since the writes are unordered.
-    UpdateResult updateResult;
-    for (const auto& result : writeResults.results) {
-        if (result.getStatus() != Status::OK()) {
-            return result.getStatus();
-        }
-
-        updateResult.nMatched += result.getValue().getN();
-        updateResult.nModified += result.getValue().getNModified();
-    }
-    return updateResult;
-}
-
-std::vector<Document> MongoInterfaceStandalone::getIndexStats(OperationContext* opCtx,
-                                                              const NamespaceString& ns,
-                                                              StringData host,
-                                                              bool addShardName) {
+std::vector<Document> CommonMongodProcessInterface::getIndexStats(OperationContext* opCtx,
+                                                                  const NamespaceString& ns,
+                                                                  StringData host,
+                                                                  bool addShardName) {
     AutoGetCollectionForReadCommand autoColl(opCtx, ns);
 
     Collection* collection = autoColl.getCollection();
@@ -306,35 +206,29 @@ std::vector<Document> MongoInterfaceStandalone::getIndexStats(OperationContext*
     return indexStats;
 }
 
-std::list<BSONObj> MongoInterfaceStandalone::getIndexSpecs(OperationContext* opCtx,
-                                                           const NamespaceString& ns,
-                                                           bool includeBuildUUIDs) {
-    return listIndexesEmptyListIfMissing(opCtx, ns, includeBuildUUIDs);
-}
-
-void MongoInterfaceStandalone::appendLatencyStats(OperationContext* opCtx,
-                                                  const NamespaceString& nss,
-                                                  bool includeHistograms,
-                                                  BSONObjBuilder* builder) const {
+void CommonMongodProcessInterface::appendLatencyStats(OperationContext* opCtx,
+                                                      const NamespaceString& nss,
+                                                      bool includeHistograms,
+                                                      BSONObjBuilder* builder) const {
     Top::get(opCtx->getServiceContext()).appendLatencyStats(nss, includeHistograms, builder);
 }
 
-Status MongoInterfaceStandalone::appendStorageStats(OperationContext* opCtx,
-                                                    const NamespaceString& nss,
-                                                    const BSONObj& param,
-                                                    BSONObjBuilder* builder) const {
+Status CommonMongodProcessInterface::appendStorageStats(OperationContext* opCtx,
+                                                        const NamespaceString& nss,
+                                                        const BSONObj& param,
+                                                        BSONObjBuilder* builder) const {
     return appendCollectionStorageStats(opCtx, nss, param, builder);
 }
 
-Status MongoInterfaceStandalone::appendRecordCount(OperationContext* opCtx,
-                                                   const NamespaceString& nss,
-                                                   BSONObjBuilder* builder) const {
+Status CommonMongodProcessInterface::appendRecordCount(OperationContext* opCtx,
+                                                       const NamespaceString& nss,
+                                                       BSONObjBuilder* builder) const {
     return appendCollectionRecordCount(opCtx, nss, builder);
 }
 
-Status MongoInterfaceStandalone::appendQueryExecStats(OperationContext* opCtx,
-                                                      const NamespaceString& nss,
-                                                      BSONObjBuilder* builder) const {
+Status CommonMongodProcessInterface::appendQueryExecStats(OperationContext* opCtx,
+                                                          const NamespaceString& nss,
+                                                          BSONObjBuilder* builder) const {
     AutoGetCollectionForReadCommand autoColl(opCtx, nss);
 
     if (!autoColl.getDb()) {
@@ -365,8 +259,8 @@ Status MongoInterfaceStandalone::appendQueryExecStats(OperationContext* opCtx,
     return Status::OK();
 }
 
-BSONObj MongoInterfaceStandalone::getCollectionOptions(OperationContext* opCtx,
-                                                       const NamespaceString& nss) {
+BSONObj CommonMongodProcessInterface::getCollectionOptions(OperationContext* opCtx,
+                                                           const NamespaceString& nss) {
     AutoGetCollectionForReadCommand autoColl(opCtx, nss);
     BSONObj collectionOptions = {};
     if (!autoColl.getDb()) {
@@ -383,67 +277,7 @@ BSONObj MongoInterfaceStandalone::getCollectionOptions(OperationContext* opCtx,
     return collectionOptions;
 }
 
-void MongoInterfaceStandalone::renameIfOptionsAndIndexesHaveNotChanged(
-    OperationContext* opCtx,
-    const BSONObj& renameCommandObj,
-    const NamespaceString& targetNs,
-    const BSONObj& originalCollectionOptions,
-    const std::list<BSONObj>& originalIndexes) {
-    NamespaceString sourceNs = NamespaceString(renameCommandObj["renameCollection"].String());
-    doLocalRenameIfOptionsAndIndexesHaveNotChanged(opCtx,
-                                                   sourceNs,
-                                                   targetNs,
-                                                   renameCommandObj["dropTarget"].trueValue(),
-                                                   renameCommandObj["stayTemp"].trueValue(),
-                                                   originalIndexes,
-                                                   originalCollectionOptions);
-}
-
-void MongoInterfaceStandalone::createCollection(OperationContext* opCtx,
-                                                const std::string& dbName,
-                                                const BSONObj& cmdObj) {
-    uassertStatusOK(mongo::createCollection(opCtx, dbName, cmdObj));
-}
-
-void MongoInterfaceStandalone::createIndexesOnEmptyCollection(
-    OperationContext* opCtx, const NamespaceString& ns, const std::vector<BSONObj>& indexSpecs) {
-    AutoGetCollection autoColl(opCtx, ns, MODE_X);
-    writeConflictRetry(
-        opCtx, "MongoInterfaceStandalone::createIndexesOnEmptyCollection", ns.ns(), [&] {
-            auto collection = autoColl.getCollection();
-            invariant(collection,
-                      str::stream() << "Failed to create indexes for aggregation because "
-                                       "collection does not exist: "
-                                    << ns << ": " << BSON("indexes" << indexSpecs));
-
-            invariant(0U == collection->numRecords(opCtx),
-                      str::stream() << "Expected empty collection for index creation: " << ns
-                                    << ": numRecords: " << collection->numRecords(opCtx) << ": "
-                                    << BSON("indexes" << indexSpecs));
-
-            // Secondary index builds do not filter existing indexes so we have to do this on the
-            // primary.
-            auto removeIndexBuildsToo = false;
-            auto filteredIndexes = collection->getIndexCatalog()->removeExistingIndexes(
-                opCtx, indexSpecs, removeIndexBuildsToo);
-            if (filteredIndexes.empty()) {
-                return;
-            }
-
-            WriteUnitOfWork wuow(opCtx);
-            IndexBuildsCoordinator::get(opCtx)->createIndexesOnEmptyCollection(
-                opCtx, collection->uuid(), filteredIndexes, false  // fromMigrate
-            );
-            wuow.commit();
-        });
-}
-void MongoInterfaceStandalone::dropCollection(OperationContext* opCtx, const NamespaceString& ns) {
-    BSONObjBuilder result;
-    uassertStatusOK(mongo::dropCollection(
-        opCtx, ns, result, {}, DropCollectionSystemCollectionMode::kDisallowSystemCollectionDrops));
-}
-
-std::unique_ptr<Pipeline, PipelineDeleter> MongoInterfaceStandalone::makePipeline(
+std::unique_ptr<Pipeline, PipelineDeleter> CommonMongodProcessInterface::makePipeline(
     const std::vector<BSONObj>& rawPipeline,
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const MakePipelineOptions opts) {
@@ -461,15 +295,8 @@ std::unique_ptr<Pipeline, PipelineDeleter> MongoInterfaceStandalone::makePipelin
     return pipeline;
 }
 
-unique_ptr<Pipeline, PipelineDeleter> MongoInterfaceStandalone::attachCursorSourceToPipeline(
-    const boost::intrusive_ptr<ExpressionContext>& expCtx,
-    Pipeline* ownedPipeline,
-    bool allowTargetingShards) {
-    return attachCursorSourceToPipelineForLocalRead(expCtx, ownedPipeline);
-}
-
-unique_ptr<Pipeline, PipelineDeleter>
-MongoInterfaceStandalone::attachCursorSourceToPipelineForLocalRead(
+std::unique_ptr<Pipeline, PipelineDeleter>
+CommonMongodProcessInterface::attachCursorSourceToPipelineForLocalRead(
     const boost::intrusive_ptr<ExpressionContext>& expCtx, Pipeline* ownedPipeline) {
     std::unique_ptr<Pipeline, PipelineDeleter> pipeline(ownedPipeline,
                                                         PipelineDeleter(expCtx->opCtx));
@@ -493,7 +320,7 @@ MongoInterfaceStandalone::attachCursorSourceToPipelineForLocalRead(
     return pipeline;
 }
 
-std::string MongoInterfaceStandalone::getShardName(OperationContext* opCtx) const {
+std::string CommonMongodProcessInterface::getShardName(OperationContext* opCtx) const {
     if (ShardingState::get(opCtx)->enabled()) {
         return ShardingState::get(opCtx)->shardId().toString();
     }
@@ -501,24 +328,12 @@ std::string MongoInterfaceStandalone::getShardName(OperationContext* opCtx) cons
     return std::string();
 }
 
-std::pair<std::vector<FieldPath>, bool>
-MongoInterfaceStandalone::collectDocumentKeyFieldsForHostedCollection(OperationContext* opCtx,
-                                                                      const NamespaceString& nss,
-                                                                      UUID uuid) const {
-    return {{"_id"}, false};  // Nothing is sharded.
-}
-
-std::vector<FieldPath> MongoInterfaceStandalone::collectDocumentKeyFieldsActingAsRouter(
-    OperationContext* opCtx, const NamespaceString& nss) const {
-    return {"_id"};  // Nothing is sharded.
-}
-
-std::vector<GenericCursor> MongoInterfaceStandalone::getIdleCursors(
-    const intrusive_ptr<ExpressionContext>& expCtx, CurrentOpUserMode userMode) const {
+std::vector<GenericCursor> CommonMongodProcessInterface::getIdleCursors(
+    const boost::intrusive_ptr<ExpressionContext>& expCtx, CurrentOpUserMode userMode) const {
     return CursorManager::get(expCtx->opCtx)->getIdleCursors(expCtx->opCtx, userMode);
 }
 
-boost::optional<Document> MongoInterfaceStandalone::lookupSingleDocument(
+boost::optional<Document> CommonMongodProcessInterface::lookupSingleDocument(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     UUID collectionUUID,
@@ -574,7 +389,7 @@ boost::optional<Document> MongoInterfaceStandalone::lookupSingleDocument(
     return lookedUpDocument;
 }
 
-BackupCursorState MongoInterfaceStandalone::openBackupCursor(
+BackupCursorState CommonMongodProcessInterface::openBackupCursor(
     OperationContext* opCtx, const StorageEngine::BackupOptions& options) {
     auto backupCursorHooks = BackupCursorHooks::get(opCtx->getServiceContext());
     if (backupCursorHooks->enabled()) {
@@ -584,7 +399,8 @@ BackupCursorState MongoInterfaceStandalone::openBackupCursor(
     }
 }
 
-void MongoInterfaceStandalone::closeBackupCursor(OperationContext* opCtx, const UUID& backupId) {
+void CommonMongodProcessInterface::closeBackupCursor(OperationContext* opCtx,
+                                                     const UUID& backupId) {
     auto backupCursorHooks = BackupCursorHooks::get(opCtx->getServiceContext());
     if (backupCursorHooks->enabled()) {
         backupCursorHooks->closeBackupCursor(opCtx, backupId);
@@ -593,9 +409,8 @@ void MongoInterfaceStandalone::closeBackupCursor(OperationContext* opCtx, const
     }
 }
 
-BackupCursorExtendState MongoInterfaceStandalone::extendBackupCursor(OperationContext* opCtx,
-                                                                     const UUID& backupId,
-                                                                     const Timestamp& extendTo) {
+BackupCursorExtendState CommonMongodProcessInterface::extendBackupCursor(
+    OperationContext* opCtx, const UUID& backupId, const Timestamp& extendTo) {
     auto backupCursorHooks = BackupCursorHooks::get(opCtx->getServiceContext());
     if (backupCursorHooks->enabled()) {
         return backupCursorHooks->extendBackupCursor(opCtx, backupId, extendTo);
@@ -604,7 +419,7 @@ BackupCursorExtendState MongoInterfaceStandalone::extendBackupCursor(OperationCo
     }
 }
 
-std::vector<BSONObj> MongoInterfaceStandalone::getMatchingPlanCacheEntryStats(
+std::vector<BSONObj> CommonMongodProcessInterface::getMatchingPlanCacheEntryStats(
     OperationContext* opCtx, const NamespaceString& nss, const MatchExpression* matchExp) const {
     const auto serializer = [](const PlanCacheEntry& entry) {
         BSONObjBuilder out;
@@ -627,7 +442,7 @@ std::vector<BSONObj> MongoInterfaceStandalone::getMatchingPlanCacheEntryStats(
     return planCache->getMatchingStats(serializer, predicate);
 }
 
-bool MongoInterfaceStandalone::fieldsHaveSupportingUniqueIndex(
+bool CommonMongodProcessInterface::fieldsHaveSupportingUniqueIndex(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     const std::set<FieldPath>& fieldPaths) const {
@@ -655,7 +470,7 @@ bool MongoInterfaceStandalone::fieldsHaveSupportingUniqueIndex(
     return false;
 }
 
-BSONObj MongoInterfaceStandalone::_reportCurrentOpForClient(
+BSONObj CommonMongodProcessInterface::_reportCurrentOpForClient(
     OperationContext* opCtx,
     Client* client,
     CurrentOpTruncateMode truncateOps,
@@ -692,14 +507,13 @@ BSONObj MongoInterfaceStandalone::_reportCurrentOpForClient(
     return builder.obj();
 }
 
-void MongoInterfaceStandalone::_reportCurrentOpsForTransactionCoordinators(
+void CommonMongodProcessInterface::_reportCurrentOpsForTransactionCoordinators(
     OperationContext* opCtx, bool includeIdle, std::vector<BSONObj>* ops) const {
     reportCurrentOpsForTransactionCoordinators(opCtx, includeIdle, ops);
 }
 
-void MongoInterfaceStandalone::_reportCurrentOpsForIdleSessions(OperationContext* opCtx,
-                                                                CurrentOpUserMode userMode,
-                                                                std::vector<BSONObj>* ops) const {
+void CommonMongodProcessInterface::_reportCurrentOpsForIdleSessions(
+    OperationContext* opCtx, CurrentOpUserMode userMode, std::vector<BSONObj>* ops) const {
     auto sessionCatalog = SessionCatalog::get(opCtx);
 
     const bool authEnabled =
@@ -721,7 +535,7 @@ void MongoInterfaceStandalone::_reportCurrentOpsForIdleSessions(OperationContext
     });
 }
 
-std::unique_ptr<CollatorInterface> MongoInterfaceStandalone::_getCollectionDefaultCollator(
+std::unique_ptr<CollatorInterface> CommonMongodProcessInterface::_getCollectionDefaultCollator(
     OperationContext* opCtx, StringData dbName, UUID collectionUUID) {
     auto it = _collatorCache.find(collectionUUID);
     if (it == _collatorCache.end()) {
@@ -745,13 +559,13 @@ std::unique_ptr<CollatorInterface> MongoInterfaceStandalone::_getCollectionDefau
     return collator ? collator->clone() : nullptr;
 }
 
-std::unique_ptr<ResourceYielder> MongoInterfaceStandalone::getResourceYielder() const {
+std::unique_ptr<ResourceYielder> CommonMongodProcessInterface::getResourceYielder() const {
     return std::make_unique<MongoDResourceYielder>();
 }
 
 
 std::pair<std::set<FieldPath>, boost::optional<ChunkVersion>>
-MongoInterfaceStandalone::ensureFieldsUniqueOrResolveDocumentKey(
+CommonMongodProcessInterface::ensureFieldsUniqueOrResolveDocumentKey(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     boost::optional<std::vector<std::string>> fields,
     boost::optional<ChunkVersion> targetCollectionVersion,
@@ -779,4 +593,54 @@ MongoInterfaceStandalone::ensureFieldsUniqueOrResolveDocumentKey(
     return {fieldPaths, targetCollectionVersion};
 }
 
+write_ops::Insert CommonMongodProcessInterface::buildInsertOp(const NamespaceString& nss,
+                                                              std::vector<BSONObj>&& objs,
+                                                              bool bypassDocValidation) {
+    write_ops::Insert insertOp(nss);
+    insertOp.setDocuments(std::move(objs));
+    insertOp.setWriteCommandBase([&] {
+        write_ops::WriteCommandBase wcb;
+        wcb.setOrdered(false);
+        wcb.setBypassDocumentValidation(bypassDocValidation);
+        return wcb;
+    }());
+    return insertOp;
+}
+
+Update CommonMongodProcessInterface::buildUpdateOp(
+    const boost::intrusive_ptr<ExpressionContext>& expCtx,
+    const NamespaceString& nss,
+    BatchedObjects&& batch,
+    UpsertType upsert,
+    bool multi) {
+    Update updateOp(nss);
+    updateOp.setUpdates([&] {
+        std::vector<write_ops::UpdateOpEntry> updateEntries;
+        for (auto&& obj : batch) {
+            updateEntries.push_back([&] {
+                write_ops::UpdateOpEntry entry;
+                auto&& [q, u, c] = obj;
+                entry.setQ(std::move(q));
+                entry.setU(std::move(u));
+                entry.setC(std::move(c));
+                entry.setUpsert(upsert != UpsertType::kNone);
+                // TODO SERVER-44884: after branching for 4.5, remove the 'useNewUpsert' flag.
+                entry.setUpsertSupplied({{entry.getUpsert() && expCtx->useNewUpsert,
+                                          upsert == UpsertType::kInsertSuppliedDoc}});
+                entry.setMulti(multi);
+                return entry;
+            }());
+        }
+        return updateEntries;
+    }());
+    updateOp.setWriteCommandBase([&] {
+        write_ops::WriteCommandBase wcb;
+        wcb.setOrdered(false);
+        wcb.setBypassDocumentValidation(expCtx->bypassDocumentValidation);
+        return wcb;
+    }());
+    updateOp.setRuntimeConstants(expCtx->getRuntimeConstants());
+    return updateOp;
+}
+
 }  // namespace mongo
diff --git a/src/mongo/db/pipeline/process_interface_standalone.h b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.h
index a8f098ee556..f8058e18d89 100644
--- a/src/mongo/db/pipeline/process_interface_standalone.h
+++ b/src/mongo/db/pipeline/process_interface/common_mongod_process_interface.h
@@ -1,5 +1,5 @@
 /**
- *    Copyright (C) 2018-present MongoDB, Inc.
+ *    Copyright (C) 2020-present MongoDB, Inc.
  *
  *    This program is free software: you can redistribute it and/or modify
  *    it under the terms of the Server Side Public License, version 1,
@@ -34,8 +34,8 @@
 #include "mongo/db/ops/write_ops_exec.h"
 #include "mongo/db/ops/write_ops_gen.h"
 #include "mongo/db/pipeline/javascript_execution.h"
-#include "mongo/db/pipeline/mongo_process_common.h"
 #include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/common_process_interface.h"
 
 namespace mongo {
 
@@ -43,16 +43,14 @@ using write_ops::Insert;
 using write_ops::Update;
 
 /**
- * Class to provide access to mongod-specific implementations of methods required by some
- * document sources.
+ * Provides the implementations of interfaces that are shared across different types of mongod
+ * nodes.
  */
-class MongoInterfaceStandalone : public MongoProcessCommon {
+class CommonMongodProcessInterface : public CommonProcessInterface {
 public:
-    // static std::shared_ptr<MongoProcessInterface> create(OperationContext* opCtx);
+    CommonMongodProcessInterface(OperationContext* opCtx);
 
-    MongoInterfaceStandalone(OperationContext* opCtx);
-
-    virtual ~MongoInterfaceStandalone() = default;
+    virtual ~CommonMongodProcessInterface() = default;
 
     std::unique_ptr<TransactionHistoryIteratorBase> createTransactionHistoryIterator(
         repl::OpTime time) const final;
@@ -62,27 +60,12 @@ public:
      * sending request against nss based on this information.
      */
     bool isSharded(OperationContext* opCtx, const NamespaceString& nss) final;
-    Status insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                  const NamespaceString& ns,
-                  std::vector<BSONObj>&& objs,
-                  const WriteConcernOptions& wc,
-                  boost::optional<OID> targetEpoch) override;
-    StatusWith<UpdateResult> update(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                                    const NamespaceString& ns,
-                                    BatchedObjects&& batch,
-                                    const WriteConcernOptions& wc,
-                                    UpsertType upsert,
-                                    bool multi,
-                                    boost::optional<OID> targetEpoch) override;
 
     std::vector<Document> getIndexStats(OperationContext* opCtx,
                                         const NamespaceString& ns,
                                         StringData host,
                                         bool addShardName) final;
 
-    std::list<BSONObj> getIndexSpecs(OperationContext* opCtx,
-                                     const NamespaceString& ns,
-                                     bool includeBuildUUIDs);
     void appendLatencyStats(OperationContext* opCtx,
                             const NamespaceString& nss,
                             bool includeHistograms,
@@ -98,39 +81,14 @@ public:
                                 const NamespaceString& nss,
                                 BSONObjBuilder* builder) const final override;
     BSONObj getCollectionOptions(OperationContext* opCtx, const NamespaceString& nss) final;
-    void renameIfOptionsAndIndexesHaveNotChanged(OperationContext* opCtx,
-                                                 const BSONObj& renameCommandObj,
-                                                 const NamespaceString& targetNs,
-                                                 const BSONObj& originalCollectionOptions,
-                                                 const std::list<BSONObj>& originalIndexes);
-    void createCollection(OperationContext* opCtx,
-                          const std::string& dbName,
-                          const BSONObj& cmdObj);
-    void createIndexesOnEmptyCollection(OperationContext* opCtx,
-                                        const NamespaceString& ns,
-                                        const std::vector<BSONObj>& indexSpecs);
-    void dropCollection(OperationContext* opCtx, const NamespaceString& collection);
     std::unique_ptr<Pipeline, PipelineDeleter> makePipeline(
         const std::vector<BSONObj>& rawPipeline,
         const boost::intrusive_ptr<ExpressionContext>& expCtx,
         const MakePipelineOptions opts = MakePipelineOptions{}) final;
-    std::unique_ptr<Pipeline, PipelineDeleter> attachCursorSourceToPipeline(
-        const boost::intrusive_ptr<ExpressionContext>& expCtx,
-        Pipeline* pipeline,
-        bool allowTargetingShards = true) override;
     std::unique_ptr<Pipeline, PipelineDeleter> attachCursorSourceToPipelineForLocalRead(
-        const boost::intrusive_ptr<ExpressionContext>& expCtx, Pipeline* pipeline) override;
+        const boost::intrusive_ptr<ExpressionContext>& expCtx, Pipeline* pipeline) final;
     std::string getShardName(OperationContext* opCtx) const final;
 
-    std::unique_ptr<ShardFilterer> getShardFilterer(
-        const boost::intrusive_ptr<ExpressionContext>& expCtx) const override {
-        // We'll never do shard filtering on a standalone.
-        return nullptr;
-    }
-    std::pair<std::vector<FieldPath>, bool> collectDocumentKeyFieldsForHostedCollection(
-        OperationContext* opCtx, const NamespaceString&, UUID) const override;
-    std::vector<FieldPath> collectDocumentKeyFieldsActingAsRouter(
-        OperationContext* opCtx, const NamespaceString&) const override;
     boost::optional<Document> lookupSingleDocument(
         const boost::intrusive_ptr<ExpressionContext>& expCtx,
         const NamespaceString& nss,
@@ -155,38 +113,15 @@ public:
                                          const NamespaceString& nss,
                                          const std::set<FieldPath>& fieldPaths) const;
 
-    boost::optional<ChunkVersion> refreshAndGetCollectionVersion(
-        const boost::intrusive_ptr<ExpressionContext>& expCtx,
-        const NamespaceString& nss) const final {
-        return boost::none;  // Nothing is sharded here.
-    }
-    virtual void checkRoutingInfoEpochOrThrow(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                                              const NamespaceString& nss,
-                                              ChunkVersion targetCollectionVersion) const override {
-        uasserted(51020, "unexpected request to consult sharding catalog on non-shardsvr");
-    }
-
-    std::unique_ptr<ResourceYielder> getResourceYielder() const override;
+    std::unique_ptr<ResourceYielder> getResourceYielder() const final;
 
     std::pair<std::set<FieldPath>, boost::optional<ChunkVersion>>
     ensureFieldsUniqueOrResolveDocumentKey(const boost::intrusive_ptr<ExpressionContext>& expCtx,
                                            boost::optional<std::vector<std::string>> fields,
                                            boost::optional<ChunkVersion> targetCollectionVersion,
-                                           const NamespaceString& outputNs) const override;
+                                           const NamespaceString& outputNs) const final;
 
 protected:
-    BSONObj _reportCurrentOpForClient(OperationContext* opCtx,
-                                      Client* client,
-                                      CurrentOpTruncateMode truncateOps,
-                                      CurrentOpBacktraceMode backtraceMode) const final;
-
-    void _reportCurrentOpsForIdleSessions(OperationContext* opCtx,
-                                          CurrentOpUserMode userMode,
-                                          std::vector<BSONObj>* ops) const final;
-
-    void _reportCurrentOpsForTransactionCoordinators(OperationContext* opCtx,
-                                                     bool includeIdle,
-                                                     std::vector<BSONObj>* ops) const final;
     /**
      * Builds an ordered insert op on namespace 'nss' and documents to be written 'objs'.
      */
@@ -203,6 +138,19 @@ protected:
                          UpsertType upsert,
                          bool multi);
 
+    BSONObj _reportCurrentOpForClient(OperationContext* opCtx,
+                                      Client* client,
+                                      CurrentOpTruncateMode truncateOps,
+                                      CurrentOpBacktraceMode backtraceMode) const final;
+
+    void _reportCurrentOpsForIdleSessions(OperationContext* opCtx,
+                                          CurrentOpUserMode userMode,
+                                          std::vector<BSONObj>* ops) const final;
+
+    void _reportCurrentOpsForTransactionCoordinators(OperationContext* opCtx,
+                                                     bool includeIdle,
+                                                     std::vector<BSONObj>* ops) const final;
+
 private:
     /**
      * Looks up the collection default collator for the collection given by 'collectionUUID'. A
diff --git a/src/mongo/db/pipeline/mongo_process_common.cpp b/src/mongo/db/pipeline/process_interface/common_process_interface.cpp
index bb5466b9f8f..9d5acc0bb10 100644
--- a/src/mongo/db/pipeline/mongo_process_common.cpp
+++ b/src/mongo/db/pipeline/process_interface/common_process_interface.cpp
@@ -31,7 +31,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/pipeline/mongo_process_common.h"
+#include "mongo/db/pipeline/process_interface/common_process_interface.h"
 
 #include "mongo/bson/mutable/document.h"
 #include "mongo/db/auth/authorization_manager.h"
@@ -51,7 +51,7 @@
 
 namespace mongo {
 
-std::vector<BSONObj> MongoProcessCommon::getCurrentOps(
+std::vector<BSONObj> CommonProcessInterface::getCurrentOps(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     CurrentOpConnectionsMode connMode,
     CurrentOpSessionsMode sessionMode,
@@ -129,7 +129,7 @@ std::vector<BSONObj> MongoProcessCommon::getCurrentOps(
     return ops;
 }
 
-std::vector<FieldPath> MongoProcessCommon::collectDocumentKeyFieldsActingAsRouter(
+std::vector<FieldPath> CommonProcessInterface::collectDocumentKeyFieldsActingAsRouter(
     OperationContext* opCtx, const NamespaceString& nss) const {
     if (auto chunkManager =
             uassertStatusOK(Grid::get(opCtx)->catalogCache()->getCollectionRoutingInfo(opCtx, nss))
@@ -141,8 +141,8 @@ std::vector<FieldPath> MongoProcessCommon::collectDocumentKeyFieldsActingAsRoute
     return {"_id"};
 }
 
-bool MongoProcessCommon::keyPatternNamesExactPaths(const BSONObj& keyPattern,
-                                                   const std::set<FieldPath>& uniqueKeyPaths) {
+bool CommonProcessInterface::keyPatternNamesExactPaths(
+    const BSONObj& keyPattern, const std::set<FieldPath>& uniqueKeyPaths) {
     size_t nFieldsMatched = 0;
     for (auto&& elem : keyPattern) {
         if (!elem.isNumber()) {
@@ -156,7 +156,7 @@ bool MongoProcessCommon::keyPatternNamesExactPaths(const BSONObj& keyPattern,
     return nFieldsMatched == uniqueKeyPaths.size();
 }
 
-boost::optional<ChunkVersion> MongoProcessCommon::refreshAndGetCollectionVersion(
+boost::optional<ChunkVersion> CommonProcessInterface::refreshAndGetCollectionVersion(
     const boost::intrusive_ptr<ExpressionContext>& expCtx, const NamespaceString& nss) const {
     const bool forceRefreshFromThisThread = false;
     auto routingInfo = uassertStatusOK(
@@ -169,7 +169,7 @@ boost::optional<ChunkVersion> MongoProcessCommon::refreshAndGetCollectionVersion
     return boost::none;
 }
 
-std::vector<FieldPath> MongoProcessCommon::_shardKeyToDocumentKeyFields(
+std::vector<FieldPath> CommonProcessInterface::_shardKeyToDocumentKeyFields(
     const std::vector<std::unique_ptr<FieldRef>>& keyPatternFields) const {
     std::vector<FieldPath> result;
     bool gotId = false;
@@ -183,7 +183,7 @@ std::vector<FieldPath> MongoProcessCommon::_shardKeyToDocumentKeyFields(
     return result;
 }
 
-std::set<FieldPath> MongoProcessCommon::_convertToFieldPaths(
+std::set<FieldPath> CommonProcessInterface::_convertToFieldPaths(
     const std::vector<std::string>& fields) const {
     std::set<FieldPath> fieldPaths;
 
@@ -196,7 +196,7 @@ std::set<FieldPath> MongoProcessCommon::_convertToFieldPaths(
     return fieldPaths;
 }
 
-std::string MongoProcessCommon::getHostAndPort(OperationContext* opCtx) const {
+std::string CommonProcessInterface::getHostAndPort(OperationContext* opCtx) const {
     return getHostNameCachedAndPort();
 }
 
diff --git a/src/mongo/db/pipeline/mongo_process_common.h b/src/mongo/db/pipeline/process_interface/common_process_interface.h
index 0b6cd75c764..7f68f8d201f 100644
--- a/src/mongo/db/pipeline/mongo_process_common.h
+++ b/src/mongo/db/pipeline/process_interface/common_process_interface.h
@@ -32,17 +32,17 @@
 #include <vector>
 
 #include "mongo/bson/bsonobj.h"
-#include "mongo/db/pipeline/mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongo_process_interface.h"
 
 namespace mongo {
 
 /**
- * MongoProcessCommon provides base implementations of any MongoProcessInterface methods whose code
- * is largely identical on mongoD and mongoS.
+ * CommonProcessInterface provides base implementations of any MongoProcessInterface methods
+ * whose code is largely identical on mongoD and mongoS.
  */
-class MongoProcessCommon : public MongoProcessInterface {
+class CommonProcessInterface : public MongoProcessInterface {
 public:
-    virtual ~MongoProcessCommon() = default;
+    virtual ~CommonProcessInterface() = default;
 
     /**
      * Returns true if the field names of 'keyPattern' are exactly those in 'uniqueKeyPaths', and
@@ -80,7 +80,7 @@ protected:
     /**
      * Returns a BSONObj representing a report of the operation which is currently being
      * executed by the supplied client. This method is called by the getCurrentOps method of
-     * MongoProcessCommon to delegate to the mongoS- or mongoD- specific implementation.
+     * CommonProcessInterface to delegate to the mongoS- or mongoD- specific implementation.
      */
     virtual BSONObj _reportCurrentOpForClient(OperationContext* opCtx,
                                               Client* client,
diff --git a/src/mongo/db/pipeline/mongo_process_interface.cpp b/src/mongo/db/pipeline/process_interface/mongo_process_interface.cpp
index 69cb07aeb87..46101c78629 100644
--- a/src/mongo/db/pipeline/mongo_process_interface.cpp
+++ b/src/mongo/db/pipeline/process_interface/mongo_process_interface.cpp
@@ -29,7 +29,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongo_process_interface.h"
 
 #include "mongo/base/shim.h"
 
diff --git a/src/mongo/db/pipeline/mongo_process_interface.h b/src/mongo/db/pipeline/process_interface/mongo_process_interface.h
index c4d5267f452..c4d5267f452 100644
--- a/src/mongo/db/pipeline/mongo_process_interface.h
+++ b/src/mongo/db/pipeline/process_interface/mongo_process_interface.h
diff --git a/src/mongo/db/pipeline/process_interface_factory_mongod.cpp b/src/mongo/db/pipeline/process_interface/mongod_process_interface_factory.cpp
index d8c3de62131..3845cfcd3f2 100644
--- a/src/mongo/db/pipeline/process_interface_factory_mongod.cpp
+++ b/src/mongo/db/pipeline/process_interface/mongod_process_interface_factory.cpp
@@ -30,15 +30,18 @@
 #include "mongo/platform/basic.h"
 
 #include "mongo/base/shim.h"
-#include "mongo/db/pipeline/process_interface_shardsvr.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
+#include "mongo/db/pipeline/process_interface/shardsvr_process_interface.h"
 #include "mongo/db/s/sharding_state.h"
 
 namespace mongo {
 namespace {
 
 std::shared_ptr<MongoProcessInterface> MongoProcessInterfaceCreateImpl(OperationContext* opCtx) {
-    return ShardingState::get(opCtx)->enabled() ? std::make_shared<MongoInterfaceShardServer>(opCtx)
-                                                : std::make_shared<MongoInterfaceStandalone>(opCtx);
+    if (ShardingState::get(opCtx)->enabled()) {
+        return std::make_shared<ShardServerProcessInterface>(opCtx);
+    }
+    return std::make_shared<NonShardServerProcessInterface>(opCtx);
 }
 
 auto mongoProcessInterfaceCreateRegistration = MONGO_WEAK_FUNCTION_REGISTRATION(
diff --git a/src/mongo/db/pipeline/mongos_process_interface.cpp b/src/mongo/db/pipeline/process_interface/mongos_process_interface.cpp
index 29dc6f070db..938006f7f8a 100644
--- a/src/mongo/db/pipeline/mongos_process_interface.cpp
+++ b/src/mongo/db/pipeline/process_interface/mongos_process_interface.cpp
@@ -29,7 +29,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/pipeline/mongos_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongos_process_interface.h"
 
 #include "mongo/db/auth/authorization_session.h"
 #include "mongo/db/catalog/collection_catalog.h"
@@ -93,14 +93,14 @@ bool supportsUniqueKey(const boost::intrusive_ptr<ExpressionContext>& expCtx,
     auto isIdIndex = index[IndexDescriptor::kIndexNameFieldName].String() == "_id_";
     return (isIdIndex || index.getBoolField(IndexDescriptor::kUniqueFieldName)) &&
         !index.hasField(IndexDescriptor::kPartialFilterExprFieldName) &&
-        MongoProcessCommon::keyPatternNamesExactPaths(
+        CommonProcessInterface::keyPatternNamesExactPaths(
                index.getObjectField(IndexDescriptor::kKeyPatternFieldName), uniqueKeyPaths) &&
         CollatorInterface::collatorsMatch(collation.get(), expCtx->getCollator());
 }
 
 }  // namespace
 
-std::unique_ptr<Pipeline, PipelineDeleter> MongoSInterface::makePipeline(
+std::unique_ptr<Pipeline, PipelineDeleter> MongosProcessInterface::makePipeline(
     const std::vector<BSONObj>& rawPipeline,
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const MakePipelineOptions pipelineOptions) {
@@ -119,7 +119,7 @@ std::unique_ptr<Pipeline, PipelineDeleter> MongoSInterface::makePipeline(
     return pipeline;
 }
 
-std::unique_ptr<Pipeline, PipelineDeleter> MongoSInterface::attachCursorSourceToPipeline(
+std::unique_ptr<Pipeline, PipelineDeleter> MongosProcessInterface::attachCursorSourceToPipeline(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     Pipeline* ownedPipeline,
     bool allowTargetingShards) {
@@ -127,7 +127,7 @@ std::unique_ptr<Pipeline, PipelineDeleter> MongoSInterface::attachCursorSourceTo
     return sharded_agg_helpers::targetShardsAndAddMergeCursors(expCtx, ownedPipeline);
 }
 
-boost::optional<Document> MongoSInterface::lookupSingleDocument(
+boost::optional<Document> MongosProcessInterface::lookupSingleDocument(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     UUID collectionUUID,
@@ -241,10 +241,11 @@ boost::optional<Document> MongoSInterface::lookupSingleDocument(
     return (!finalBatch.empty() ? Document(finalBatch.front()) : boost::optional<Document>{});
 }
 
-BSONObj MongoSInterface::_reportCurrentOpForClient(OperationContext* opCtx,
-                                                   Client* client,
-                                                   CurrentOpTruncateMode truncateOps,
-                                                   CurrentOpBacktraceMode backtraceMode) const {
+BSONObj MongosProcessInterface::_reportCurrentOpForClient(
+    OperationContext* opCtx,
+    Client* client,
+    CurrentOpTruncateMode truncateOps,
+    CurrentOpBacktraceMode backtraceMode) const {
     BSONObjBuilder builder;
 
     CurOp::reportCurrentOpForClient(opCtx,
@@ -264,9 +265,9 @@ BSONObj MongoSInterface::_reportCurrentOpForClient(OperationContext* opCtx,
     return builder.obj();
 }
 
-void MongoSInterface::_reportCurrentOpsForIdleSessions(OperationContext* opCtx,
-                                                       CurrentOpUserMode userMode,
-                                                       std::vector<BSONObj>* ops) const {
+void MongosProcessInterface::_reportCurrentOpsForIdleSessions(OperationContext* opCtx,
+                                                              CurrentOpUserMode userMode,
+                                                              std::vector<BSONObj>* ops) const {
     auto sessionCatalog = SessionCatalog::get(opCtx);
 
     const bool authEnabled =
@@ -291,10 +292,10 @@ void MongoSInterface::_reportCurrentOpsForIdleSessions(OperationContext* opCtx,
     });
 }
 
-void MongoSInterface::_reportCurrentOpsForTransactionCoordinators(
+void MongosProcessInterface::_reportCurrentOpsForTransactionCoordinators(
     OperationContext* opCtx, bool includeIdle, std::vector<BSONObj>* ops) const {};
 
-std::vector<GenericCursor> MongoSInterface::getIdleCursors(
+std::vector<GenericCursor> MongosProcessInterface::getIdleCursors(
     const intrusive_ptr<ExpressionContext>& expCtx, CurrentOpUserMode userMode) const {
     invariant(hasGlobalServiceContext());
     auto cursorManager = Grid::get(expCtx->opCtx->getServiceContext())->getCursorManager();
@@ -302,12 +303,12 @@ std::vector<GenericCursor> MongoSInterface::getIdleCursors(
     return cursorManager->getIdleCursors(expCtx->opCtx, userMode);
 }
 
-bool MongoSInterface::isSharded(OperationContext* opCtx, const NamespaceString& nss) {
+bool MongosProcessInterface::isSharded(OperationContext* opCtx, const NamespaceString& nss) {
     auto routingInfo = Grid::get(opCtx)->catalogCache()->getCollectionRoutingInfo(opCtx, nss);
     return routingInfo.isOK() && routingInfo.getValue().cm();
 }
 
-bool MongoSInterface::fieldsHaveSupportingUniqueIndex(
+bool MongosProcessInterface::fieldsHaveSupportingUniqueIndex(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     const std::set<FieldPath>& fieldPaths) const {
@@ -336,7 +337,7 @@ bool MongoSInterface::fieldsHaveSupportingUniqueIndex(
 }
 
 std::pair<std::set<FieldPath>, boost::optional<ChunkVersion>>
-MongoSInterface::ensureFieldsUniqueOrResolveDocumentKey(
+MongosProcessInterface::ensureFieldsUniqueOrResolveDocumentKey(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     boost::optional<std::vector<std::string>> fields,
     boost::optional<ChunkVersion> targetCollectionVersion,
diff --git a/src/mongo/db/pipeline/mongos_process_interface.h b/src/mongo/db/pipeline/process_interface/mongos_process_interface.h
index 8d93190cbcb..36abd00c6da 100644
--- a/src/mongo/db/pipeline/mongos_process_interface.h
+++ b/src/mongo/db/pipeline/process_interface/mongos_process_interface.h
@@ -30,8 +30,8 @@
 #pragma once
 
 #include "mongo/db/exec/shard_filterer.h"
-#include "mongo/db/pipeline/mongo_process_common.h"
 #include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/common_process_interface.h"
 
 namespace mongo {
 
@@ -39,11 +39,11 @@ namespace mongo {
  * Class to provide access to mongos-specific implementations of methods required by some
  * document sources.
  */
-class MongoSInterface : public MongoProcessCommon {
+class MongosProcessInterface : public CommonProcessInterface {
 public:
-    MongoSInterface() = default;
+    MongosProcessInterface() = default;
 
-    virtual ~MongoSInterface() = default;
+    virtual ~MongosProcessInterface() = default;
 
     boost::optional<Document> lookupSingleDocument(
         const boost::intrusive_ptr<ExpressionContext>& expCtx,
diff --git a/src/mongo/db/pipeline/mongos_process_interface_test.cpp b/src/mongo/db/pipeline/process_interface/mongos_process_interface_test.cpp
index 91d79185481..63d69d93eab 100644
--- a/src/mongo/db/pipeline/mongos_process_interface_test.cpp
+++ b/src/mongo/db/pipeline/process_interface/mongos_process_interface_test.cpp
@@ -30,15 +30,15 @@
 #include "mongo/platform/basic.h"
 
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
-#include "mongo/db/pipeline/mongos_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongos_process_interface.h"
 #include "mongo/unittest/unittest.h"
 
 namespace mongo {
 namespace {
 
-class MongoProcessInterfaceForTest : public MongoSInterface {
+class MongosProcessInterfaceForTest : public MongosProcessInterface {
 public:
-    using MongoSInterface::MongoSInterface;
+    using MongosProcessInterface::MongosProcessInterface;
 
     bool fieldsHaveSupportingUniqueIndex(const boost::intrusive_ptr<ExpressionContext>& expCtx,
                                          const NamespaceString& nss,
@@ -49,18 +49,18 @@ public:
     bool hasSupportingIndexForFields{true};
 };
 
-class MongoSInterfaceTest : public AggregationContextFixture {
+class MongosProcessInterfaceTest : public AggregationContextFixture {
 public:
-    MongoSInterfaceTest() {
+    MongosProcessInterfaceTest() {
         getExpCtx()->inMongos = true;
     }
 
     auto makeProcessInterface() {
-        return std::make_unique<MongoProcessInterfaceForTest>();
+        return std::make_unique<MongosProcessInterfaceForTest>();
     }
 };
 
-TEST_F(MongoSInterfaceTest, FailsToEnsureFieldsUniqueIfTargetCollectionVersionIsSpecified) {
+TEST_F(MongosProcessInterfaceTest, FailsToEnsureFieldsUniqueIfTargetCollectionVersionIsSpecified) {
     auto expCtx = getExpCtx();
     auto targetCollectionVersion = boost::make_optional(ChunkVersion(0, 0, OID::gen()));
     auto processInterface = makeProcessInterface();
@@ -71,7 +71,7 @@ TEST_F(MongoSInterfaceTest, FailsToEnsureFieldsUniqueIfTargetCollectionVersionIs
                        51179);
 }
 
-TEST_F(MongoSInterfaceTest, FailsToEnsureFieldsUniqueIfNotSupportedByIndex) {
+TEST_F(MongosProcessInterfaceTest, FailsToEnsureFieldsUniqueIfNotSupportedByIndex) {
     auto expCtx = getExpCtx();
     auto targetCollectionVersion = boost::none;
     auto processInterface = makeProcessInterface();
diff --git a/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.cpp b/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.cpp
new file mode 100644
index 00000000000..5b2f64e4802
--- /dev/null
+++ b/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.cpp
@@ -0,0 +1,171 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
+
+#include "mongo/db/catalog/create_collection.h"
+#include "mongo/db/catalog/drop_collection.h"
+#include "mongo/db/catalog/list_indexes.h"
+#include "mongo/db/catalog/rename_collection.h"
+#include "mongo/db/concurrency/d_concurrency.h"
+#include "mongo/db/concurrency/write_conflict_exception.h"
+#include "mongo/db/db_raii.h"
+#include "mongo/db/index_builds_coordinator.h"
+
+namespace mongo {
+
+Status NonShardServerProcessInterface::insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
+                                              const NamespaceString& ns,
+                                              std::vector<BSONObj>&& objs,
+                                              const WriteConcernOptions& wc,
+                                              boost::optional<OID> targetEpoch) {
+    auto writeResults = performInserts(
+        expCtx->opCtx, buildInsertOp(ns, std::move(objs), expCtx->bypassDocumentValidation));
+
+    // Need to check each result in the batch since the writes are unordered.
+    for (const auto& result : writeResults.results) {
+        if (result.getStatus() != Status::OK()) {
+            return result.getStatus();
+        }
+    }
+    return Status::OK();
+}
+
+StatusWith<MongoProcessInterface::UpdateResult> NonShardServerProcessInterface::update(
+    const boost::intrusive_ptr<ExpressionContext>& expCtx,
+    const NamespaceString& ns,
+    BatchedObjects&& batch,
+    const WriteConcernOptions& wc,
+    UpsertType upsert,
+    bool multi,
+    boost::optional<OID> targetEpoch) {
+    auto writeResults =
+        performUpdates(expCtx->opCtx, buildUpdateOp(expCtx, ns, std::move(batch), upsert, multi));
+
+    // Need to check each result in the batch since the writes are unordered.
+    UpdateResult updateResult;
+    for (const auto& result : writeResults.results) {
+        if (result.getStatus() != Status::OK()) {
+            return result.getStatus();
+        }
+
+        updateResult.nMatched += result.getValue().getN();
+        updateResult.nModified += result.getValue().getNModified();
+    }
+    return updateResult;
+}
+
+std::list<BSONObj> NonShardServerProcessInterface::getIndexSpecs(OperationContext* opCtx,
+                                                                 const NamespaceString& ns,
+                                                                 bool includeBuildUUIDs) {
+    return listIndexesEmptyListIfMissing(opCtx, ns, includeBuildUUIDs);
+}
+
+void NonShardServerProcessInterface::createIndexesOnEmptyCollection(
+    OperationContext* opCtx, const NamespaceString& ns, const std::vector<BSONObj>& indexSpecs) {
+    AutoGetCollection autoColl(opCtx, ns, MODE_X);
+    writeConflictRetry(
+        opCtx, "CommonMongodProcessInterface::createIndexesOnEmptyCollection", ns.ns(), [&] {
+            auto collection = autoColl.getCollection();
+            invariant(collection,
+                      str::stream() << "Failed to create indexes for aggregation because "
+                                       "collection does not exist: "
+                                    << ns << ": " << BSON("indexes" << indexSpecs));
+
+            invariant(0U == collection->numRecords(opCtx),
+                      str::stream() << "Expected empty collection for index creation: " << ns
+                                    << ": numRecords: " << collection->numRecords(opCtx) << ": "
+                                    << BSON("indexes" << indexSpecs));
+
+            // Secondary index builds do not filter existing indexes so we have to do this on the
+            // primary.
+            auto removeIndexBuildsToo = false;
+            auto filteredIndexes = collection->getIndexCatalog()->removeExistingIndexes(
+                opCtx, indexSpecs, removeIndexBuildsToo);
+            if (filteredIndexes.empty()) {
+                return;
+            }
+
+            WriteUnitOfWork wuow(opCtx);
+            IndexBuildsCoordinator::get(opCtx)->createIndexesOnEmptyCollection(
+                opCtx, collection->uuid(), filteredIndexes, false  // fromMigrate
+            );
+            wuow.commit();
+        });
+}
+void NonShardServerProcessInterface::renameIfOptionsAndIndexesHaveNotChanged(
+    OperationContext* opCtx,
+    const BSONObj& renameCommandObj,
+    const NamespaceString& targetNs,
+    const BSONObj& originalCollectionOptions,
+    const std::list<BSONObj>& originalIndexes) {
+    NamespaceString sourceNs = NamespaceString(renameCommandObj["renameCollection"].String());
+    doLocalRenameIfOptionsAndIndexesHaveNotChanged(opCtx,
+                                                   sourceNs,
+                                                   targetNs,
+                                                   renameCommandObj["dropTarget"].trueValue(),
+                                                   renameCommandObj["stayTemp"].trueValue(),
+                                                   originalIndexes,
+                                                   originalCollectionOptions);
+}
+
+void NonShardServerProcessInterface::createCollection(OperationContext* opCtx,
+                                                      const std::string& dbName,
+                                                      const BSONObj& cmdObj) {
+    uassertStatusOK(mongo::createCollection(opCtx, dbName, cmdObj));
+}
+
+void NonShardServerProcessInterface::dropCollection(OperationContext* opCtx,
+                                                    const NamespaceString& ns) {
+    BSONObjBuilder result;
+    uassertStatusOK(mongo::dropCollection(
+        opCtx, ns, result, {}, DropCollectionSystemCollectionMode::kDisallowSystemCollectionDrops));
+}
+
+std::unique_ptr<Pipeline, PipelineDeleter>
+NonShardServerProcessInterface::attachCursorSourceToPipeline(
+    const boost::intrusive_ptr<ExpressionContext>& expCtx,
+    Pipeline* ownedPipeline,
+    bool allowTargetingShards) {
+    return attachCursorSourceToPipelineForLocalRead(expCtx, ownedPipeline);
+}
+
+std::pair<std::vector<FieldPath>, bool>
+NonShardServerProcessInterface::collectDocumentKeyFieldsForHostedCollection(
+    OperationContext* opCtx, const NamespaceString& nss, UUID uuid) const {
+    return {{"_id"}, false};  // Nothing is sharded.
+}
+
+std::vector<FieldPath> NonShardServerProcessInterface::collectDocumentKeyFieldsActingAsRouter(
+    OperationContext* opCtx, const NamespaceString& nss) const {
+    return {"_id"};  // Nothing is sharded.
+}
+}  // namespace mongo
diff --git a/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h b/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h
new file mode 100644
index 00000000000..cd58220c9f0
--- /dev/null
+++ b/src/mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h
@@ -0,0 +1,106 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/db/client.h"
+#include "mongo/db/exec/shard_filterer.h"
+#include "mongo/db/ops/write_ops_gen.h"
+#include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/common_mongod_process_interface.h"
+
+namespace mongo {
+
+/**
+ * Class to provide access to mongod-specific implementations of methods required by some
+ * document sources.
+ */
+class NonShardServerProcessInterface : public CommonMongodProcessInterface {
+public:
+    using CommonMongodProcessInterface::CommonMongodProcessInterface;
+
+    virtual ~NonShardServerProcessInterface() = default;
+
+    Status insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
+                  const NamespaceString& ns,
+                  std::vector<BSONObj>&& objs,
+                  const WriteConcernOptions& wc,
+                  boost::optional<OID> targetEpoch) override;
+    StatusWith<UpdateResult> update(const boost::intrusive_ptr<ExpressionContext>& expCtx,
+                                    const NamespaceString& ns,
+                                    BatchedObjects&& batch,
+                                    const WriteConcernOptions& wc,
+                                    UpsertType upsert,
+                                    bool multi,
+                                    boost::optional<OID> targetEpoch) override;
+
+    std::list<BSONObj> getIndexSpecs(OperationContext* opCtx,
+                                     const NamespaceString& ns,
+                                     bool includeBuildUUIDs);
+    void renameIfOptionsAndIndexesHaveNotChanged(OperationContext* opCtx,
+                                                 const BSONObj& renameCommandObj,
+                                                 const NamespaceString& targetNs,
+                                                 const BSONObj& originalCollectionOptions,
+                                                 const std::list<BSONObj>& originalIndexes);
+    void createCollection(OperationContext* opCtx,
+                          const std::string& dbName,
+                          const BSONObj& cmdObj);
+    void dropCollection(OperationContext* opCtx, const NamespaceString& collection);
+    void createIndexesOnEmptyCollection(OperationContext* opCtx,
+                                        const NamespaceString& ns,
+                                        const std::vector<BSONObj>& indexSpecs);
+    std::unique_ptr<Pipeline, PipelineDeleter> attachCursorSourceToPipeline(
+        const boost::intrusive_ptr<ExpressionContext>& expCtx,
+        Pipeline* pipeline,
+        bool allowTargetingShards) override;
+    std::unique_ptr<ShardFilterer> getShardFilterer(
+        const boost::intrusive_ptr<ExpressionContext>& expCtx) const override {
+        // We'll never do shard filtering on a standalone.
+        return nullptr;
+    }
+
+    boost::optional<ChunkVersion> refreshAndGetCollectionVersion(
+        const boost::intrusive_ptr<ExpressionContext>& expCtx,
+        const NamespaceString& nss) const final {
+        return boost::none;  // Nothing is sharded here.
+    }
+
+    virtual void checkRoutingInfoEpochOrThrow(const boost::intrusive_ptr<ExpressionContext>& expCtx,
+                                              const NamespaceString& nss,
+                                              ChunkVersion targetCollectionVersion) const override {
+        uasserted(51020, "unexpected request to consult sharding catalog on non-shardsvr");
+    }
+    std::pair<std::vector<FieldPath>, bool> collectDocumentKeyFieldsForHostedCollection(
+        OperationContext* opCtx, const NamespaceString&, UUID) const final;
+
+    std::vector<FieldPath> collectDocumentKeyFieldsActingAsRouter(
+        OperationContext*, const NamespaceString&) const final;
+};
+
+}  // namespace mongo
diff --git a/src/mongo/db/pipeline/process_interface_shardsvr.cpp b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface.cpp
index 843d37019b5..dcd5179def4 100644
--- a/src/mongo/db/pipeline/process_interface_shardsvr.cpp
+++ b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface.cpp
@@ -31,16 +31,9 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/pipeline/process_interface_shardsvr.h"
-
-#include "mongo/db/auth/authorization_session.h"
-#include "mongo/db/catalog/collection.h"
-#include "mongo/db/catalog/collection_catalog.h"
-#include "mongo/db/catalog/database_holder.h"
-#include "mongo/db/catalog/document_validation.h"
-#include "mongo/db/commands.h"
+#include "mongo/db/pipeline/process_interface/shardsvr_process_interface.h"
+
 #include "mongo/db/concurrency/d_concurrency.h"
-#include "mongo/db/curop.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/exec/shard_filterer_impl.h"
 #include "mongo/db/ops/write_ops_exec.h"
@@ -80,7 +73,7 @@ void attachWriteConcern(BatchedCommandRequest* request, const WriteConcernOption
 
 }  // namespace
 
-void MongoInterfaceShardServer::checkRoutingInfoEpochOrThrow(
+void ShardServerProcessInterface::checkRoutingInfoEpochOrThrow(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     ChunkVersion targetCollectionVersion) const {
@@ -91,9 +84,9 @@ void MongoInterfaceShardServer::checkRoutingInfoEpochOrThrow(
 }
 
 std::pair<std::vector<FieldPath>, bool>
-MongoInterfaceShardServer::collectDocumentKeyFieldsForHostedCollection(OperationContext* opCtx,
-                                                                       const NamespaceString& nss,
-                                                                       UUID uuid) const {
+ShardServerProcessInterface::collectDocumentKeyFieldsForHostedCollection(OperationContext* opCtx,
+                                                                         const NamespaceString& nss,
+                                                                         UUID uuid) const {
     invariant(serverGlobalParams.clusterRole == ClusterRole::ShardServer);
 
     const auto metadata = [opCtx, &nss]() -> ScopedCollectionMetadata {
@@ -115,11 +108,11 @@ MongoInterfaceShardServer::collectDocumentKeyFieldsForHostedCollection(Operation
     return {_shardKeyToDocumentKeyFields(metadata->getKeyPatternFields()), true};
 }
 
-Status MongoInterfaceShardServer::insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                                         const NamespaceString& ns,
-                                         std::vector<BSONObj>&& objs,
-                                         const WriteConcernOptions& wc,
-                                         boost::optional<OID> targetEpoch) {
+Status ShardServerProcessInterface::insert(const boost::intrusive_ptr<ExpressionContext>& expCtx,
+                                           const NamespaceString& ns,
+                                           std::vector<BSONObj>&& objs,
+                                           const WriteConcernOptions& wc,
+                                           boost::optional<OID> targetEpoch) {
     BatchedCommandResponse response;
     BatchWriteExecStats stats;
 
@@ -134,7 +127,7 @@ Status MongoInterfaceShardServer::insert(const boost::intrusive_ptr<ExpressionCo
     return response.toStatus();
 }
 
-StatusWith<MongoProcessInterface::UpdateResult> MongoInterfaceShardServer::update(
+StatusWith<MongoProcessInterface::UpdateResult> ShardServerProcessInterface::update(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& ns,
     BatchedObjects&& batch,
@@ -158,7 +151,7 @@ StatusWith<MongoProcessInterface::UpdateResult> MongoInterfaceShardServer::updat
     return {{response.getN(), response.getNModified()}};
 }
 
-unique_ptr<Pipeline, PipelineDeleter> MongoInterfaceShardServer::attachCursorSourceToPipeline(
+unique_ptr<Pipeline, PipelineDeleter> ShardServerProcessInterface::attachCursorSourceToPipeline(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     Pipeline* ownedPipeline,
     bool allowTargetingShards) {
@@ -175,7 +168,7 @@ unique_ptr<Pipeline, PipelineDeleter> MongoInterfaceShardServer::attachCursorSou
     return sharded_agg_helpers::targetShardsAndAddMergeCursors(expCtx, pipeline.release());
 }
 
-std::unique_ptr<ShardFilterer> MongoInterfaceShardServer::getShardFilterer(
+std::unique_ptr<ShardFilterer> ShardServerProcessInterface::getShardFilterer(
     const boost::intrusive_ptr<ExpressionContext>& expCtx) const {
     const bool aggNsIsCollection = expCtx->uuid != boost::none;
     auto collectionFilter = CollectionShardingState::get(expCtx->opCtx, expCtx->ns)
@@ -183,7 +176,7 @@ std::unique_ptr<ShardFilterer> MongoInterfaceShardServer::getShardFilterer(
     return std::make_unique<ShardFiltererImpl>(std::move(collectionFilter));
 }
 
-void MongoInterfaceShardServer::renameIfOptionsAndIndexesHaveNotChanged(
+void ShardServerProcessInterface::renameIfOptionsAndIndexesHaveNotChanged(
     OperationContext* opCtx,
     const BSONObj& renameCommandObj,
     const NamespaceString& destinationNs,
@@ -222,9 +215,9 @@ void MongoInterfaceShardServer::renameIfOptionsAndIndexesHaveNotChanged(
                                str::stream() << "failed while running command " << newCmdObj);
 }
 
-std::list<BSONObj> MongoInterfaceShardServer::getIndexSpecs(OperationContext* opCtx,
-                                                            const NamespaceString& ns,
-                                                            bool includeBuildUUIDs) {
+std::list<BSONObj> ShardServerProcessInterface::getIndexSpecs(OperationContext* opCtx,
+                                                              const NamespaceString& ns,
+                                                              bool includeBuildUUIDs) {
     auto cachedDbInfo =
         uassertStatusOK(Grid::get(opCtx)->catalogCache()->getDatabase(opCtx, ns.db()));
     auto shard = uassertStatusOK(
@@ -243,9 +236,9 @@ std::list<BSONObj> MongoInterfaceShardServer::getIndexSpecs(OperationContext* op
     }
     return std::list<BSONObj>(indexes.docs.begin(), indexes.docs.end());
 }
-void MongoInterfaceShardServer::createCollection(OperationContext* opCtx,
-                                                 const std::string& dbName,
-                                                 const BSONObj& cmdObj) {
+void ShardServerProcessInterface::createCollection(OperationContext* opCtx,
+                                                   const std::string& dbName,
+                                                   const BSONObj& cmdObj) {
     auto cachedDbInfo =
         uassertStatusOK(Grid::get(opCtx)->catalogCache()->getDatabase(opCtx, dbName));
     BSONObj finalCmdObj = cmdObj;
@@ -271,7 +264,7 @@ void MongoInterfaceShardServer::createCollection(OperationContext* opCtx,
                                    << "write concern failed while running command " << finalCmdObj);
 }
 
-void MongoInterfaceShardServer::createIndexesOnEmptyCollection(
+void ShardServerProcessInterface::createIndexesOnEmptyCollection(
     OperationContext* opCtx, const NamespaceString& ns, const std::vector<BSONObj>& indexSpecs) {
     auto cachedDbInfo =
         uassertStatusOK(Grid::get(opCtx)->catalogCache()->getDatabase(opCtx, ns.db()));
@@ -299,7 +292,8 @@ void MongoInterfaceShardServer::createIndexesOnEmptyCollection(
                                str::stream()
                                    << "write concern failed while running command " << cmdObj);
 }
-void MongoInterfaceShardServer::dropCollection(OperationContext* opCtx, const NamespaceString& ns) {
+void ShardServerProcessInterface::dropCollection(OperationContext* opCtx,
+                                                 const NamespaceString& ns) {
     // Build and execute the dropCollection command against the primary shard of the given
     // database.
     auto cachedDbInfo =
diff --git a/src/mongo/db/pipeline/process_interface_shardsvr.h b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface.h
index 66098e7377e..a7fa2b9198d 100644
--- a/src/mongo/db/pipeline/process_interface_shardsvr.h
+++ b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface.h
@@ -31,16 +31,16 @@
 
 #include "mongo/db/dbdirectclient.h"
 #include "mongo/db/pipeline/pipeline.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/common_mongod_process_interface.h"
 
 namespace mongo {
 
 /**
  * Specialized version of the MongoDInterface when this node is a shard server.
  */
-class MongoInterfaceShardServer final : public MongoInterfaceStandalone {
+class ShardServerProcessInterface final : public CommonMongodProcessInterface {
 public:
-    using MongoInterfaceStandalone::MongoInterfaceStandalone;
+    using CommonMongodProcessInterface::CommonMongodProcessInterface;
 
     void checkRoutingInfoEpochOrThrow(const boost::intrusive_ptr<ExpressionContext>& expCtx,
                                       const NamespaceString& nss,
diff --git a/src/mongo/db/pipeline/process_interface_standalone_test.cpp b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface_test.cpp
index e522111e395..14df45018df 100644
--- a/src/mongo/db/pipeline/process_interface_standalone_test.cpp
+++ b/src/mongo/db/pipeline/process_interface/shardsvr_process_interface_test.cpp
@@ -30,15 +30,15 @@
 #include "mongo/platform/basic.h"
 
 #include "mongo/db/pipeline/aggregation_context_fixture.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
 #include "mongo/unittest/unittest.h"
 
 namespace mongo {
 namespace {
 
-class MongoProcessInterfaceForTest : public MongoInterfaceStandalone {
+class MongoProcessInterfaceForTest : public NonShardServerProcessInterface {
 public:
-    using MongoInterfaceStandalone::MongoInterfaceStandalone;
+    using NonShardServerProcessInterface::NonShardServerProcessInterface;
 
     bool fieldsHaveSupportingUniqueIndex(const boost::intrusive_ptr<ExpressionContext>& expCtx,
                                          const NamespaceString& nss,
diff --git a/src/mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.cpp b/src/mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.cpp
index 9d979f1c308..cba2a97ffcc 100644
--- a/src/mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.cpp
+++ b/src/mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.cpp
@@ -29,7 +29,7 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.h"
+#include "mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.h"
 
 #include "mongo/db/pipeline/document_source.h"
 #include "mongo/db/pipeline/document_source_mock.h"
@@ -37,8 +37,7 @@
 
 namespace mongo {
 
-std::unique_ptr<Pipeline, PipelineDeleter>
-StubMongoProcessInterfaceLookupSingleDocument::makePipeline(
+std::unique_ptr<Pipeline, PipelineDeleter> StubLookupSingleDocumentProcessInterface::makePipeline(
     const std::vector<BSONObj>& rawPipeline,
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const MakePipelineOptions opts) {
@@ -57,7 +56,7 @@ StubMongoProcessInterfaceLookupSingleDocument::makePipeline(
 }
 
 std::unique_ptr<Pipeline, PipelineDeleter>
-StubMongoProcessInterfaceLookupSingleDocument::attachCursorSourceToPipelineForLocalRead(
+StubLookupSingleDocumentProcessInterface::attachCursorSourceToPipelineForLocalRead(
     const boost::intrusive_ptr<ExpressionContext>& expCtx, Pipeline* ownedPipeline) {
     std::unique_ptr<Pipeline, PipelineDeleter> pipeline(ownedPipeline,
                                                         PipelineDeleter(expCtx->opCtx));
@@ -66,15 +65,14 @@ StubMongoProcessInterfaceLookupSingleDocument::attachCursorSourceToPipelineForLo
 }
 
 std::unique_ptr<Pipeline, PipelineDeleter>
-StubMongoProcessInterfaceLookupSingleDocument::attachCursorSourceToPipeline(
+StubLookupSingleDocumentProcessInterface::attachCursorSourceToPipeline(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     Pipeline* ownedPipeline,
     bool allowTargetingShards) {
     return attachCursorSourceToPipelineForLocalRead(expCtx, ownedPipeline);
 }
 
-
-boost::optional<Document> StubMongoProcessInterfaceLookupSingleDocument::lookupSingleDocument(
+boost::optional<Document> StubLookupSingleDocumentProcessInterface::lookupSingleDocument(
     const boost::intrusive_ptr<ExpressionContext>& expCtx,
     const NamespaceString& nss,
     UUID collectionUUID,
diff --git a/src/mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.h b/src/mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.h
index 1a4956ce97d..421fb759ae2 100644
--- a/src/mongo/db/pipeline/stub_mongo_process_interface_lookup_single_document.h
+++ b/src/mongo/db/pipeline/process_interface/stub_lookup_single_document_process_interface.h
@@ -37,7 +37,7 @@
 #include "mongo/db/exec/shard_filterer.h"
 #include "mongo/db/pipeline/document_source.h"
 #include "mongo/db/pipeline/pipeline.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 
 namespace mongo {
 
@@ -62,10 +62,9 @@ public:
 /**
  * A mock MongoProcessInterface which allows mocking a foreign pipeline.
  */
-class StubMongoProcessInterfaceLookupSingleDocument final : public StubMongoProcessInterface {
+class StubLookupSingleDocumentProcessInterface final : public StubMongoProcessInterface {
 public:
-    StubMongoProcessInterfaceLookupSingleDocument(
-        std::deque<DocumentSource::GetNextResult> mockResults)
+    StubLookupSingleDocumentProcessInterface(std::deque<DocumentSource::GetNextResult> mockResults)
         : _mockResults(std::move(mockResults)) {}
 
     std::unique_ptr<Pipeline, PipelineDeleter> makePipeline(
diff --git a/src/mongo/db/pipeline/stub_mongo_process_interface.h b/src/mongo/db/pipeline/process_interface/stub_mongo_process_interface.h
index 5e7d0754888..69d7b5eec49 100644
--- a/src/mongo/db/pipeline/stub_mongo_process_interface.h
+++ b/src/mongo/db/pipeline/process_interface/stub_mongo_process_interface.h
@@ -29,8 +29,8 @@
 
 #pragma once
 
-#include "mongo/db/pipeline/mongo_process_interface.h"
 #include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/mongo_process_interface.h"
 
 #include "mongo/util/assert_util.h"
 
diff --git a/src/mongo/db/s/transaction_coordinator_curop.h b/src/mongo/db/s/transaction_coordinator_curop.h
index 4ab1d2a9798..8b69c916162 100644
--- a/src/mongo/db/s/transaction_coordinator_curop.h
+++ b/src/mongo/db/s/transaction_coordinator_curop.h
@@ -28,7 +28,7 @@
  */
 #pragma once
 
-#include "mongo/db/pipeline/mongos_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongos_process_interface.h"
 
 namespace mongo {
 
diff --git a/src/mongo/db/views/view_catalog.cpp b/src/mongo/db/views/view_catalog.cpp
index b09c3c00073..11003651962 100644
--- a/src/mongo/db/views/view_catalog.cpp
+++ b/src/mongo/db/views/view_catalog.cpp
@@ -49,7 +49,7 @@
 #include "mongo/db/pipeline/expression_context.h"
 #include "mongo/db/pipeline/lite_parsed_pipeline.h"
 #include "mongo/db/pipeline/pipeline.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
 #include "mongo/db/storage/recovery_unit.h"
 #include "mongo/db/views/resolved_view.h"
diff --git a/src/mongo/embedded/SConscript b/src/mongo/embedded/SConscript
index 14002f1dce1..8d943c53720 100644
--- a/src/mongo/embedded/SConscript
+++ b/src/mongo/embedded/SConscript
@@ -100,7 +100,7 @@ env.Library(
         '$BUILD_DIR/mongo/db/logical_session_cache',
         '$BUILD_DIR/mongo/db/logical_session_cache_impl',
         '$BUILD_DIR/mongo/db/op_observer_impl',
-        '$BUILD_DIR/mongo/db/pipeline/process_interface_standalone',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongod_process_interfaces',
         '$BUILD_DIR/mongo/db/repair_database_and_check_version',
         '$BUILD_DIR/mongo/db/repl/repl_coordinator_interface',
         '$BUILD_DIR/mongo/db/repl/replica_set_messages',
diff --git a/src/mongo/embedded/process_interface_factory_embedded.cpp b/src/mongo/embedded/process_interface_factory_embedded.cpp
index 4be510f2d3c..01b8d1c1d7e 100644
--- a/src/mongo/embedded/process_interface_factory_embedded.cpp
+++ b/src/mongo/embedded/process_interface_factory_embedded.cpp
@@ -30,13 +30,13 @@
 #include "mongo/platform/basic.h"
 
 #include "mongo/base/shim.h"
-#include "mongo/db/pipeline/process_interface_standalone.h"
+#include "mongo/db/pipeline/process_interface/non_shardsvr_process_interface.h"
 
 namespace mongo {
 namespace {
 
 std::shared_ptr<MongoProcessInterface> mongoProcessInterfaceCreateImpl(OperationContext* opCtx) {
-    return std::make_shared<MongoInterfaceStandalone>(opCtx);
+    return std::make_shared<NonShardServerProcessInterface>(opCtx);
 }
 
 auto mongoProcessInterfaceCreateRegistration = MONGO_WEAK_FUNCTION_REGISTRATION(
diff --git a/src/mongo/s/commands/cluster_map_reduce_agg.cpp b/src/mongo/s/commands/cluster_map_reduce_agg.cpp
index e52ae32216b..54d71a81b4c 100644
--- a/src/mongo/s/commands/cluster_map_reduce_agg.cpp
+++ b/src/mongo/s/commands/cluster_map_reduce_agg.cpp
@@ -40,7 +40,7 @@
 #include "mongo/db/commands/map_reduce_agg.h"
 #include "mongo/db/commands/map_reduce_gen.h"
 #include "mongo/db/commands/mr_common.h"
-#include "mongo/db/pipeline/mongos_process_interface.h"
+#include "mongo/db/pipeline/process_interface/mongos_process_interface.h"
 #include "mongo/db/pipeline/sharded_agg_helpers.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
 #include "mongo/db/query/cursor_response.h"
@@ -96,7 +96,7 @@ auto makeExpressionContext(OperationContext* opCtx,
         nss,
         runtimeConstants,
         std::move(resolvedCollator),
-        std::make_shared<MongoSInterface>(),
+        std::make_shared<MongosProcessInterface>(),
         std::move(resolvedNamespaces),
         boost::none);  // uuid
     expCtx->inMongos = true;
diff --git a/src/mongo/s/query/SConscript b/src/mongo/s/query/SConscript
index 9763e2bcf5d..373f0efff52 100644
--- a/src/mongo/s/query/SConscript
+++ b/src/mongo/s/query/SConscript
@@ -34,7 +34,7 @@ env.Library(
     LIBDEPS=[
         '$BUILD_DIR/mongo/db/pipeline/pipeline',
         '$BUILD_DIR/mongo/s/query/cluster_client_cursor',
-        '$BUILD_DIR/mongo/db/pipeline/mongos_process_interface',
+        '$BUILD_DIR/mongo/db/pipeline/process_interface/mongos_process_interface',
         '$BUILD_DIR/mongo/db/pipeline/sharded_agg_helpers',
         '$BUILD_DIR/mongo/db/views/views',
         'cluster_query',
diff --git a/src/mongo/s/query/cluster_aggregate.cpp b/src/mongo/s/query/cluster_aggregate.cpp
index f24dbfb8aa0..c91f3436d16 100644
--- a/src/mongo/s/query/cluster_aggregate.cpp
+++ b/src/mongo/s/query/cluster_aggregate.cpp
@@ -45,8 +45,8 @@
 #include "mongo/db/pipeline/document_source_out.h"
 #include "mongo/db/pipeline/expression_context.h"
 #include "mongo/db/pipeline/lite_parsed_pipeline.h"
-#include "mongo/db/pipeline/mongos_process_interface.h"
 #include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/process_interface/mongos_process_interface.h"
 #include "mongo/db/pipeline/sharded_agg_helpers.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
 #include "mongo/db/query/cursor_response.h"
@@ -120,7 +120,7 @@ boost::intrusive_ptr<ExpressionContext> makeExpressionContext(
     auto mergeCtx = new ExpressionContext(opCtx,
                                           request,
                                           std::move(collation),
-                                          std::make_shared<MongoSInterface>(),
+                                          std::make_shared<MongosProcessInterface>(),
                                           std::move(resolvedNamespaces),
                                           uuid);
 
diff --git a/src/mongo/s/query/cluster_exchange_test.cpp b/src/mongo/s/query/cluster_exchange_test.cpp
index 1060e752c95..a49ff306214 100644
--- a/src/mongo/s/query/cluster_exchange_test.cpp
+++ b/src/mongo/s/query/cluster_exchange_test.cpp
@@ -39,8 +39,8 @@
 #include "mongo/db/pipeline/document_source_project.h"
 #include "mongo/db/pipeline/document_source_sort.h"
 #include "mongo/db/pipeline/expression_context_for_test.h"
+#include "mongo/db/pipeline/process_interface/stub_mongo_process_interface.h"
 #include "mongo/db/pipeline/sharded_agg_helpers.h"
-#include "mongo/db/pipeline/stub_mongo_process_interface.h"
 #include "mongo/s/catalog/type_shard.h"
 #include "mongo/s/catalog_cache_test_fixture.h"
 #include "mongo/unittest/unittest.h"