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diff --git a/src/mongo/db/s/collmod_coordinator_pre60_compatible.h b/src/mongo/db/s/collmod_coordinator_pre60_compatible.h
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+/**
+ *    Copyright (C) 2021-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/s/collmod_coordinator_document_gen.h"
+#include "mongo/db/s/sharding_ddl_coordinator.h"
+#include "mongo/s/request_types/sharded_ddl_commands_gen.h"
+
+namespace mongo {
+
+class CollModCoordinatorPre60Compatible final : public ShardingDDLCoordinator {
+public:
+    using StateDoc = CollModCoordinatorDocument;
+    using Phase = CollModCoordinatorPhaseEnum;
+
+    CollModCoordinatorPre60Compatible(ShardingDDLCoordinatorService* service,
+                                      const BSONObj& initialState);
+
+    void checkIfOptionsConflict(const BSONObj& doc) const override;
+
+    boost::optional<BSONObj> reportForCurrentOp(
+        MongoProcessInterface::CurrentOpConnectionsMode connMode,
+        MongoProcessInterface::CurrentOpSessionsMode sessionMode) noexcept override;
+
+    /**
+     * Waits for the termination of the parent DDLCoordinator (so all the resources are liberated)
+     * and then return the result.
+     */
+    BSONObj getResult(OperationContext* opCtx) {
+        getCompletionFuture().get(opCtx);
+        invariant(_result.is_initialized());
+        return *_result;
+    }
+
+private:
+    ShardingDDLCoordinatorMetadata const& metadata() const override {
+        return _doc.getShardingDDLCoordinatorMetadata();
+    }
+
+    ExecutorFuture<void> _runImpl(std::shared_ptr<executor::ScopedTaskExecutor> executor,
+                                  const CancellationToken& token) noexcept override;
+
+    template <typename Func>
+    auto _executePhase(const Phase& newPhase, Func&& func) {
+        return [=] {
+            const auto& currPhase = _doc.getPhase();
+
+            if (currPhase > newPhase) {
+                // Do not execute this phase if we already reached a subsequent one.
+                return;
+            }
+            if (currPhase < newPhase) {
+                // Persist the new phase if this is the first time we are executing it.
+                _enterPhase(newPhase);
+            }
+            return func();
+        };
+    }
+
+    void _enterPhase(Phase newPhase);
+
+    void _performNoopRetryableWriteOnParticipants(
+        OperationContext* opCtx, const std::shared_ptr<executor::TaskExecutor>& executor);
+
+    BSONObj _initialState;
+    CollModCoordinatorDocument _doc;
+    boost::optional<BSONObj> _result;
+};
+
+}  // namespace mongo