diff --git a/pico-keys-sdk b/pico-keys-sdk
index e18f192..71af710 160000
--- a/pico-keys-sdk
+++ b/pico-keys-sdk
@@ -1 +1 @@
-Subproject commit e18f192edff7d3dccd325cedc6992da91254ca9d
+Subproject commit 71af7105689abebebbcb76cf744d63034ba2cdaf
diff --git a/src/fido/cbor.c b/src/fido/cbor.c
index 50f7f0f..6acc7b8 100644
--- a/src/fido/cbor.c
+++ b/src/fido/cbor.c
@@ -210,9 +210,11 @@ CborError COSE_key(mbedtls_ecp_keypair *key, CborEncoder *mapEncoderParent,
     else if (key->grp.id == MBEDTLS_ECP_DP_CURVE25519) {
         alg = FIDO2_ALG_ECDH_ES_HKDF_256;
     }
+#ifdef MBEDTLS_EDDSA_C
     else if (key->grp.id == MBEDTLS_ECP_DP_ED25519) {
         alg = FIDO2_ALG_EDDSA;
     }
+#endif
     return COSE_key_params(crv, alg, &key->grp, &key->Q, mapEncoderParent, mapEncoder);
 }
 CborError COSE_key_shared(mbedtls_ecdh_context *key,
diff --git a/src/fido/cbor_cred_mgmt.c b/src/fido/cbor_cred_mgmt.c
index b079258..5469326 100644
--- a/src/fido/cbor_cred_mgmt.c
+++ b/src/fido/cbor_cred_mgmt.c
@@ -243,11 +243,11 @@ int cbor_cred_mgmt(const uint8_t *data, size_t len) {
             CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
         }
 
-        mbedtls_ecdsa_context key;
-        mbedtls_ecdsa_init(&key);
+        mbedtls_ecp_keypair key;
+        mbedtls_ecp_keypair_init(&key);
         if (fido_load_key((int)cred.curve, cred.id.data, &key) != 0) {
             credential_free(&cred);
-            mbedtls_ecdsa_free(&key);
+            mbedtls_ecp_keypair_free(&key);
             CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
         }
 
@@ -335,7 +335,7 @@ int cbor_cred_mgmt(const uint8_t *data, size_t len) {
             CBOR_CHECK(cbor_encode_boolean(&mapEncoder, false));
         }
         credential_free(&cred);
-        mbedtls_ecdsa_free(&key);
+        mbedtls_ecp_keypair_free(&key);
     }
     else if (subcommand == 0x06) {
         if (credentialId.id.present == false) {
diff --git a/src/fido/cbor_get_assertion.c b/src/fido/cbor_get_assertion.c
index 5838bc9..c0fdecd 100644
--- a/src/fido/cbor_get_assertion.c
+++ b/src/fido/cbor_get_assertion.c
@@ -548,14 +548,14 @@ int cbor_get_assertion(const uint8_t *data, size_t len, bool next) {
     memcpy(pa, clientDataHash.data, clientDataHash.len);
     uint8_t hash[64] = {0}, sig[MBEDTLS_ECDSA_MAX_LEN] = {0};
     const mbedtls_md_info_t *md = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
-    mbedtls_ecdsa_context ekey;
-    mbedtls_ecdsa_init(&ekey);
+    mbedtls_ecp_keypair ekey;
+    mbedtls_ecp_keypair_init(&ekey);
     size_t olen = 0;
     if (selcred) {
         ret = fido_load_key((int)selcred->curve, selcred->id.data, &ekey);
         if (ret != 0) {
             if (derive_key(rp_id_hash, false, selcred->id.data, MBEDTLS_ECP_DP_SECP256R1, &ekey) != 0) {
-                mbedtls_ecdsa_free(&ekey);
+                mbedtls_ecp_keypair_free(&ekey);
                 CBOR_ERROR(CTAP1_ERR_OTHER);
             }
         }
@@ -565,17 +565,20 @@ int cbor_get_assertion(const uint8_t *data, size_t len, bool next) {
         else if (ekey.grp.id == MBEDTLS_ECP_DP_SECP521R1) {
             md = mbedtls_md_info_from_type(MBEDTLS_MD_SHA512);
         }
+#ifdef MBEDTLS_EDDSA_C
         else if (ekey.grp.id == MBEDTLS_ECP_DP_ED25519) {
             md = NULL;
         }
-        
+#endif
         if (md != NULL) {
             ret = mbedtls_md(md, aut_data, aut_data_len + clientDataHash.len, hash);
             ret = mbedtls_ecdsa_write_signature(&ekey, mbedtls_md_get_type(md), hash, mbedtls_md_get_size(md), sig, sizeof(sig), &olen, random_gen, NULL);
         }
+#ifdef MBEDTLS_EDDSA_C
         else {
             ret = mbedtls_eddsa_write_signature(&ekey, aut_data, aut_data_len + clientDataHash.len, sig, sizeof(sig), &olen, MBEDTLS_EDDSA_PURE, NULL, 0, random_gen, NULL);
         }
+#endif
     }
     else {
         // Bogus signature
diff --git a/src/fido/cbor_make_credential.c b/src/fido/cbor_make_credential.c
index 6fa52b6..b3ad957 100644
--- a/src/fido/cbor_make_credential.c
+++ b/src/fido/cbor_make_credential.c
@@ -221,12 +221,14 @@ int cbor_make_credential(const uint8_t *data, size_t len) {
             if (curve <= 0) {
                 curve = FIDO2_CURVE_P256K1;
             }
-        }        
+        }
+#ifdef MBEDTLS_EDDSA_C
         else if (pubKeyCredParams[i].alg == FIDO2_ALG_EDDSA) {
             if (curve <= 0) {
                 curve = FIDO2_CURVE_ED25519;
             }
         }
+#endif
         else if (pubKeyCredParams[i].alg <= FIDO2_ALG_RS256 && pubKeyCredParams[i].alg >= FIDO2_ALG_RS512) {
             // pass
         }
@@ -434,9 +436,11 @@ int cbor_make_credential(const uint8_t *data, size_t len) {
     else if (ekey.grp.id == MBEDTLS_ECP_DP_SECP521R1) {
         md = mbedtls_md_info_from_type(MBEDTLS_MD_SHA512);
     }
+#ifdef MBEDTLS_EDDSA_C
     else if (ekey.grp.id == MBEDTLS_ECP_DP_ED25519) {
         md = NULL;
     }
+#endif
     if (md != NULL) {
         ret = mbedtls_md(md, aut_data, aut_data_len + clientDataHash.len, hash);
     }
@@ -457,9 +461,11 @@ int cbor_make_credential(const uint8_t *data, size_t len) {
     if (md != NULL) {
         ret = mbedtls_ecdsa_write_signature(&ekey, mbedtls_md_get_type(md), hash, mbedtls_md_get_size(md), sig, sizeof(sig), &olen, random_gen, NULL);
     }
+#ifdef MBEDTLS_EDDSA_C
     else {
         ret = mbedtls_eddsa_write_signature(&ekey, aut_data, aut_data_len + clientDataHash.len, sig, sizeof(sig), &olen, MBEDTLS_EDDSA_PURE, NULL, 0, random_gen, NULL);
     }
+#endif
     mbedtls_ecp_keypair_free(&ekey);
     if (ret != 0) {
         CBOR_ERROR(CTAP2_ERR_PROCESSING);
diff --git a/src/fido/cmd_authenticate.c b/src/fido/cmd_authenticate.c
index 2e7808c..823dce7 100644
--- a/src/fido/cmd_authenticate.c
+++ b/src/fido/cmd_authenticate.c
@@ -38,8 +38,8 @@ int cmd_authenticate() {
         return SW_CONDITIONS_NOT_SATISFIED();
     }
 
-    mbedtls_ecdsa_context key;
-    mbedtls_ecdsa_init(&key);
+    mbedtls_ecp_keypair key;
+    mbedtls_ecp_keypair_init(&key);
     int ret = 0;
     uint8_t *tmp_kh = (uint8_t *) calloc(1, req->keyHandleLen);
     memcpy(tmp_kh, req->keyHandle, req->keyHandleLen);
@@ -49,18 +49,18 @@ int cmd_authenticate() {
     else {
         ret = derive_key(req->appId, false, req->keyHandle, MBEDTLS_ECP_DP_SECP256R1, &key);
         if (verify_key(req->appId, req->keyHandle, &key) != 0) {
-            mbedtls_ecdsa_free(&key);
+            mbedtls_ecp_keypair_free(&key);
             free(tmp_kh);
             return SW_INCORRECT_PARAMS();
         }
     }
     free(tmp_kh);
     if (ret != PICOKEY_OK) {
-        mbedtls_ecdsa_free(&key);
+        mbedtls_ecp_keypair_free(&key);
         return SW_EXEC_ERROR();
     }
     if (P1(apdu) == CTAP_AUTH_CHECK_ONLY) {
-        mbedtls_ecdsa_free(&key);
+        mbedtls_ecp_keypair_free(&key);
         return SW_CONDITIONS_NOT_SATISFIED();
     }
     resp->flags = 0;
@@ -74,12 +74,12 @@ int cmd_authenticate() {
     memcpy(sig_base + CTAP_APPID_SIZE + 1 + 4, req->chal, CTAP_CHAL_SIZE);
     ret = mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), sig_base, sizeof(sig_base), hash);
     if (ret != 0) {
-        mbedtls_ecdsa_free(&key);
+        mbedtls_ecp_keypair_free(&key);
         return SW_EXEC_ERROR();
     }
     size_t olen = 0;
     ret = mbedtls_ecdsa_write_signature(&key, MBEDTLS_MD_SHA256, hash, 32, (uint8_t *) resp->sig, CTAP_MAX_EC_SIG_SIZE, &olen, random_gen, NULL);
-    mbedtls_ecdsa_free(&key);
+    mbedtls_ecp_keypair_free(&key);
     if (ret != 0) {
         return SW_EXEC_ERROR();
     }
diff --git a/src/fido/fido.c b/src/fido/fido.c
index 9e11385..462112c 100644
--- a/src/fido/fido.c
+++ b/src/fido/fido.c
@@ -112,12 +112,14 @@ mbedtls_ecp_group_id fido_curve_to_mbedtls(int curve) {
     else if (curve == FIDO2_CURVE_X448) {
         return MBEDTLS_ECP_DP_CURVE448;
     }
+#ifdef MBEDTLS_EDDSA_C
     else if (curve == FIDO2_CURVE_ED25519) {
         return MBEDTLS_ECP_DP_ED25519;
     }
     else if (curve == FIDO2_CURVE_ED448) {
         return MBEDTLS_ECP_DP_ED448;
     }
+#endif
     return MBEDTLS_ECP_DP_NONE;
 }
 int mbedtls_curve_to_fido(mbedtls_ecp_group_id id) {
@@ -139,12 +141,14 @@ int mbedtls_curve_to_fido(mbedtls_ecp_group_id id) {
     else if (id == MBEDTLS_ECP_DP_CURVE448) {
         return FIDO2_CURVE_X448;
     }
+#ifdef MBEDTLS_EDDSA_C
     else if (id == MBEDTLS_ECP_DP_ED25519) {
         return FIDO2_CURVE_ED25519;
     }
     else if (id == MBEDTLS_ECP_DP_ED448) {
         return FIDO2_CURVE_ED448;
     }
+#endif
     return 0;
 }
 
@@ -292,9 +296,11 @@ int derive_key(const uint8_t *app_id, bool new_key, uint8_t *key_handle, int cur
         if (r != 0) {
             return r;
         }
+#ifdef MBEDTLS_EDDSA_C
         if (curve == MBEDTLS_ECP_DP_ED25519) {
             return mbedtls_ecp_point_edwards(&key->grp, &key->Q, &key->d, random_gen, NULL);
         }
+#endif
         return mbedtls_ecp_mul(&key->grp, &key->Q, &key->d, &key->grp.G, random_gen, NULL);
     }
     mbedtls_platform_zeroize(outk, sizeof(outk));
diff --git a/src/fido/fido.h b/src/fido/fido.h
index f29b953..656007a 100644
--- a/src/fido/fido.h
+++ b/src/fido/fido.h
@@ -28,7 +28,9 @@
 #endif
 
 #include "mbedtls/ecdsa.h"
+#ifdef MBEDTLS_EDDSA_C
 #include "mbedtls/eddsa.h"
+#endif
 #ifndef ENABLE_EMULATION
 #include "hid/ctap_hid.h"
 #else