diff --git a/app/config.ini b/app/config.ini
index 5a97d75..8b14dfc 100644
--- a/app/config.ini
+++ b/app/config.ini
@@ -14,6 +14,9 @@ keypair = /app/app/ci_keypair.keys
 contracts_path = /app/app/contracts/src
 
 
+secret = 615872afdb35a291f56166d63399d0fa1f2a37415b24206fb051dbce294afc5c
+
+
 # OAuth2
 ALGORITHM = HS256
 TOKEN_SUBJECT = access
diff --git a/app/models.py b/app/models.py
index c6b6b67..0377a5e 100644
--- a/app/models.py
+++ b/app/models.py
@@ -97,6 +97,10 @@ def exists(cls, aaid, value):
     def total(cls):
         return DBSession.query(cls).count()
 
+    @classmethod
+    def total_by_aaid(cls, aaid):
+        return DBSession.query(cls).filter_by(aaid=aaid).count()
+
 
 class Statistics(Base):
     uid = Column(Integer, primary_key=True, index=True)
@@ -128,6 +132,26 @@ def aggregate(cls):
 
         return result
 
+    @classmethod
+    def by_aa(cls, aa):
+        result = {}
+        values = (
+            DBSession.query(cls.name, cls.value, func.count(cls.value), cls.aaid)
+            .filter_by(aaid=aa.authorizable_attribute_id)
+            .group_by(cls.name, cls.value)
+            .all()
+        )
+        for v in values:
+            existent_list = result.get(v[0], [])
+            existent_list.append({v[1]: v[2]})
+            if v[2] >= aa.optional_k(v[0]):
+                result[v[0]] = existent_list
+        result["total"] = ValidatedCredentials.total_by_aaid(
+            aa.authorizable_attribute_id
+        )
+
+        return result
+
 
 Base.metadata.create_all(bind=engine)
 
diff --git a/app/routers/authorizable_attribute.py b/app/routers/authorizable_attribute.py
index a674eb4..435b294 100644
--- a/app/routers/authorizable_attribute.py
+++ b/app/routers/authorizable_attribute.py
@@ -67,9 +67,11 @@ def authorizable_attribute(
 ):
     info = [_.json() for _ in item.authorizable_attribute_info]
     optional = [_.json() for _ in item.authorizable_attribute_info_optional]
-    keypair = ZenContract(
+
+    keypair_contract = ZenContract(
         CONTRACTS.GENERATE_KEYPAIR, {"issuer_identifier": config.get("uid")}
-    ).execute()
+    )
+    keypair = keypair_contract.execute()
     contract = ZenContract(
         CONTRACTS.PUBLIC_VERIFY, {"issuer_identifier": config.get("uid")}
     )
diff --git a/app/routers/security.py b/app/routers/security.py
index 5543017..863bc8d 100644
--- a/app/routers/security.py
+++ b/app/routers/security.py
@@ -1,6 +1,4 @@
-import json
 from datetime import timedelta, datetime
-from pathlib import Path
 
 import jwt
 from fastapi import Depends, HTTPException, APIRouter
@@ -8,32 +6,12 @@
 
 from app.config.config import BaseConfig
 from app.schema import TokenOutput
-from app.zencontract import ZenContract, CONTRACTS
 
 router = APIRouter()
 config = BaseConfig()
 log = config.logger
 
 
-def load_keypair():
-    keypair = Path(config.get("keypair"))
-    if not keypair.is_file():
-        log.info("CREATING KEYPAIR IN %s" % keypair.as_posix())
-        keypair.touch()
-        keypair.write_text(
-            ZenContract(
-                CONTRACTS.GENERATE_KEYPAIR, {"issuer_identifier": config.get("uid")}
-            ).execute()
-        )
-
-    if config.getboolean("debug"):  # pragma: no cover
-        log.debug("+" * 50)
-        log.debug("KEYPAIR IS: \n%s" % keypair.read_text())
-        log.debug("+" * 50)
-
-    return keypair.read_text()
-
-
 def create_access_token(*, data: dict, expires_delta: timedelta = None):
     to_encode = data.copy()
     if expires_delta:
@@ -43,8 +21,7 @@ def create_access_token(*, data: dict, expires_delta: timedelta = None):
             minutes=config.getint("ACCESS_TOKEN_EXPIRE_MINUTES")
         )
     to_encode.update({"exp": expire, "sub": config.get("TOKEN_SUBJECT")})
-    keypair = json.loads(load_keypair())
-    secret = keypair[config.get("uid")]["sign"]["x"]
+    secret = config.get("secret")
     encoded_jwt = jwt.encode(to_encode, secret, algorithm=config.get("ALGORITHM"))
     return encoded_jwt
 
diff --git a/app/routers/stats.py b/app/routers/stats.py
index 9666e81..3a6c18e 100644
--- a/app/routers/stats.py
+++ b/app/routers/stats.py
@@ -1,6 +1,7 @@
-from fastapi import APIRouter
+from fastapi import APIRouter, HTTPException
+from starlette.status import HTTP_204_NO_CONTENT
 
-from app.models import Statistics
+from app.models import Statistics, AuthorizableAttribute
 
 router = APIRouter()
 
@@ -12,3 +13,18 @@
 )
 def index():
     return Statistics.aggregate()
+
+
+@router.get(
+    "/{authorizable_attribute_id}",
+    summary="Get an aggregated view of optional info values, for an Authorizable Attribute",
+    tags=["Statistics"],
+)
+def get_authorizable_attribute_stats(authorizable_attribute_id):
+    aa = AuthorizableAttribute.by_aa_id(authorizable_attribute_id)
+    if not aa:
+        raise HTTPException(
+            status_code=HTTP_204_NO_CONTENT, detail="Authorizable Attribute Not Found"
+        )
+
+    return Statistics.by_aa(aa)
diff --git a/app/test.ini b/app/test.ini
index a295be1..75cce02 100644
--- a/app/test.ini
+++ b/app/test.ini
@@ -1,8 +1,9 @@
 [DEFAULT]
 debug = true
-uid = Credential Issuer 01
+uid = issuer_identifier
 keypair = /home/travis/build/DECODEproject/dddc-credential-issuer/tests/ci_keypair.keys
 contracts_path = /home/travis/build/DECODEproject/dddc-credential-issuer/app/contracts/src
+secret = 615872afdb35a291f56166d63399d0fa1f2a37415b24206fb051dbce294afc5c
 
 ALGORITHM = HS256
 TOKEN_SUBJECT = access
diff --git a/app/zencontract.py b/app/zencontract.py
index 594aa69..ec43e92 100644
--- a/app/zencontract.py
+++ b/app/zencontract.py
@@ -40,7 +40,7 @@ def get_contract(self):
         contract = contracts_dir.joinpath(self.name).read_text()
         for k, v in self.placeholder.items():
             contract = contract.replace(f"'{k}'", f"'{v}'")
-        return contract
+        return str(contract)
 
     def execute(self):
         if config.getboolean("debug"):  # pragma: no cover
@@ -50,11 +50,13 @@ def execute(self):
             log.debug("DATA: %s" % self._data)
             log.debug("KEYS: %s" % self._keys)
             log.debug("CODE: \n%s" % self.zencode)
-
-        result, errors = zenroom.zencode_exec(
-            script=self.zencode, keys=self._keys, data=self._data
-        )
-        self._error = errors
+        try:
+            result, errors = zenroom.zencode_exec(
+                script=self.zencode, keys=self._keys, data=self._data
+            )
+            self._error = str(errors)
+        except Exception:
+            log.exception("Zenroom contract exception", exc_info=True)
         return result
 
     def keys(self, keys=None):
diff --git a/setup.cfg b/setup.cfg
index 9dc95b4..2ab11d9 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -7,7 +7,6 @@ env =
     DDDC_CREDENTIAL_ISSUER_CONFIGFILE=/home/puria/src/dddc-credential-issuer/app/test.ini
 
 
-
 [flake8]
 ignore = E501
 max-line-length = 99
diff --git a/setup.py b/setup.py
index 1392c44..72c4ad1 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@
         "bunch==1.0.1",
         "fastapi==0.33.0",
         "pytest_runner==4.4",
-        "zenroom==1.0.5",
+        "zenroom==1.0.6",
         "pre-commit==1.17.0",
         "python-multipart==0.0.5",
         "pyjwt==1.7.1",
diff --git a/tests/test_auth_attributes.py b/tests/test_auth_attributes.py
index 1a3b5f6..67e434e 100644
--- a/tests/test_auth_attributes.py
+++ b/tests/test_auth_attributes.py
@@ -37,7 +37,7 @@ def test_authorizable_attribute(client):
     attrib = AuthorizableAttribute.by_aa_id(aaid)
     assert attrib is not None
     assert attrib.authorizable_attribute_id == aaid
-    assert r.json()["credential_issuer_id"] == "Credential Issuer 01"
+    assert r.json()["credential_issuer_id"] == "issuer_identifier"
     assert "super_long_key" in attrib.authorizable_attribute_info
 
 
diff --git a/tests/test_config.py b/tests/test_config.py
index 53e9a6c..0c5cb30 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -13,7 +13,7 @@ def test_config_base_logger():
 
 def test_config_get():
     config = BaseConfig()
-    assert config.get("uid") == "Credential Issuer 01"
+    assert config.get("uid") == "issuer_identifier"
 
 
 def test_config_getint():
diff --git a/tests/test_main.py b/tests/test_main.py
index ea9fe89..2a15a2a 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -7,7 +7,6 @@
 
 from app.config.config import BaseConfig
 from app.main import api
-from app.routers.security import load_keypair
 from app.zencontract import ZenContract, CONTRACTS
 
 
@@ -52,13 +51,6 @@ def remove_secret():
         secret.unlink()
 
 
-def test_secret_key_creation(remove_secret):
-    c = BaseConfig()
-    assert not Path(c.get("keypair")).is_file()
-    load_keypair()
-    assert Path(c.get("keypair")).is_file()
-
-
 def test_uid(client):
     config = BaseConfig()
     r = client.get("/uid")