diff --git a/.github/workflows/check-doc.yml b/.github/workflows/check-doc.yml
new file mode 100644
index 000000000..06dcf3769
--- /dev/null
+++ b/.github/workflows/check-doc.yml
@@ -0,0 +1,26 @@
+name: Check doc
+
+on:
+  push:
+    branches: [ 'master', 'stable-*' ]
+  pull_request:
+    branches: [ 'master', 'stable-*' ]
+
+jobs:
+
+  test_doc:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Python
+      uses: actions/setup-python@v4
+      with:
+        python-version: "3.11"
+        cache: 'pip'
+        cache-dependency-path: '**/pyproject.toml'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install tox
+    - name: Check we can generate documentation
+      run: tox -e docs
diff --git a/.github/workflows/dockerhub.yml b/.github/workflows/dockerhub.yml
index c8943b9d1..6c8a47b20 100644
--- a/.github/workflows/dockerhub.yml
+++ b/.github/workflows/dockerhub.yml
@@ -1,4 +1,4 @@
-name: CI to Docker Hub
+name: Docker build
 
 on:
   push:
@@ -18,7 +18,7 @@ jobs:
       - name: Test image # Checks we are able to run the container.
         run: docker compose -f docker-compose.test.yml run sut
 
-  build:
+  build_upload:
     runs-on: ubuntu-latest
     needs: test
     if: github.event_name != 'pull_request'
diff --git a/.github/workflows/test-docs.yml b/.github/workflows/lint-and-tests.yml
similarity index 68%
rename from .github/workflows/test-docs.yml
rename to .github/workflows/lint-and-tests.yml
index 372ca8ae5..23f71fdc5 100644
--- a/.github/workflows/test-docs.yml
+++ b/.github/workflows/lint-and-tests.yml
@@ -1,4 +1,4 @@
-name: Test & Docs
+name: Lint & unit tests
 
 on:
   push:
@@ -7,14 +7,31 @@ on:
     branches: [ 'master', 'stable-*' ]
 
 jobs:
-  build:
-
+  lint:
     runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up Python
+      uses: actions/setup-python@v4
+      with:
+        python-version: "3.11"
+        cache: 'pip'
+        cache-dependency-path: '**/pyproject.toml'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install tox
+    - name: Run Lint
+      run: tox -e lint
 
-    # Use postgresql and MariaDB versions of Debian buster
+  test:
+    # Dependency on linting to avoid running our expensive matrix test for nothing
+    needs: lint
+    runs-on: ubuntu-latest
+    # Use postgresql and MariaDB versions of Debian bookworm
     services:
       postgres:
-        image: postgres:11
+        image: postgres:15
         ports:
           - 5432:5432
         env:
@@ -24,7 +41,7 @@ jobs:
         options:
           --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
       mariadb:
-        image: mariadb:10.3
+        image: mariadb:10.11
         env:
           MARIADB_ROOT_PASSWORD: ihatemoney
           MARIADB_DATABASE: ihatemoney_ci
@@ -39,24 +56,29 @@ jobs:
         python-version: [3.7, 3.8, 3.9, "3.10", "3.11", "3.12"]
         dependencies: [normal]
         database: [sqlite]
-        # Test other databases only with one version of Python (Debian buster has 3.7)
+        # Installation breaks with python 3.12, see https://github.com/spiral-project/ihatemoney/issues/1297
+        exclude:
+          - python-version: "3.12"
+            dependencies: normal
+            database: sqlite
+        # Test other databases with only a few versions of Python (Debian bullseye has 3.9, bookworm has 3.11)
         include:
-          - python-version: 3.7
+          - python-version: 3.9
             dependencies: normal
             database: postgresql
-          - python-version: 3.7
+          - python-version: 3.9
+            dependencies: normal
+            database: mariadb
+          - python-version: 3.11
+            dependencies: normal
+            database: postgresql
+          - python-version: 3.11
             dependencies: normal
             database: mariadb
           # Try a few variants with the minimal versions supported
           - python-version: 3.7
             dependencies: minimal
             database: sqlite
-          - python-version: 3.7
-            dependencies: minimal
-            database: postgresql
-          - python-version: 3.7
-            dependencies: minimal
-            database: mariadb
           - python-version: 3.9
             dependencies: minimal
             database: sqlite
@@ -66,6 +88,12 @@ jobs:
           - python-version: "3.11"
             dependencies: minimal
             database: sqlite
+          - python-version: "3.11"
+            dependencies: minimal
+            database: postgresql
+          - python-version: "3.11"
+            dependencies: minimal
+            database: mariadb
           - python-version: "3.12"
             dependencies: minimal
             database: sqlite
@@ -101,6 +129,3 @@ jobs:
       if: matrix.database == 'mariadb'
       env:
         TESTING_SQLALCHEMY_DATABASE_URI: 'mysql+pymysql://root:ihatemoney@localhost:3306/ihatemoney_ci'
-    - name: Run Lint & Docs
-      run: tox -e lint_docs
-      if: matrix.python-version == '3.12'
diff --git a/ihatemoney/forms.py b/ihatemoney/forms.py
index 6a787e214..e1ddabe87 100644
--- a/ihatemoney/forms.py
+++ b/ihatemoney/forms.py
@@ -364,7 +364,12 @@ class BillForm(FlaskForm):
     payed_for = SelectMultipleField(
         _("For whom?"), validators=[DataRequired()], coerce=int
     )
-    bill_type = SelectField(_("Bill Type"), choices=BillType.choices(), coerce=BillType, default=BillType.EXPENSE)
+    bill_type = SelectField(
+        _("Bill Type"),
+        choices=BillType.choices(),
+        coerce=BillType,
+        default=BillType.EXPENSE,
+    )
     submit = SubmitField(_("Submit"))
     submit2 = SubmitField(_("Submit and add a new one"))
 
diff --git a/ihatemoney/migrations/versions/7a9b38559992_new_bill_type_attribute_added.py b/ihatemoney/migrations/versions/7a9b38559992_new_bill_type_attribute_added.py
index 9b1fc520b..d7e273306 100644
--- a/ihatemoney/migrations/versions/7a9b38559992_new_bill_type_attribute_added.py
+++ b/ihatemoney/migrations/versions/7a9b38559992_new_bill_type_attribute_added.py
@@ -19,7 +19,10 @@ def upgrade():
     billtype_enum = sa.Enum(BillType)
     billtype_enum.create(op.get_bind(), checkfirst=True)
 
-    op.add_column("bill", sa.Column("bill_type", billtype_enum, server_default=BillType.EXPENSE.name))
+    op.add_column(
+        "bill",
+        sa.Column("bill_type", billtype_enum, server_default=BillType.EXPENSE.name),
+    )
     op.add_column("bill_version", sa.Column("bill_type", sa.UnicodeText()))
 
 
@@ -28,4 +31,4 @@ def downgrade():
     op.drop_column("bill_version", "bill_type")
 
     billtype_enum = sa.Enum(BillType)
-    billtype_enum.drop(op.get_bind())
\ No newline at end of file
+    billtype_enum.drop(op.get_bind())
diff --git a/ihatemoney/models.py b/ihatemoney/models.py
index fcc172647..c7dee1856 100644
--- a/ihatemoney/models.py
+++ b/ihatemoney/models.py
@@ -1,6 +1,6 @@
 from collections import defaultdict
-from enum import Enum
 import datetime
+from enum import Enum
 import itertools
 
 from dateutil.parser import parse
@@ -22,7 +22,7 @@
 
 from ihatemoney.currency_convertor import CurrencyConverter
 from ihatemoney.monkeypath_continuum import PatchedTransactionFactory
-from ihatemoney.utils import generate_password_hash, get_members, same_bill, FormEnum
+from ihatemoney.utils import generate_password_hash, get_members, same_bill
 from ihatemoney.versioning import (
     ConditionalVersioningManager,
     LoggingMode,
@@ -51,6 +51,7 @@
     ],
 )
 
+
 class BillType(Enum):
     EXPENSE = "Expense"
     REIMBURSEMENT = "Reimbursement"
@@ -131,7 +132,9 @@ def full_balance(self):
             if bill.bill_type == BillType.EXPENSE:
                 should_receive[bill.payer.id] += bill.converted_amount
                 for ower in bill.owers:
-                    should_pay[ower.id] += (ower.weight * bill.converted_amount / total_weight)
+                    should_pay[ower.id] += (
+                        ower.weight * bill.converted_amount / total_weight
+                    )
 
             if bill.bill_type == BillType.REIMBURSEMENT:
                 should_receive[bill.payer.id] += bill.converted_amount
@@ -563,7 +566,7 @@ def create_demo_project():
             ("Alice", 20, ("Amina", "Alice"), "Beer !", "Expense"),
             ("Amina", 50, ("Amina", "Alice", "Georg"), "AMAP", "Expense"),
         )
-        for (payer, amount, owers, what, bill_type) in operations:
+        for payer, amount, owers, what, bill_type in operations:
             db.session.add(
                 Bill(
                     amount=amount,
diff --git a/ihatemoney/tests/api_test.py b/ihatemoney/tests/api_test.py
index ff94ebe7e..191790b64 100644
--- a/ihatemoney/tests/api_test.py
+++ b/ihatemoney/tests/api_test.py
@@ -1017,7 +1017,6 @@ def test_amount_too_high(self):
     def test_validate_bill_type(self):
         self.api_create("raclette")
         self.api_add_member("raclette", "zorglub")
-        
 
         req = self.client.post(
             "/api/projects/raclette/bills",
@@ -1029,7 +1028,7 @@ def test_validate_bill_type(self):
                 "bill_type": "wrong_bill_type",
                 "amount": "50",
             },
-            headers=self.get_auth("raclette")
+            headers=self.get_auth("raclette"),
         )
 
         self.assertStatus(400, req)
@@ -1044,7 +1043,7 @@ def test_validate_bill_type(self):
                 "bill_type": "Expense",
                 "amount": "50",
             },
-            headers=self.get_auth("raclette")
+            headers=self.get_auth("raclette"),
         )
 
         self.assertStatus(201, req)
@@ -1063,7 +1062,7 @@ def test_default_bill_type(self):
                 "payed_for": ["1"],
                 "amount": "50",
             },
-            headers=self.get_auth("raclette")
+            headers=self.get_auth("raclette"),
         )
 
         self.assertStatus(201, req)
@@ -1076,4 +1075,3 @@ def test_default_bill_type(self):
         # Bill type should now be "Expense"
         got = json.loads(req.data.decode("utf-8"))
         assert got["bill_type"] == "Expense"
-        
diff --git a/ihatemoney/tests/budget_test.py b/ihatemoney/tests/budget_test.py
index 9ddeec8a8..e64090b92 100644
--- a/ihatemoney/tests/budget_test.py
+++ b/ihatemoney/tests/budget_test.py
@@ -716,8 +716,8 @@ def test_manage_bills(self):
                 "amount": "17",
             },
         )
-        
-        #transfer bill should not affect balances at all
+
+        # transfer bill should not affect balances at all
         self.client.post(
             "/raclette/add",
             data={
@@ -801,22 +801,22 @@ def test_reimbursement_bill(self):
         self.client.post("/rent/members/add", data={"name": "alice"})
 
         members_ids = [m.id for m in self.get_project("rent").members]
-        # create a bill to test reimbursement 
+        # create a bill to test reimbursement
         self.client.post(
             "/rent/add",
             data={
                 "date": "2022-12-12",
                 "what": "december rent",
-                "payer": members_ids[0], #bob
-                "payed_for": members_ids, #bob and alice
+                "payer": members_ids[0],  # bob
+                "payed_for": members_ids,  # bob and alice
                 "bill_type": "Expense",
                 "amount": "1000",
             },
         )
-        #check balance 
+        # check balance
         balance = self.get_project("rent").balance
         assert set(balance.values()), set([500 == -500])
-        #check paid
+        # check paid
         bob_paid = self.get_project("rent").full_balance[2][members_ids[0]]
         alice_paid = self.get_project("rent").full_balance[2][members_ids[1]]
         assert bob_paid == 1000
@@ -828,8 +828,8 @@ def test_reimbursement_bill(self):
             data={
                 "date": "2022-12-13",
                 "what": "reimbursement for rent",
-                "payer": members_ids[1], #alice
-                "payed_for": members_ids[0], #bob  
+                "payer": members_ids[1],  # alice
+                "payed_for": members_ids[0],  # bob
                 "bill_type": "Reimbursement",
                 "amount": "500",
             },
@@ -837,94 +837,12 @@ def test_reimbursement_bill(self):
 
         balance = self.get_project("rent").balance
         assert set(balance.values()), set([0 == 0])
-        #check paid
+        # check paid
         bob_paid = self.get_project("rent").full_balance[2][members_ids[0]]
         alice_paid = self.get_project("rent").full_balance[2][members_ids[1]]
         assert bob_paid == 500
         assert alice_paid == 500
-    def test_transfer_bill(self):
-        self.post_project("random")
 
-        # add two participants
-        self.client.post("/random/members/add", data={"name": "zorglub"})
-        self.client.post("/random/members/add", data={"name": "fred"})
-
-        members_ids = [m.id for m in self.get_project("random").members]
-        self.client.post(
-            "/random/add",
-            data={
-                "date": "2022-10-10",
-                "what": "Rent",
-                "payer": members_ids[0], #zorglub
-                "payed_for": members_ids, #zorglub + fred  
-                "bill_type": "Expense",
-                "amount": "1000",
-            },
-        )
-        # test transfer bill (should not affect anything whatsoever)
-        self.client.post(
-            "/random/add",
-            data={
-                "date": "2022-10-10",
-                "what": "Transfer of 500 to fred",
-                "payer": members_ids[0], #zorglub
-                "payed_for": members_ids[1], #fred  
-                "bill_type": "Transfer",
-                "amount": "500",
-            },
-        )
-        balance = self.get_project("random").balance
-        assert set(balance.values()), set([500 == -500])
-
-    def test_reimbursement_bill(self):
-        self.post_project("rent")
-
-        # add two participants
-        self.client.post("/rent/members/add", data={"name": "bob"})
-        self.client.post("/rent/members/add", data={"name": "alice"})
-
-        members_ids = [m.id for m in self.get_project("rent").members]
-        # create a bill to test reimbursement 
-        self.client.post(
-            "/rent/add",
-            data={
-                "date": "2022-12-12",
-                "what": "december rent",
-                "payer": members_ids[0], #bob
-                "payed_for": members_ids, #bob and alice
-                "bill_type": "Expense",
-                "amount": "1000",
-            },
-        )
-        #check balance 
-        balance = self.get_project("rent").balance
-        assert set(balance.values()), set([500 == -500])
-        #check paid
-        bob_paid = self.get_project("rent").full_balance[2][members_ids[0]]
-        alice_paid = self.get_project("rent").full_balance[2][members_ids[1]]
-        assert bob_paid == 1000
-        assert alice_paid == 0
-
-        # test reimbursement bill
-        self.client.post(
-            "/rent/add",
-            data={
-                "date": "2022-12-13",
-                "what": "reimbursement for rent",
-                "payer": members_ids[1], #alice
-                "payed_for": members_ids[0], #bob  
-                "bill_type": "Reimbursement",
-                "amount": "500",
-            },
-        )
-
-        balance = self.get_project("rent").balance
-        assert set(balance.values()), set([0 == 0])
-        #check paid
-        bob_paid = self.get_project("rent").full_balance[2][members_ids[0]]
-        alice_paid = self.get_project("rent").full_balance[2][members_ids[1]]
-        assert bob_paid == 500
-        assert alice_paid == 500
     def test_transfer_bill(self):
         self.post_project("random")
 
@@ -938,8 +856,8 @@ def test_transfer_bill(self):
             data={
                 "date": "2022-10-10",
                 "what": "Rent",
-                "payer": members_ids[0], #zorglub
-                "payed_for": members_ids, #zorglub + fred  
+                "payer": members_ids[0],  # zorglub
+                "payed_for": members_ids,  # zorglub + fred
                 "bill_type": "Expense",
                 "amount": "1000",
             },
@@ -950,8 +868,8 @@ def test_transfer_bill(self):
             data={
                 "date": "2022-10-10",
                 "what": "Transfer of 500 to fred",
-                "payer": members_ids[0], #zorglub
-                "payed_for": members_ids[1], #fred  
+                "payer": members_ids[0],  # zorglub
+                "payed_for": members_ids[1],  # fred
                 "bill_type": "Transfer",
                 "amount": "500",
             },
@@ -1433,7 +1351,7 @@ def test_settle(self):
         for m, a in members.items():
             assert abs(a - balance[m.id]) < 0.01
         return
-    
+
     def test_settle_button(self):
         self.post_project("raclette")
 
@@ -1482,16 +1400,24 @@ def test_settle_button(self):
         )
         project = self.get_project("raclette")
         transactions = project.get_transactions_to_settle_bill()
-        
+
         count = 0
         for t in transactions:
-            count+=1
-            self.client.get("/raclette/settle"+"/"+str(t["amount"])+"/"+str(t["ower"].id)+"/"+str(t["receiver"].id))
+            count += 1
+            self.client.get(
+                "/raclette/settle"
+                + "/"
+                + str(t["amount"])
+                + "/"
+                + str(t["ower"].id)
+                + "/"
+                + str(t["receiver"].id)
+            )
             temp_transactions = project.get_transactions_to_settle_bill()
-            #test if the one has disappeared
-            assert len(temp_transactions) == len(transactions)-count
-        
-            #test if theres a new one with bill_type reimbursement
+            # test if the one has disappeared
+            assert len(temp_transactions) == len(transactions) - count
+
+            # test if theres a new one with bill_type reimbursement
             bill = project.get_newest_bill()
             assert bill.bill_type == models.BillType.REIMBURSEMENT
         return
@@ -2005,7 +1931,7 @@ def test_rss_feed(self):
                     "payed_for": [1, 2, 3],
                     "amount": "12",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
             self.client.post(
@@ -2017,7 +1943,7 @@ def test_rss_feed(self):
                     "payed_for": [1, 2],
                     "amount": "15",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
             self.client.post(
@@ -2029,7 +1955,7 @@ def test_rss_feed(self):
                     "payed_for": [1, 2],
                     "amount": "10",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
 
@@ -2092,7 +2018,7 @@ def test_rss_feed_history_disabled(self):
                     "payed_for": [1, 2, 3],
                     "amount": "12",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
             self.client.post(
@@ -2104,7 +2030,7 @@ def test_rss_feed_history_disabled(self):
                     "payed_for": [1, 2],
                     "amount": "15",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
             self.client.post(
@@ -2116,7 +2042,7 @@ def test_rss_feed_history_disabled(self):
                     "payed_for": [1, 2],
                     "amount": "10",
                     "original_currency": "EUR",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
             )
 
@@ -2195,7 +2121,7 @@ def test_rss_if_modified_since_header(self):
                     "payed_for": [1],
                     "amount": "12",
                     "original_currency": "XXX",
-                    "bill_type": "Expense"
+                    "bill_type": "Expense",
                 },
                 follow_redirects=True,
             )
@@ -2364,7 +2290,7 @@ def test_remember_payer_per_project(self):
                 "payer": members_ids[1],
                 "payed_for": members_ids,
                 "amount": "25",
-                "bill_type": "Expense"
+                "bill_type": "Expense",
             },
         )
 
@@ -2382,7 +2308,7 @@ def test_remember_payer_per_project(self):
                 "payer": members_ids_tartif[2],
                 "payed_for": members_ids_tartif,
                 "amount": "24",
-                "bill_type": "Expense"
+                "bill_type": "Expense",
             },
         )
 
@@ -2417,7 +2343,7 @@ def test_remember_payed_for(self):
                 "payer": members_ids[1],
                 "payed_for": members_ids[1:],
                 "amount": "25",
-                "bill_type": "Expense"
+                "bill_type": "Expense",
             },
         )
 
diff --git a/tox.ini b/tox.ini
index fe2c9ad99..8a0421faa 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 isolated_build = true
-envlist = py312,py311,py310,py39,py38,py37,lint_docs
+envlist = py312,py311,py310,py39,py38,py37,lint,docs
 skip_missing_interpreters = True
 
 [testenv]
@@ -16,15 +16,21 @@ deps =
 # To be sure we are importing ihatemoney pkg from pip-installed version
 changedir = /tmp
 
-[testenv:lint_docs]
+[testenv:lint]
 commands =
     black --check --target-version=py37 .
     isort --check --profile black .
     flake8 ihatemoney
     vermin --no-tips --violations -t=3.7- .
+deps =
+    -e.[dev]
+changedir = {toxinidir}
+
+[testenv:docs]
+commands =
     sphinx-build -a -n -b html -d docs/_build/doctrees docs docs/_build/html
 deps =
-    -e.[dev,doc]
+    -e.[doc]
 changedir = {toxinidir}
 
 [flake8]