diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5dbcd8145..f889aa776 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+#### Added
+ - New function `secp256k1_ec_pubkey_sort` that sorts public keys using lexicographic (of compressed serialization) order.
+
 #### Changed
  - The implementation of the point multiplication algorithm used for signing and public key generation was changed, resulting in improved performance for those operations.
    - The related configure option `--ecmult-gen-precision` was replaced with `--ecmult-gen-kb` (`ECMULT_GEN_KB` for CMake).
diff --git a/Makefile.am b/Makefile.am
index 329f86ca8..1b8d54a98 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -66,6 +66,8 @@ noinst_HEADERS += src/field.h
 noinst_HEADERS += src/field_impl.h
 noinst_HEADERS += src/bench.h
 noinst_HEADERS += src/wycheproof/ecdsa_secp256k1_sha256_bitcoin_test.h
+noinst_HEADERS += src/hsort.h
+noinst_HEADERS += src/hsort_impl.h
 noinst_HEADERS += contrib/lax_der_parsing.h
 noinst_HEADERS += contrib/lax_der_parsing.c
 noinst_HEADERS += contrib/lax_der_privatekey_parsing.h
diff --git a/include/secp256k1.h b/include/secp256k1.h
index f4053f2a9..cfbdd528c 100644
--- a/include/secp256k1.h
+++ b/include/secp256k1.h
@@ -474,6 +474,20 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_cmp(
     const secp256k1_pubkey *pubkey2
 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
 
+/** Sort public keys using lexicographic (of compressed serialization) order
+ *
+ *  Returns: 0 if the arguments are invalid. 1 otherwise.
+ *
+ *  Args:     ctx: pointer to a context object
+ *  In:   pubkeys: array of pointers to pubkeys to sort
+ *      n_pubkeys: number of elements in the pubkeys array
+ */
+SECP256K1_API int secp256k1_ec_pubkey_sort(
+    const secp256k1_context *ctx,
+    const secp256k1_pubkey **pubkeys,
+    size_t n_pubkeys
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+
 /** Parse an ECDSA signature in compact (64 bytes) format.
  *
  *  Returns: 1 when the signature could be parsed, 0 otherwise.
diff --git a/include/secp256k1_extrakeys.h b/include/secp256k1_extrakeys.h
index 9f0911634..ad70b92f9 100644
--- a/include/secp256k1_extrakeys.h
+++ b/include/secp256k1_extrakeys.h
@@ -240,21 +240,6 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_xonly_tweak_add
     const unsigned char *tweak32
 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
 
-/** Sort public keys using lexicographic order of their compressed
- *  serialization.
- *
- *  Returns: 0 if the arguments are invalid. 1 otherwise.
- *
- *  Args:     ctx: pointer to a context object
- *  In:   pubkeys: array of pointers to pubkeys to sort
- *      n_pubkeys: number of elements in the pubkeys array
- */
-SECP256K1_API int secp256k1_pubkey_sort(
-    const secp256k1_context *ctx,
-    const secp256k1_pubkey **pubkeys,
-    size_t n_pubkeys
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/secp256k1_musig.h b/include/secp256k1_musig.h
index 28ecf1efc..0c539e8a5 100644
--- a/include/secp256k1_musig.h
+++ b/include/secp256k1_musig.h
@@ -186,7 +186,7 @@ SECP256K1_API int secp256k1_musig_partial_sig_parse(
  *
  *  Different orders of `pubkeys` result in different `agg_pk`s.
  *
- *  Before aggregating, the pubkeys can be sorted with `secp256k1_pubkey_sort`
+ *  Before aggregating, the pubkeys can be sorted with `secp256k1_ec_pubkey_sort`
  *  which ensures the same `agg_pk` result for the same multiset of pubkeys.
  *  This is useful to do before `pubkey_agg`, such that the order of pubkeys
  *  does not affect the aggregate public key.
diff --git a/src/modules/extrakeys/hsort.h b/src/hsort.h
similarity index 52%
rename from src/modules/extrakeys/hsort.h
rename to src/hsort.h
index 5352ef1e3..d54995caa 100644
--- a/src/modules/extrakeys/hsort.h
+++ b/src/hsort.h
@@ -13,8 +13,19 @@
 /* In-place, iterative heapsort with an interface matching glibc's qsort_r. This
  * is preferred over standard library implementations because they generally
  * make no guarantee about being fast for malicious inputs.
+ * Remember that heapsort is unstable.
  *
- * See the qsort_r manpage for a description of the interface.
+ * In/Out: ptr: pointer to the array to sort. The contents of the array are
+ *              sorted in ascending order according to the comparison function.
+ * In:   count: number of elements in the array.
+ *        size: size in bytes of each element.
+ *         cmp: pointer to a comparison function that is called with two
+ *              arguments that point to the objects being compared. The cmp_data
+ *              argument of secp256k1_hsort is passed as third argument. The
+ *              function must return an integer less than, equal to, or greater
+ *              than zero if the first argument is considered to be respectively
+ *              less than, equal to, or greater than the second.
+ *    cmp_data: pointer passed as third argument to cmp.
  */
 static void secp256k1_hsort(void *ptr, size_t count, size_t size,
                             int (*cmp)(const void *, const void *, void *),
diff --git a/src/modules/extrakeys/hsort_impl.h b/src/hsort_impl.h
similarity index 52%
rename from src/modules/extrakeys/hsort_impl.h
rename to src/hsort_impl.h
index e05aefdf8..1c674ff1c 100644
--- a/src/modules/extrakeys/hsort_impl.h
+++ b/src/hsort_impl.h
@@ -13,33 +13,42 @@
  * compares as less than or equal to the element at index parent(i) = (i-1)/2.
  */
 
-static SECP256K1_INLINE size_t child1(size_t i) {
+static SECP256K1_INLINE size_t secp256k1_heap_child1(size_t i) {
     VERIFY_CHECK(i <= (SIZE_MAX - 1)/2);
     return 2*i + 1;
 }
 
-static SECP256K1_INLINE size_t child2(size_t i) {
+static SECP256K1_INLINE size_t secp256k1_heap_child2(size_t i) {
     VERIFY_CHECK(i <= SIZE_MAX/2 - 1);
-    return child1(i)+1;
+    return secp256k1_heap_child1(i)+1;
 }
 
-static SECP256K1_INLINE void heap_swap64(unsigned char *a, size_t i, size_t j, size_t stride) {
+static SECP256K1_INLINE void secp256k1_heap_swap64(unsigned char *a, unsigned char *b, size_t len) {
     unsigned char tmp[64];
-    VERIFY_CHECK(stride <= 64);
-    memcpy(tmp, a + i*stride, stride);
-    memmove(a + i*stride, a + j*stride, stride);
-    memcpy(a + j*stride, tmp, stride);
+    VERIFY_CHECK(len <= 64);
+    memcpy(tmp, a, len);
+    memmove(a, b, len);
+    memcpy(b, tmp, len);
 }
 
-static SECP256K1_INLINE void heap_swap(unsigned char *a, size_t i, size_t j, size_t stride) {
-    while (64 < stride) {
-        heap_swap64(a + (stride - 64), i, j, 64);
-        stride -= 64;
+static SECP256K1_INLINE void secp256k1_heap_swap(unsigned char *arr, size_t i, size_t j, size_t stride) {
+    unsigned char *a = arr + i*stride;
+    unsigned char *b = arr + j*stride;
+    size_t len = stride;
+    while (64 < len) {
+        secp256k1_heap_swap64(a + (len - 64), b + (len - 64), 64);
+        len -= 64;
     }
-    heap_swap64(a, i, j, stride);
+    secp256k1_heap_swap64(a, b, len);
 }
 
-static SECP256K1_INLINE void heap_down(unsigned char *a, size_t i, size_t heap_size, size_t stride,
+/* This function accepts an array arr containing heap_size elements, each of
+ * size stride. The elements in the array at indices >i satisfy the max-heap
+ * property, i.e., for any element at index j (where j > i), all of its children
+ * are smaller than the element itself. The purpose of the function is to update
+ * the array so that all elements at indices >=i satisfy the max-heap
+ * property. */
+static SECP256K1_INLINE void secp256k1_heap_down(unsigned char *arr, size_t i, size_t heap_size, size_t stride,
                             int (*cmp)(const void *, const void *, void *), void *cmp_data) {
     while (i < heap_size/2) {
         VERIFY_CHECK(i <= SIZE_MAX/2 - 1);
@@ -50,7 +59,7 @@ static SECP256K1_INLINE void heap_down(unsigned char *a, size_t i, size_t heap_s
          * 2*i <= SIZE_MAX - 2
          */
 
-        VERIFY_CHECK(child1(i) < heap_size);
+        VERIFY_CHECK(secp256k1_heap_child1(i) < heap_size);
         /* Proof:
          * i < heap_size/2
          * i + 1 <= heap_size/2
@@ -59,7 +68,7 @@ static SECP256K1_INLINE void heap_down(unsigned char *a, size_t i, size_t heap_s
          * child1(i) < heap_size
          */
 
-        /* Let [x] be notation for the contents at a[x*stride].
+        /* Let [x] be notation for the contents at arr[x*stride].
          *
          * If [child1(i)] > [i] and [child2(i)] > [i],
          *   swap [i] with the larger child to ensure the new parent is larger
@@ -68,20 +77,20 @@ static SECP256K1_INLINE void heap_down(unsigned char *a, size_t i, size_t heap_s
          * Else if [child1(i)] > [i], swap [i] with [child1(i)].
          * Else if [child2(i)] > [i], swap [i] with [child2(i)].
          */
-        if (child2(i) < heap_size
-                && 0 <= cmp(a + child2(i)*stride, a + child1(i)*stride, cmp_data)) {
-            if (0 < cmp(a + child2(i)*stride, a +         i*stride, cmp_data)) {
-                heap_swap(a, i, child2(i), stride);
-                i = child2(i);
+        if (secp256k1_heap_child2(i) < heap_size
+                && 0 <= cmp(arr + secp256k1_heap_child2(i)*stride, arr + secp256k1_heap_child1(i)*stride, cmp_data)) {
+            if (0 < cmp(arr + secp256k1_heap_child2(i)*stride, arr + i*stride, cmp_data)) {
+                secp256k1_heap_swap(arr, i, secp256k1_heap_child2(i), stride);
+                i = secp256k1_heap_child2(i);
             } else {
                 /* At this point we have [child2(i)] >= [child1(i)] and we have
                  * [child2(i)] <= [i], and thus [child1(i)] <= [i] which means
                  * that the next comparison can be skipped. */
                 return;
             }
-        } else if (0 < cmp(a + child1(i)*stride, a +         i*stride, cmp_data)) {
-            heap_swap(a, i, child1(i), stride);
-            i = child1(i);
+        } else if (0 < cmp(arr + secp256k1_heap_child1(i)*stride, arr +         i*stride, cmp_data)) {
+            secp256k1_heap_swap(arr, i, secp256k1_heap_child1(i), stride);
+            i = secp256k1_heap_child1(i);
         } else {
             return;
         }
@@ -98,18 +107,18 @@ static SECP256K1_INLINE void heap_down(unsigned char *a, size_t i, size_t heap_s
 /* In-place heap sort. */
 static void secp256k1_hsort(void *ptr, size_t count, size_t size,
                             int (*cmp)(const void *, const void *, void *),
-                            void *cmp_data ) {
+                            void *cmp_data) {
     size_t i;
 
-    for(i = count/2; 0 < i; --i) {
-        heap_down(ptr, i-1, count, size, cmp, cmp_data);
+    for (i = count/2; 0 < i; --i) {
+        secp256k1_heap_down(ptr, i-1, count, size, cmp, cmp_data);
     }
-    for(i = count; 1 < i; --i) {
+    for (i = count; 1 < i; --i) {
         /* Extract the largest value from the heap */
-        heap_swap(ptr, 0, i-1, size);
+        secp256k1_heap_swap(ptr, 0, i-1, size);
 
         /* Repair the heap condition */
-        heap_down(ptr, 0, i-1, size, cmp, cmp_data);
+        secp256k1_heap_down(ptr, 0, i-1, size, cmp, cmp_data);
     }
 }
 
diff --git a/src/modules/extrakeys/Makefile.am.include b/src/modules/extrakeys/Makefile.am.include
index fe496fd22..622d8bb49 100644
--- a/src/modules/extrakeys/Makefile.am.include
+++ b/src/modules/extrakeys/Makefile.am.include
@@ -1,6 +1,4 @@
 include_HEADERS += include/secp256k1_extrakeys.h
 noinst_HEADERS += src/modules/extrakeys/tests_impl.h
 noinst_HEADERS += src/modules/extrakeys/tests_exhaustive_impl.h
-noinst_HEADERS += src/modules/extrakeys/main_impl.h
-noinst_HEADERS += src/modules/extrakeys/hsort.h
-noinst_HEADERS += src/modules/extrakeys/hsort_impl.h
+noinst_HEADERS += src/modules/extrakeys/main_impl.h
\ No newline at end of file
diff --git a/src/modules/extrakeys/main_impl.h b/src/modules/extrakeys/main_impl.h
index 2ba414653..0c7e26677 100644
--- a/src/modules/extrakeys/main_impl.h
+++ b/src/modules/extrakeys/main_impl.h
@@ -9,7 +9,6 @@
 
 #include "../../../include/secp256k1.h"
 #include "../../../include/secp256k1_extrakeys.h"
-#include "hsort_impl.h"
 #include "../../util.h"
 
 static SECP256K1_INLINE int secp256k1_xonly_pubkey_load(const secp256k1_context* ctx, secp256k1_ge *ge, const secp256k1_xonly_pubkey *pubkey) {
@@ -283,38 +282,4 @@ int secp256k1_keypair_xonly_tweak_add(const secp256k1_context* ctx, secp256k1_ke
     return ret;
 }
 
-/* This struct wraps a const context pointer to satisfy the secp256k1_hsort api
- * which expects a non-const cmp_data pointer. */
-typedef struct {
-    const secp256k1_context *ctx;
-} secp256k1_pubkey_sort_cmp_data;
-
-static int secp256k1_pubkey_sort_cmp(const void* pk1, const void* pk2, void *cmp_data) {
-    return secp256k1_ec_pubkey_cmp(((secp256k1_pubkey_sort_cmp_data*)cmp_data)->ctx,
-                                  *(secp256k1_pubkey **)pk1,
-                                  *(secp256k1_pubkey **)pk2);
-}
-
-int secp256k1_pubkey_sort(const secp256k1_context* ctx, const secp256k1_pubkey **pubkeys, size_t n_pubkeys) {
-    secp256k1_pubkey_sort_cmp_data cmp_data;
-    VERIFY_CHECK(ctx != NULL);
-    ARG_CHECK(pubkeys != NULL);
-
-    cmp_data.ctx = ctx;
-
-    /* Suppress wrong warning (fixed in MSVC 19.33) */
-    #if defined(_MSC_VER) && (_MSC_VER < 1933)
-    #pragma warning(push)
-    #pragma warning(disable: 4090)
-    #endif
-
-    secp256k1_hsort(pubkeys, n_pubkeys, sizeof(*pubkeys), secp256k1_pubkey_sort_cmp, &cmp_data);
-
-    #if defined(_MSC_VER) && (_MSC_VER < 1933)
-    #pragma warning(pop)
-    #endif
-
-    return 1;
-}
-
 #endif
diff --git a/src/modules/extrakeys/tests_impl.h b/src/modules/extrakeys/tests_impl.h
index 1f10ceed9..45521d174 100644
--- a/src/modules/extrakeys/tests_impl.h
+++ b/src/modules/extrakeys/tests_impl.h
@@ -467,196 +467,6 @@ static void test_keypair_add(void) {
     }
 }
 
-static void test_hsort_is_sorted(int *ints, size_t n) {
-    size_t i;
-    for (i = 1; i < n; i++) {
-        CHECK(ints[i-1] <= ints[i]);
-    }
-}
-
-static int test_hsort_cmp(const void *i1, const void *i2, void *counter) {
-  *(size_t*)counter += 1;
-  return *(int*)i1 - *(int*)i2;
-}
-
-#define NUM 64
-static void test_hsort(void) {
-    int ints[NUM] = { 0 };
-    size_t counter = 0;
-    int i, j;
-
-    secp256k1_hsort(ints, 0, sizeof(ints[0]), test_hsort_cmp, &counter);
-    CHECK(counter == 0);
-    secp256k1_hsort(ints, 1, sizeof(ints[0]), test_hsort_cmp, &counter);
-    CHECK(counter == 0);
-    secp256k1_hsort(ints, NUM, sizeof(ints[0]), test_hsort_cmp, &counter);
-    CHECK(counter > 0);
-    test_hsort_is_sorted(ints, NUM);
-
-    /* Test hsort with length n array and random elements in
-     * [-interval/2, interval/2] */
-    for (i = 0; i < COUNT; i++) {
-        int n = secp256k1_testrand_int(NUM);
-        int interval = secp256k1_testrand_int(63) + 1;
-        for (j = 0; j < n; j++) {
-            ints[j] = secp256k1_testrand_int(interval) - interval/2;
-        }
-        secp256k1_hsort(ints, n, sizeof(ints[0]), test_hsort_cmp, &counter);
-        test_hsort_is_sorted(ints, n);
-    }
-}
-#undef NUM
-
-static void test_sort_helper(secp256k1_pubkey *pk, size_t *pk_order, size_t n_pk) {
-    size_t i;
-    const secp256k1_pubkey *pk_test[5];
-
-    for (i = 0; i < n_pk; i++) {
-        pk_test[i] = &pk[pk_order[i]];
-    }
-    secp256k1_pubkey_sort(CTX, pk_test, n_pk);
-    for (i = 0; i < n_pk; i++) {
-        CHECK(secp256k1_memcmp_var(pk_test[i], &pk[i], sizeof(*pk_test[i])) == 0);
-    }
-}
-
-static void permute(size_t *arr, size_t n) {
-    size_t i;
-    for (i = n - 1; i >= 1; i--) {
-        size_t tmp, j;
-        j = secp256k1_testrand_int(i + 1);
-        tmp = arr[i];
-        arr[i] = arr[j];
-        arr[j] = tmp;
-    }
-}
-
-static void rand_pk(secp256k1_pubkey *pk) {
-    unsigned char seckey[32];
-    secp256k1_keypair keypair;
-    secp256k1_testrand256(seckey);
-    CHECK(secp256k1_keypair_create(CTX, &keypair, seckey) == 1);
-    CHECK(secp256k1_keypair_pub(CTX, pk, &keypair) == 1);
-}
-
-static void test_sort_api(void) {
-    secp256k1_pubkey pks[2];
-    const secp256k1_pubkey *pks_ptr[2];
-
-    pks_ptr[0] = &pks[0];
-    pks_ptr[1] = &pks[1];
-
-    rand_pk(&pks[0]);
-    rand_pk(&pks[1]);
-
-    CHECK(secp256k1_pubkey_sort(CTX, pks_ptr, 2) == 1);
-    CHECK_ILLEGAL(CTX, secp256k1_pubkey_sort(CTX, NULL, 2));
-    CHECK(secp256k1_pubkey_sort(CTX, pks_ptr, 0) == 1);
-    /* Test illegal public keys */
-    memset(&pks[0], 0, sizeof(pks[0]));
-    CHECK_ILLEGAL_VOID(CTX, CHECK(secp256k1_pubkey_sort(CTX, pks_ptr, 2) == 1));
-    memset(&pks[1], 0, sizeof(pks[1]));
-    {
-        int32_t ecount = 0;
-        secp256k1_context_set_illegal_callback(CTX, counting_callback_fn, &ecount);
-        CHECK(secp256k1_pubkey_sort(CTX, pks_ptr, 2) == 1);
-        CHECK(ecount == 2);
-        secp256k1_context_set_illegal_callback(CTX, NULL, NULL);
-    }
-}
-
-static void test_sort(void) {
-    secp256k1_pubkey pk[5];
-    unsigned char pk_ser[5][33] = {
-        { 0x02, 0x08 },
-        { 0x02, 0x0b },
-        { 0x02, 0x0c },
-        { 0x03, 0x05 },
-        { 0x03, 0x0a },
-    };
-    int i;
-    size_t pk_order[5] = { 0, 1, 2, 3, 4 };
-
-    for (i = 0; i < 5; i++) {
-        CHECK(secp256k1_ec_pubkey_parse(CTX, &pk[i], pk_ser[i], sizeof(pk_ser[i])));
-    }
-
-    permute(pk_order, 1);
-    test_sort_helper(pk, pk_order, 1);
-    permute(pk_order, 2);
-    test_sort_helper(pk, pk_order, 2);
-    permute(pk_order, 3);
-    test_sort_helper(pk, pk_order, 3);
-    for (i = 0; i < COUNT; i++) {
-        permute(pk_order, 4);
-        test_sort_helper(pk, pk_order, 4);
-    }
-    for (i = 0; i < COUNT; i++) {
-        permute(pk_order, 5);
-        test_sort_helper(pk, pk_order, 5);
-    }
-    /* Check that sorting also works for random pubkeys */
-    for (i = 0; i < COUNT; i++) {
-        int j;
-        const secp256k1_pubkey *pk_ptr[5];
-        for (j = 0; j < 5; j++) {
-            rand_pk(&pk[j]);
-            pk_ptr[j] = &pk[j];
-        }
-        secp256k1_pubkey_sort(CTX, pk_ptr, 5);
-        for (j = 1; j < 5; j++) {
-            secp256k1_pubkey_sort_cmp_data cmp_data;
-            cmp_data.ctx = CTX;
-            CHECK(secp256k1_pubkey_sort_cmp(&pk_ptr[j - 1], &pk_ptr[j], &cmp_data) <= 0);
-        }
-    }
-}
-
-/* Test vectors from BIP-MuSig2 */
-static void test_sort_vectors(void) {
-    enum { N_PUBKEYS = 6 };
-    unsigned char pk_ser[N_PUBKEYS][33] = {
-        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
-          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
-          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xB8 },
-        { 0x02, 0xF9, 0x30, 0x8A, 0x01, 0x92, 0x58, 0xC3, 0x10, 0x49, 0x34,
-          0x4F, 0x85, 0xF8, 0x9D, 0x52, 0x29, 0xB5, 0x31, 0xC8, 0x45, 0x83,
-          0x6F, 0x99, 0xB0, 0x86, 0x01, 0xF1, 0x13, 0xBC, 0xE0, 0x36, 0xF9 },
-        { 0x03, 0xDF, 0xF1, 0xD7, 0x7F, 0x2A, 0x67, 0x1C, 0x5F, 0x36, 0x18,
-          0x37, 0x26, 0xDB, 0x23, 0x41, 0xBE, 0x58, 0xFE, 0xAE, 0x1D, 0xA2,
-          0xDE, 0xCE, 0xD8, 0x43, 0x24, 0x0F, 0x7B, 0x50, 0x2B, 0xA6, 0x59 },
-        { 0x02, 0x35, 0x90, 0xA9, 0x4E, 0x76, 0x8F, 0x8E, 0x18, 0x15, 0xC2,
-          0xF2, 0x4B, 0x4D, 0x80, 0xA8, 0xE3, 0x14, 0x93, 0x16, 0xC3, 0x51,
-          0x8C, 0xE7, 0xB7, 0xAD, 0x33, 0x83, 0x68, 0xD0, 0x38, 0xCA, 0x66 },
-        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
-          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
-          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xFF },
-        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
-          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
-          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xB8 }
-    };
-    secp256k1_pubkey pubkeys[N_PUBKEYS];
-    secp256k1_pubkey *sorted[N_PUBKEYS];
-    const secp256k1_pubkey *pks_ptr[N_PUBKEYS];
-    int i;
-
-    sorted[0] = &pubkeys[3];
-    sorted[1] = &pubkeys[0];
-    sorted[2] = &pubkeys[0];
-    sorted[3] = &pubkeys[4];
-    sorted[4] = &pubkeys[1];
-    sorted[5] = &pubkeys[2];
-
-    for (i = 0; i < N_PUBKEYS; i++) {
-        CHECK(secp256k1_ec_pubkey_parse(CTX, &pubkeys[i], pk_ser[i], sizeof(pk_ser[i])));
-        pks_ptr[i] = &pubkeys[i];
-    }
-    CHECK(secp256k1_pubkey_sort(CTX, pks_ptr, N_PUBKEYS) == 1);
-    for (i = 0; i < N_PUBKEYS; i++) {
-        CHECK(secp256k1_memcmp_var(pks_ptr[i], sorted[i], sizeof(secp256k1_pubkey)) == 0);
-    }
-}
-
 static void run_extrakeys_tests(void) {
     /* xonly key test cases */
     test_xonly_pubkey();
@@ -668,11 +478,6 @@ static void run_extrakeys_tests(void) {
     /* keypair tests */
     test_keypair();
     test_keypair_add();
-
-    test_hsort();
-    test_sort_api();
-    test_sort();
-    test_sort_vectors();
 }
 
 #endif
diff --git a/src/secp256k1.c b/src/secp256k1.c
index 4c5782693..d6cdd0a02 100644
--- a/src/secp256k1.c
+++ b/src/secp256k1.c
@@ -37,6 +37,7 @@
 #include "int128_impl.h"
 #include "scratch_impl.h"
 #include "selftest.h"
+#include "hsort_impl.h"
 
 #ifdef SECP256K1_NO_BUILD
 # error "secp256k1.h processed without SECP256K1_BUILD defined while building secp256k1.c"
@@ -334,6 +335,34 @@ int secp256k1_ec_pubkey_cmp(const secp256k1_context* ctx, const secp256k1_pubkey
     return secp256k1_memcmp_var(out[0], out[1], sizeof(out[0]));
 }
 
+static int secp256k1_ec_pubkey_sort_cmp(const void* pk1, const void* pk2, void *ctx) {
+    return secp256k1_ec_pubkey_cmp((secp256k1_context *)ctx,
+                                     *(secp256k1_pubkey **)pk1,
+                                     *(secp256k1_pubkey **)pk2);
+}
+
+int secp256k1_ec_pubkey_sort(const secp256k1_context* ctx, const secp256k1_pubkey **pubkeys, size_t n_pubkeys) {
+    VERIFY_CHECK(ctx != NULL);
+    ARG_CHECK(pubkeys != NULL);
+
+    /* Suppress wrong warning (fixed in MSVC 19.33) */
+    #if defined(_MSC_VER) && (_MSC_VER < 1933)
+    #pragma warning(push)
+    #pragma warning(disable: 4090)
+    #endif
+
+    /* Casting away const is fine because neither secp256k1_hsort nor
+     * secp256k1_ec_pubkey_sort_cmp modify the data pointed to by the cmp_data
+     * argument. */
+    secp256k1_hsort(pubkeys, n_pubkeys, sizeof(*pubkeys), secp256k1_ec_pubkey_sort_cmp, (void *)ctx);
+
+    #if defined(_MSC_VER) && (_MSC_VER < 1933)
+    #pragma warning(pop)
+    #endif
+
+    return 1;
+}
+
 static void secp256k1_ecdsa_signature_load(const secp256k1_context* ctx, secp256k1_scalar* r, secp256k1_scalar* s, const secp256k1_ecdsa_signature* sig) {
     (void)ctx;
     if (sizeof(secp256k1_scalar) == 32) {
diff --git a/src/tests.c b/src/tests.c
index 8a10fdda9..0d57ab25e 100644
--- a/src/tests.c
+++ b/src/tests.c
@@ -3732,6 +3732,78 @@ static void run_inverse_tests(void)
     }
 }
 
+/***** HSORT TESTS *****/
+
+static void test_heap_swap(void) {
+    unsigned char a[600];
+    unsigned char e[sizeof(a)];
+    memset(a,       21, 200);
+    memset(a + 200, 99, 200);
+    memset(a + 400, 42, 200);
+    memset(e,       42, 200);
+    memset(e + 200, 99, 200);
+    memset(e + 400, 21, 200);
+    secp256k1_heap_swap(a, 0, 2, 200);
+    CHECK(secp256k1_memcmp_var(a, e, sizeof(a)) == 0);
+}
+
+static void test_hsort_is_sorted(unsigned char *elements, size_t n, size_t len) {
+    size_t i;
+    for (i = 1; i < n; i++) {
+        CHECK(secp256k1_memcmp_var(&elements[(i-1) * len], &elements[i * len], len) <= 0);
+    }
+}
+
+struct test_hsort_cmp_data {
+    size_t counter;
+    size_t element_len;
+};
+
+
+static int test_hsort_cmp(const void *ele1, const void *ele2, void *data) {
+  struct test_hsort_cmp_data *d = (struct test_hsort_cmp_data *) data;
+    d->counter += 1;
+    return secp256k1_memcmp_var((unsigned char *)ele1, (unsigned char *)ele2, d->element_len);
+}
+
+#define NUM 65
+#define MAX_ELEMENT_LEN 65
+static void test_hsort(size_t element_len) {
+    unsigned char elements[NUM * MAX_ELEMENT_LEN] = { 0 };
+    struct test_hsort_cmp_data data;
+    int i;
+
+    VERIFY_CHECK(element_len <= MAX_ELEMENT_LEN);
+    data.counter = 0;
+    data.element_len = element_len;
+
+    secp256k1_hsort(elements, 0, element_len, test_hsort_cmp, &data);
+    CHECK(data.counter == 0);
+    secp256k1_hsort(elements, 1, element_len, test_hsort_cmp, &data);
+    CHECK(data.counter == 0);
+    secp256k1_hsort(elements, NUM, element_len, test_hsort_cmp, &data);
+    CHECK(data.counter >= NUM - 1);
+    test_hsort_is_sorted(elements, NUM, element_len);
+
+    /* Test hsort with array of random length n */
+    for (i = 0; i < COUNT; i++) {
+        int n = secp256k1_testrand_int(NUM);
+        secp256k1_testrand_bytes_test(elements, n*element_len);
+        secp256k1_hsort(elements, n, element_len, test_hsort_cmp, &data);
+        test_hsort_is_sorted(elements, n, element_len);
+    }
+}
+#undef NUM
+#undef MAX_ELEMENT_LEN
+
+
+static void run_hsort_tests(void) {
+    test_heap_swap();
+    test_hsort(1);
+    test_hsort(64);
+    test_hsort(65);
+}
+
 /***** GROUP TESTS *****/
 
 /* This compares jacobian points including their Z, not just their geometric meaning. */
@@ -6806,6 +6878,161 @@ static void run_pubkey_comparison(void) {
     CHECK(secp256k1_ec_pubkey_cmp(CTX, &pk2, &pk1) > 0);
 }
 
+static void test_sort_helper(secp256k1_pubkey *pk, size_t *pk_order, size_t n_pk) {
+    size_t i;
+    const secp256k1_pubkey *pk_test[5];
+
+    for (i = 0; i < n_pk; i++) {
+        pk_test[i] = &pk[pk_order[i]];
+    }
+    secp256k1_ec_pubkey_sort(CTX, pk_test, n_pk);
+    for (i = 0; i < n_pk; i++) {
+        CHECK(secp256k1_memcmp_var(pk_test[i], &pk[i], sizeof(*pk_test[i])) == 0);
+    }
+}
+
+static void permute(size_t *arr, size_t n) {
+    size_t i;
+    for (i = n - 1; i >= 1; i--) {
+        size_t tmp, j;
+        j = secp256k1_testrand_int(i + 1);
+        tmp = arr[i];
+        arr[i] = arr[j];
+        arr[j] = tmp;
+    }
+}
+
+static void rand_pk(secp256k1_pubkey *pk) {
+    unsigned char seckey[32];
+    secp256k1_keypair keypair;
+    secp256k1_testrand256(seckey);
+    CHECK(secp256k1_keypair_create(CTX, &keypair, seckey) == 1);
+    CHECK(secp256k1_keypair_pub(CTX, pk, &keypair) == 1);
+}
+
+static void test_sort_api(void) {
+    secp256k1_pubkey pks[2];
+    const secp256k1_pubkey *pks_ptr[2];
+
+    pks_ptr[0] = &pks[0];
+    pks_ptr[1] = &pks[1];
+
+    rand_pk(&pks[0]);
+    rand_pk(&pks[1]);
+
+    CHECK(secp256k1_ec_pubkey_sort(CTX, pks_ptr, 2) == 1);
+    CHECK_ILLEGAL(CTX, secp256k1_ec_pubkey_sort(CTX, NULL, 2));
+    CHECK(secp256k1_ec_pubkey_sort(CTX, pks_ptr, 0) == 1);
+    /* Test illegal public keys */
+    memset(&pks[0], 0, sizeof(pks[0]));
+    CHECK_ILLEGAL_VOID(CTX, CHECK(secp256k1_ec_pubkey_sort(CTX, pks_ptr, 2) == 1));
+    memset(&pks[1], 0, sizeof(pks[1]));
+    {
+        int32_t ecount = 0;
+        secp256k1_context_set_illegal_callback(CTX, counting_callback_fn, &ecount);
+        CHECK(secp256k1_ec_pubkey_sort(CTX, pks_ptr, 2) == 1);
+        CHECK(ecount == 2);
+        secp256k1_context_set_illegal_callback(CTX, NULL, NULL);
+    }
+}
+
+static void test_sort(void) {
+    secp256k1_pubkey pk[5];
+    unsigned char pk_ser[5][33] = {
+        { 0x02, 0x08 },
+        { 0x02, 0x0b },
+        { 0x02, 0x0c },
+        { 0x03, 0x05 },
+        { 0x03, 0x0a },
+    };
+    int i;
+    size_t pk_order[5] = { 0, 1, 2, 3, 4 };
+
+    for (i = 0; i < 5; i++) {
+        CHECK(secp256k1_ec_pubkey_parse(CTX, &pk[i], pk_ser[i], sizeof(pk_ser[i])));
+    }
+
+    permute(pk_order, 1);
+    test_sort_helper(pk, pk_order, 1);
+    permute(pk_order, 2);
+    test_sort_helper(pk, pk_order, 2);
+    permute(pk_order, 3);
+    test_sort_helper(pk, pk_order, 3);
+    for (i = 0; i < COUNT; i++) {
+        permute(pk_order, 4);
+        test_sort_helper(pk, pk_order, 4);
+    }
+    for (i = 0; i < COUNT; i++) {
+        permute(pk_order, 5);
+        test_sort_helper(pk, pk_order, 5);
+    }
+    /* Check that sorting also works for random pubkeys */
+    for (i = 0; i < COUNT; i++) {
+        int j;
+        const secp256k1_pubkey *pk_ptr[5];
+        for (j = 0; j < 5; j++) {
+            rand_pk(&pk[j]);
+            pk_ptr[j] = &pk[j];
+        }
+        secp256k1_ec_pubkey_sort(CTX, pk_ptr, 5);
+        for (j = 1; j < 5; j++) {
+            CHECK(secp256k1_ec_pubkey_sort_cmp(&pk_ptr[j - 1], &pk_ptr[j], CTX) <= 0);
+        }
+    }
+}
+
+/* Test vectors from BIP-MuSig2 */
+static void test_sort_vectors(void) {
+    enum { N_PUBKEYS = 6 };
+    unsigned char pk_ser[N_PUBKEYS][33] = {
+        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
+          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
+          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xB8 },
+        { 0x02, 0xF9, 0x30, 0x8A, 0x01, 0x92, 0x58, 0xC3, 0x10, 0x49, 0x34,
+          0x4F, 0x85, 0xF8, 0x9D, 0x52, 0x29, 0xB5, 0x31, 0xC8, 0x45, 0x83,
+          0x6F, 0x99, 0xB0, 0x86, 0x01, 0xF1, 0x13, 0xBC, 0xE0, 0x36, 0xF9 },
+        { 0x03, 0xDF, 0xF1, 0xD7, 0x7F, 0x2A, 0x67, 0x1C, 0x5F, 0x36, 0x18,
+          0x37, 0x26, 0xDB, 0x23, 0x41, 0xBE, 0x58, 0xFE, 0xAE, 0x1D, 0xA2,
+          0xDE, 0xCE, 0xD8, 0x43, 0x24, 0x0F, 0x7B, 0x50, 0x2B, 0xA6, 0x59 },
+        { 0x02, 0x35, 0x90, 0xA9, 0x4E, 0x76, 0x8F, 0x8E, 0x18, 0x15, 0xC2,
+          0xF2, 0x4B, 0x4D, 0x80, 0xA8, 0xE3, 0x14, 0x93, 0x16, 0xC3, 0x51,
+          0x8C, 0xE7, 0xB7, 0xAD, 0x33, 0x83, 0x68, 0xD0, 0x38, 0xCA, 0x66 },
+        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
+          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
+          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xFF },
+        { 0x02, 0xDD, 0x30, 0x8A, 0xFE, 0xC5, 0x77, 0x7E, 0x13, 0x12, 0x1F,
+          0xA7, 0x2B, 0x9C, 0xC1, 0xB7, 0xCC, 0x01, 0x39, 0x71, 0x53, 0x09,
+          0xB0, 0x86, 0xC9, 0x60, 0xE1, 0x8F, 0xD9, 0x69, 0x77, 0x4E, 0xB8 }
+    };
+    secp256k1_pubkey pubkeys[N_PUBKEYS];
+    secp256k1_pubkey *sorted[N_PUBKEYS];
+    const secp256k1_pubkey *pks_ptr[N_PUBKEYS];
+    int i;
+
+    sorted[0] = &pubkeys[3];
+    sorted[1] = &pubkeys[0];
+    sorted[2] = &pubkeys[0];
+    sorted[3] = &pubkeys[4];
+    sorted[4] = &pubkeys[1];
+    sorted[5] = &pubkeys[2];
+
+    for (i = 0; i < N_PUBKEYS; i++) {
+        CHECK(secp256k1_ec_pubkey_parse(CTX, &pubkeys[i], pk_ser[i], sizeof(pk_ser[i])));
+        pks_ptr[i] = &pubkeys[i];
+    }
+    CHECK(secp256k1_ec_pubkey_sort(CTX, pks_ptr, N_PUBKEYS) == 1);
+    for (i = 0; i < N_PUBKEYS; i++) {
+        CHECK(secp256k1_memcmp_var(pks_ptr[i], sorted[i], sizeof(secp256k1_pubkey)) == 0);
+    }
+}
+
+static void run_pubkey_sort(void) {
+    test_sort_api();
+    test_sort();
+    test_sort_vectors();
+}
+
+
 static void run_random_pubkeys(void) {
     int i;
     for (i = 0; i < 10*COUNT; i++) {
@@ -7804,6 +8031,9 @@ int main(int argc, char **argv) {
     run_modinv_tests();
     run_inverse_tests();
 
+    /* sorting tests */
+    run_hsort_tests();
+
     /* hash tests */
     run_sha256_known_output_tests();
     run_sha256_counter_tests();
@@ -7873,6 +8103,7 @@ int main(int argc, char **argv) {
     /* ecdsa tests */
     run_ec_illegal_argument_tests();
     run_pubkey_comparison();
+    run_pubkey_sort();
     run_random_pubkeys();
     run_ecdsa_der_parse();
     run_ecdsa_sign_verify();