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diff --git a/src/secp256k1/examples/ecdsa.c b/src/secp256k1/examples/ecdsa.c
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+++ b/src/secp256k1/examples/ecdsa.c
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+/*************************************************************************
+ * Written in 2020-2022 by Elichai Turkel                                *
+ * To the extent possible under law, the author(s) have dedicated all    *
+ * copyright and related and neighboring rights to the software in this  *
+ * file to the public domain worldwide. This software is distributed     *
+ * without any warranty. For the CC0 Public Domain Dedication, see       *
+ * EXAMPLES_COPYING or https://creativecommons.org/publicdomain/zero/1.0 *
+ *************************************************************************/
+
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+
+#include <secp256k1.h>
+
+#include "examples_util.h"
+
+int main(void) {
+    /* Instead of signing the message directly, we must sign a 32-byte hash.
+     * Here the message is "Hello, world!" and the hash function was SHA-256.
+     * An actual implementation should just call SHA-256, but this example
+     * hardcodes the output to avoid depending on an additional library.
+     * See https://bitcoin.stackexchange.com/questions/81115/if-someone-wanted-to-pretend-to-be-satoshi-by-posting-a-fake-signature-to-defrau/81116#81116 */
+    unsigned char msg_hash[32] = {
+        0x31, 0x5F, 0x5B, 0xDB, 0x76, 0xD0, 0x78, 0xC4,
+        0x3B, 0x8A, 0xC0, 0x06, 0x4E, 0x4A, 0x01, 0x64,
+        0x61, 0x2B, 0x1F, 0xCE, 0x77, 0xC8, 0x69, 0x34,
+        0x5B, 0xFC, 0x94, 0xC7, 0x58, 0x94, 0xED, 0xD3,
+    };
+    unsigned char seckey[32];
+    unsigned char randomize[32];
+    unsigned char compressed_pubkey[33];
+    unsigned char serialized_signature[64];
+    size_t len;
+    int is_signature_valid, is_signature_valid2;
+    int return_val;
+    secp256k1_pubkey pubkey;
+    secp256k1_ecdsa_signature sig;
+    /* Before we can call actual API functions, we need to create a "context". */
+    secp256k1_context* ctx = secp256k1_context_create(SECP256K1_CONTEXT_NONE);
+    if (!fill_random(randomize, sizeof(randomize))) {
+        printf("Failed to generate randomness\n");
+        return 1;
+    }
+    /* Randomizing the context is recommended to protect against side-channel
+     * leakage See `secp256k1_context_randomize` in secp256k1.h for more
+     * information about it. This should never fail. */
+    return_val = secp256k1_context_randomize(ctx, randomize);
+    assert(return_val);
+
+    /*** Key Generation ***/
+
+    /* If the secret key is zero or out of range (bigger than secp256k1's
+     * order), we try to sample a new key. Note that the probability of this
+     * happening is negligible. */
+    while (1) {
+        if (!fill_random(seckey, sizeof(seckey))) {
+            printf("Failed to generate randomness\n");
+            return 1;
+        }
+        if (secp256k1_ec_seckey_verify(ctx, seckey)) {
+            break;
+        }
+    }
+
+    /* Public key creation using a valid context with a verified secret key should never fail */
+    return_val = secp256k1_ec_pubkey_create(ctx, &pubkey, seckey);
+    assert(return_val);
+
+    /* Serialize the pubkey in a compressed form(33 bytes). Should always return 1. */
+    len = sizeof(compressed_pubkey);
+    return_val = secp256k1_ec_pubkey_serialize(ctx, compressed_pubkey, &len, &pubkey, SECP256K1_EC_COMPRESSED);
+    assert(return_val);
+    /* Should be the same size as the size of the output, because we passed a 33 byte array. */
+    assert(len == sizeof(compressed_pubkey));
+
+    /*** Signing ***/
+
+    /* Generate an ECDSA signature `noncefp` and `ndata` allows you to pass a
+     * custom nonce function, passing `NULL` will use the RFC-6979 safe default.
+     * Signing with a valid context, verified secret key
+     * and the default nonce function should never fail. */
+    return_val = secp256k1_ecdsa_sign(ctx, &sig, msg_hash, seckey, NULL, NULL);
+    assert(return_val);
+
+    /* Serialize the signature in a compact form. Should always return 1
+     * according to the documentation in secp256k1.h. */
+    return_val = secp256k1_ecdsa_signature_serialize_compact(ctx, serialized_signature, &sig);
+    assert(return_val);
+
+
+    /*** Verification ***/
+
+    /* Deserialize the signature. This will return 0 if the signature can't be parsed correctly. */
+    if (!secp256k1_ecdsa_signature_parse_compact(ctx, &sig, serialized_signature)) {
+        printf("Failed parsing the signature\n");
+        return 1;
+    }
+
+    /* Deserialize the public key. This will return 0 if the public key can't be parsed correctly. */
+    if (!secp256k1_ec_pubkey_parse(ctx, &pubkey, compressed_pubkey, sizeof(compressed_pubkey))) {
+        printf("Failed parsing the public key\n");
+        return 1;
+    }
+
+    /* Verify a signature. This will return 1 if it's valid and 0 if it's not. */
+    is_signature_valid = secp256k1_ecdsa_verify(ctx, &sig, msg_hash, &pubkey);
+
+    printf("Is the signature valid? %s\n", is_signature_valid ? "true" : "false");
+    printf("Secret Key: ");
+    print_hex(seckey, sizeof(seckey));
+    printf("Public Key: ");
+    print_hex(compressed_pubkey, sizeof(compressed_pubkey));
+    printf("Signature: ");
+    print_hex(serialized_signature, sizeof(serialized_signature));
+
+    /* This will clear everything from the context and free the memory */
+    secp256k1_context_destroy(ctx);
+
+    /* Bonus example: if all we need is signature verification (and no key
+       generation or signing), we don't need to use a context created via
+       secp256k1_context_create(). We can simply use the static (i.e., global)
+       context secp256k1_context_static. See its description in
+       include/secp256k1.h for details. */
+    is_signature_valid2 = secp256k1_ecdsa_verify(secp256k1_context_static,
+                                                 &sig, msg_hash, &pubkey);
+    assert(is_signature_valid2 == is_signature_valid);
+
+    /* It's best practice to try to clear secrets from memory after using them.
+     * This is done because some bugs can allow an attacker to leak memory, for
+     * example through "out of bounds" array access (see Heartbleed), Or the OS
+     * swapping them to disk. Hence, we overwrite the secret key buffer with zeros.
+     *
+     * Here we are preventing these writes from being optimized out, as any good compiler
+     * will remove any writes that aren't used. */
+    secure_erase(seckey, sizeof(seckey));
+
+    return 0;
+}