From 70945e64a32a7af95a2a9db23e82ffd58e9c512f Mon Sep 17 00:00:00 2001
From: Michael Tupek <tupek2@llnl.gov>
Date: Thu, 19 Mar 2026 13:58:48 -0700
Subject: [PATCH 1/2] Allow some backwards compatability.

---
 src/gretl/data_store.cpp | 6 ++++++
 src/gretl/data_store.hpp | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/src/gretl/data_store.cpp b/src/gretl/data_store.cpp
index bfbaaaf..497dd0f 100644
--- a/src/gretl/data_store.cpp
+++ b/src/gretl/data_store.cpp
@@ -7,11 +7,17 @@
 #include <any>
 #include "data_store.hpp"
 #include "state.hpp"
+#include "wang_checkpoint_strategy.hpp"
 #include <iostream>
 #include <iomanip>
 
 namespace gretl {
 
+DataStore::DataStore(size_t checkpoint_budget)
+    : DataStore(std::make_unique<WangCheckpointStrategy>(checkpoint_budget))
+{
+}
+
 DataStore::DataStore(std::unique_ptr<CheckpointStrategy> strategy) : checkpointStrategy_(std::move(strategy))
 {
   currentStep_ = 0;
diff --git a/src/gretl/data_store.hpp b/src/gretl/data_store.hpp
index 9e9955f..5f27bf0 100644
--- a/src/gretl/data_store.hpp
+++ b/src/gretl/data_store.hpp
@@ -55,6 +55,9 @@ struct defaultInitializeZeroDual {
 /// checkpointing state information, and its backpropagated sensitivities
 class DataStore {
  public:
+  /// @brief Backward-compat constructor using a Wang checkpoint budget.
+  explicit DataStore(size_t checkpoint_budget);
+
   /// @brief Constructor requiring a checkpoint strategy.
   /// @param strategy a checkpoint strategy implementation (e.g., WangCheckpointStrategy,
   /// StrummWaltherCheckpointStrategy)

From 0d867b28a90bd127947c50f72e3ca687105b87e3 Mon Sep 17 00:00:00 2001
From: Michael Tupek <tupek2@llnl.gov>
Date: Thu, 19 Mar 2026 14:20:38 -0700
Subject: [PATCH 2/2] Style.

---
 src/gretl/data_store.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/gretl/data_store.cpp b/src/gretl/data_store.cpp
index 497dd0f..679092f 100644
--- a/src/gretl/data_store.cpp
+++ b/src/gretl/data_store.cpp
@@ -13,8 +13,7 @@
 
 namespace gretl {
 
-DataStore::DataStore(size_t checkpoint_budget)
-    : DataStore(std::make_unique<WangCheckpointStrategy>(checkpoint_budget))
+DataStore::DataStore(size_t checkpoint_budget) : DataStore(std::make_unique<WangCheckpointStrategy>(checkpoint_budget))
 {
 }