diff --git a/.github/workflows/atecc608-sim.yml b/.github/workflows/atecc608-sim.yml
index ea283e7268..f3768a1b6c 100644
--- a/.github/workflows/atecc608-sim.yml
+++ b/.github/workflows/atecc608-sim.yml
@@ -68,6 +68,11 @@ jobs:
           sed -i "/^RUN python3 - <<'PY'$/,/^PY$/d" Dockerfile.wolfcrypt
           ! grep -q "RUN python3 - <<'PY'" Dockerfile.wolfcrypt
 
+          # The simulator Dockerfile predates the new configure contract where
+          # --with-cryptoauthlib must be paired with --enable-microchip=<dev>.
+          sed -i 's/--with-cryptoauthlib=\/usr \\/--enable-microchip=608 \\\n        --with-cryptoauthlib=\/usr \\/' Dockerfile.wolfcrypt
+          grep -q -- '--enable-microchip=608' Dockerfile.wolfcrypt
+
       - uses: docker/setup-buildx-action@v3
 
       - name: Build wolfCrypt-ATECC608 test image
diff --git a/wolfcrypt/src/port/atmel/atmel.c b/wolfcrypt/src/port/atmel/atmel.c
index 233a8c5ca8..e9156ee13d 100644
--- a/wolfcrypt/src/port/atmel/atmel.c
+++ b/wolfcrypt/src/port/atmel/atmel.c
@@ -157,6 +157,20 @@ static int ateccx08a_cfg_initialized = 0;
         .rx_retries = 20,
     },
 #endif
+#if !defined(WOLFSSL_MANUALLY_SELECT_DEVICE_CONFIG) && \
+    !(defined(WOLFSSL_ATECC608A) && defined(MICROCHIP_MPLAB_HARMONY_3)) && \
+    !defined(ATCA_HAL_SPI) && !defined(ATCA_HAL_I2C)
+    {
+        /* Custom HAL users provide callbacks later through
+         * wolfCrypt_ATECC_SetConfig(), but gCfg still needs a valid default
+         * backing object so configure-time warning builds do not see an empty
+         * config array. */
+        .iface_type = ATCA_CUSTOM_IFACE,
+        .devtype    = MICROCHIP_DEV_TYPE,
+        .wake_delay = 1500,
+        .rx_retries = 20,
+    },
+#endif
 };
 static ATCAIfaceCfg* gCfg = &config_atmel_device[WOLFSSL_ATCA_DEVICE_NO];
 
diff --git a/wolfcrypt/test/test.c b/wolfcrypt/test/test.c
index ac01e0d9ce..2790c70636 100644
--- a/wolfcrypt/test/test.c
+++ b/wolfcrypt/test/test.c
@@ -26131,13 +26131,15 @@ static wc_test_ret_t rsa_keygen_test(WC_RNG* rng)
     !defined(WOLFSSL_MICROCHIP)
     word32 idx = 0;
 #endif
-    int    derSz = 0;
 #if !defined(WOLFSSL_SP_MATH) && !defined(HAVE_FIPS) && \
     (defined(RSA_MIN_SIZE) && (RSA_MIN_SIZE <= 1024))
     int    keySz = 1024;
 #else
     int    keySz = 2048;
 #endif
+#if !defined(WC_TEST_SKIP_RSA_PRIVATE_EXPORT) && !defined(WOLFSSL_MICROCHIP)
+    int    derSz = 0;
+#endif
 
 #ifdef WOLF_CRYPTO_CB_ONLY_RSA
     if (devId == INVALID_DEVID) {
@@ -26180,6 +26182,7 @@ static wc_test_ret_t rsa_keygen_test(WC_RNG* rng)
     if (ret != 0)
         ERROR_OUT(WC_TEST_RET_ENC_EC(ret), exit_rsa);
 #endif
+#if !defined(WC_TEST_SKIP_RSA_PRIVATE_EXPORT) && !defined(WOLFSSL_MICROCHIP)
 #ifndef WOLFSSL_NO_MALLOC
     der = (byte*)XMALLOC(FOURK_BUF, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
     if (der == NULL) {
@@ -26189,7 +26192,6 @@ static wc_test_ret_t rsa_keygen_test(WC_RNG* rng)
 #else
     derSz = sizeof(der);
 #endif
-#if !defined(WC_TEST_SKIP_RSA_PRIVATE_EXPORT) && !defined(WOLFSSL_MICROCHIP)
     derSz = wc_RsaKeyToDer(genKey, der, derSz);
     if (derSz < 0) {
         ERROR_OUT(WC_TEST_RET_ENC_EC(derSz), exit_rsa);