diff --git a/CMakeLists.txt b/CMakeLists.txt
index 52c5f4c..7f4f961 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -49,6 +49,13 @@ file(GLOB_RECURSE SOURCES "src/*.c")
 # Create core library
 add_library(dnlp_diff ${SOURCES})
 
+# Optional peak-memory tracking via the sp_malloc/sp_free counters. OFF by default
+# so the library carries no mutable global state.
+option(SP_TRACK_MEMORY "Track peak memory usage via sp_malloc/sp_free counters" OFF)
+if(SP_TRACK_MEMORY)
+    target_compile_definitions(dnlp_diff PUBLIC SP_TRACK_MEMORY)
+endif()
+
 # Link math library (Unix/Linux only)
 if(NOT MSVC)
     target_link_libraries(dnlp_diff m)
diff --git a/include/utils/tracked_alloc.h b/include/utils/tracked_alloc.h
index 50c3351..c5f7b38 100644
--- a/include/utils/tracked_alloc.h
+++ b/include/utils/tracked_alloc.h
@@ -21,6 +21,10 @@
 #include <stddef.h>
 #include <stdlib.h>
 
+/* Peak-memory tracking is only compiled in with -DSP_TRACK_MEMORY=ON (CMake
+   option). Otherwise sp_* are plain malloc/calloc/realloc/free. */
+#ifdef SP_TRACK_MEMORY
+
 /* Platform shim for "how many usable bytes are at this malloc'd pointer".
     Used to track total live bytes */
 #if defined(__APPLE__)
@@ -95,4 +99,30 @@ static inline void *sp_realloc(void *ptr, size_t size)
     return new_ptr;
 }
 
+#else /* !SP_TRACK_MEMORY */
+
+/* Tracking disabled (default): the wrappers forward straight to libc and the
+   library has no mutable global state. */
+static inline void *sp_malloc(size_t size)
+{
+    return malloc(size);
+}
+
+static inline void *sp_calloc(size_t count, size_t size)
+{
+    return calloc(count, size);
+}
+
+static inline void sp_free(void *ptr)
+{
+    free(ptr);
+}
+
+static inline void *sp_realloc(void *ptr, size_t size)
+{
+    return realloc(ptr, size);
+}
+
+#endif /* SP_TRACK_MEMORY */
+
 #endif /* TRACKED_ALLOC_H */
diff --git a/src/problem.c b/src/problem.c
index 11b49f0..4b753b5 100644
--- a/src/problem.c
+++ b/src/problem.c
@@ -32,10 +32,12 @@ static void problem_lagrange_hess_fill_sparsity(problem *prob, int *iwork);
 problem *new_problem(expr *objective, expr **constraints, int n_constraints,
                      bool verbose)
 {
+#ifdef SP_TRACK_MEMORY
     /* we don't reset g_peak_bytes or g_allocated_bytes since allocations
        using sp_malloc/sp_calloc might have happened before new_problem in eg.,
        left_matmul, and their frees will subtract from this counter. */
     g_peak_bytes = g_allocated_bytes;
+#endif
     problem *prob = (problem *) sp_calloc(1, sizeof(problem));
     if (!prob) return NULL;
 
@@ -305,6 +307,7 @@ void problem_init_derivatives(problem *prob)
     problem_init_hessian(prob);
 }
 
+#ifdef SP_TRACK_MEMORY
 static inline void format_memory(size_t bytes, char *buf, size_t buf_size)
 {
     if (bytes < 1024)
@@ -320,6 +323,7 @@ static inline void format_memory(size_t bytes, char *buf, size_t buf_size)
         snprintf(buf, buf_size, "%.2f MB", (double) bytes / (1024.0 * 1024.0));
     }
 }
+#endif
 
 static inline void print_end_message(const Diff_engine_stats *stats)
 {
@@ -337,9 +341,11 @@ static inline void print_end_message(const Diff_engine_stats *stats)
     printf("  Affine constraints (nnz):               %d\n", stats->nnz_affine);
     printf("  Jacobian nonlinear constraints (nnz):   %d\n", stats->nnz_nonlinear);
     printf("  Lagrange Hessian (nnz):                 %d\n", stats->nnz_hessian);
+#ifdef SP_TRACK_MEMORY
     char mem_buf[64];
     format_memory(stats->memory_bytes, mem_buf, sizeof(mem_buf));
     printf("  Peak memory:                            %s\n", mem_buf);
+#endif
 
     printf("\nTiming (seconds):\n");
     printf("  Derivative structure (sparsity):     %8.3f\n",
@@ -367,7 +373,9 @@ void free_problem(problem *prob)
 {
     if (prob == NULL) return;
 
+#ifdef SP_TRACK_MEMORY
     prob->stats.memory_bytes = g_peak_bytes;
+#endif
     if (prob->verbose)
     {
         print_end_message(&prob->stats);
diff --git a/src/utils/permuted_dense_linalg.c b/src/utils/permuted_dense_linalg.c
index 4fdf806..e1703cd 100644
--- a/src/utils/permuted_dense_linalg.c
+++ b/src/utils/permuted_dense_linalg.c
@@ -561,10 +561,10 @@ void BTDA_csc_pd_fill_values(const CSC_matrix *B, const double *d,
 #if defined(__GNUC__) || defined(__clang__)
 __attribute__((unused))
 #endif
-static void
-BTDA_csc_pd_fill_values_via_transpose_dead(const CSC_matrix *B, const double *d,
-                                           const permuted_dense *A,
-                                           permuted_dense *C)
+static void BTDA_csc_pd_fill_values_via_transpose_dead(const CSC_matrix *B,
+                                                       const double *d,
+                                                       const permuted_dense *A,
+                                                       permuted_dense *C)
 {
     if (C->base.nnz == 0)
     {
diff --git a/src/utils/tracked_alloc.c b/src/utils/tracked_alloc.c
index 9b0f4d8..8caf72d 100644
--- a/src/utils/tracked_alloc.c
+++ b/src/utils/tracked_alloc.c
@@ -17,5 +17,7 @@
  */
 #include "utils/tracked_alloc.h"
 
+#ifdef SP_TRACK_MEMORY
 size_t g_allocated_bytes = 0;
 size_t g_peak_bytes = 0;
+#endif