diff --git a/PKG-INFO b/PKG-INFO
index ddd9d07bf0c0d35cfe3a999bf15e7ea679f38430..1e576e097085ab70cb60af46b3223716af07c6f4 100644
--- a/PKG-INFO
+++ b/PKG-INFO
@@ -1,13 +1,13 @@
 Metadata-Version: 2.1
 Name: swh.model
-Version: 0.0.50
+Version: 0.0.51
 Summary: Software Heritage data model
 Home-page: https://forge.softwareheritage.org/diffusion/DMOD/
 Author: Software Heritage developers
 Author-email: swh-devel@inria.fr
 License: UNKNOWN
-Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Source, https://forge.softwareheritage.org/source/swh-model
+Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Funding, https://www.softwareheritage.org/donate
 Description: swh-model
         =========
diff --git a/swh.model.egg-info/PKG-INFO b/swh.model.egg-info/PKG-INFO
index ddd9d07bf0c0d35cfe3a999bf15e7ea679f38430..1e576e097085ab70cb60af46b3223716af07c6f4 100644
--- a/swh.model.egg-info/PKG-INFO
+++ b/swh.model.egg-info/PKG-INFO
@@ -1,13 +1,13 @@
 Metadata-Version: 2.1
 Name: swh.model
-Version: 0.0.50
+Version: 0.0.51
 Summary: Software Heritage data model
 Home-page: https://forge.softwareheritage.org/diffusion/DMOD/
 Author: Software Heritage developers
 Author-email: swh-devel@inria.fr
 License: UNKNOWN
-Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Source, https://forge.softwareheritage.org/source/swh-model
+Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Funding, https://www.softwareheritage.org/donate
 Description: swh-model
         =========
diff --git a/swh/model/hypothesis_strategies.py b/swh/model/hypothesis_strategies.py
index ca568ee7e909421192f1cb9ae62111ca86ea5670..e9acfa1e71305105353f3564a693714598e7ec6e 100644
--- a/swh/model/hypothesis_strategies.py
+++ b/swh/model/hypothesis_strategies.py
@@ -79,7 +79,7 @@ def origin_visits():
     return builds(
         OriginVisit,
         visit=integers(0, 1000),
-        origin=origins(),
+        origin=urls(),
         status=sampled_from(['ongoing', 'full', 'partial']),
         type=pgsql_text())
 
diff --git a/swh/model/model.py b/swh/model/model.py
index baf4f54110b860e6967de9871065a747acd0a9e7..8c31f6d67989c148f0fb3f71d020942084487046 100644
--- a/swh/model/model.py
+++ b/swh/model/model.py
@@ -121,7 +121,7 @@ class Origin(BaseModel):
 class OriginVisit(BaseModel):
     """Represents a visit of an origin at a given point in time, by a
     SWH loader."""
-    origin = attr.ib(type=Origin)
+    origin = attr.ib(type=str)
     date = attr.ib(type=datetime.datetime)
     status = attr.ib(
         type=str,
@@ -149,7 +149,6 @@ class OriginVisit(BaseModel):
         d = d.copy()
         date = d.pop('date')
         return cls(
-            origin=Origin.from_dict(d.pop('origin')),
             date=(date
                   if isinstance(date, datetime.datetime)
                   else dateutil.parser.parse(date)),
diff --git a/swh/model/tests/test_model.py b/swh/model/tests/test_model.py
index 2900cd1f9fd6862a4bbd605e1e51fccec50cc6b6..f65dd28dade21f6c2dc9cb085f2f6fbecb613883 100644
--- a/swh/model/tests/test_model.py
+++ b/swh/model/tests/test_model.py
@@ -3,7 +3,6 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
-import attr
 import copy
 
 from hypothesis import given
@@ -44,10 +43,7 @@ def test_todict_origins(origin):
 def test_todict_origin_visits(origin_visit):
     obj = origin_visit.to_dict()
 
-    assert 'type' not in obj['origin']
-    origin2 = attr.evolve(origin_visit.origin, type=None)
-    origin_visit2 = attr.evolve(origin_visit, origin=origin2)
-    assert origin_visit2 == type(origin_visit).from_dict(obj)
+    assert origin_visit == type(origin_visit).from_dict(obj)
 
 
 def test_content_get_hash():
diff --git a/version.txt b/version.txt
index 87d9c2b83fa7ea845ba38cd3d2faa3a4130d640a..c025c3f0a5a3764b78e86c109a712a11cf3f7339 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-v0.0.50-0-gb064a0b
\ No newline at end of file
+v0.0.51-0-g0b9c5be
\ No newline at end of file