diff --git a/.gitea/workflows/test.yml b/.gitea/workflows/test.yml
index 56ac1dd..cd2b2bf 100644
--- a/.gitea/workflows/test.yml
+++ b/.gitea/workflows/test.yml
@@ -25,6 +25,22 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: "3.10"
+      - name: Configure apt proxy
+        run: |
+          set -euo pipefail
+          PROXY_HOST="http://apt-cacher:3142"
+          if ! curl -fsS --connect-timeout 3 "${PROXY_HOST}" >/dev/null; then
+            PROXY_HOST="http://192.168.88.14:3142"
+          fi
+          echo "Using APT proxy ${PROXY_HOST}"
+          echo "http_proxy=${PROXY_HOST}" >> "$GITHUB_ENV"
+          echo "https_proxy=${PROXY_HOST}" >> "$GITHUB_ENV"
+          echo "HTTP_PROXY=${PROXY_HOST}" >> "$GITHUB_ENV"
+          echo "HTTPS_PROXY=${PROXY_HOST}" >> "$GITHUB_ENV"
+          sudo tee /etc/apt/apt.conf.d/01proxy >/dev/null <<EOF
+          Acquire::http::Proxy "${PROXY_HOST}";
+          Acquire::https::Proxy "${PROXY_HOST}";
+          EOF
       # - name: Cache pip
       #   uses: actions/cache@v4
       #   with:
diff --git a/tests/unit/test_currency_workflow.py b/tests/unit/test_currency_workflow.py
index f3e3686..79dba58 100644
--- a/tests/unit/test_currency_workflow.py
+++ b/tests/unit/test_currency_workflow.py
@@ -1,54 +1,74 @@
-from tests.unit.test_costs import client
+from uuid import uuid4
+
+import pytest
+
+from models.currency import Currency
 
 
-def test_create_capex_with_currency_code_and_list():
-    # create scenario first (reuse helper from other tests)
-    from tests.unit.test_costs import _create_scenario
+@pytest.fixture
+def seeded_currency(db_session):
+    currency = Currency(code="GBP", name="British Pound", symbol="GBP")
+    db_session.add(currency)
+    db_session.commit()
+    db_session.refresh(currency)
 
-    sid = _create_scenario()
+    try:
+        yield currency
+    finally:
+        db_session.delete(currency)
+        db_session.commit()
+
+
+def _create_scenario(api_client):
+    payload = {
+        "name": f"CurrencyScenario-{uuid4()}",
+        "description": "Currency workflow scenario",
+    }
+    resp = api_client.post("/api/scenarios/", json=payload)
+    assert resp.status_code == 200
+    return resp.json()["id"]
+
+
+def test_create_capex_with_currency_code_and_list(api_client, seeded_currency):
+    sid = _create_scenario(api_client)
 
-    # create with currency_code
     payload = {
         "scenario_id": sid,
         "amount": 500.0,
         "description": "Capex with GBP",
-        "currency_code": "GBP",
+        "currency_code": seeded_currency.code,
     }
-    resp = client.post("/api/costs/capex", json=payload)
+    resp = api_client.post("/api/costs/capex", json=payload)
     assert resp.status_code == 200
     data = resp.json()
-    assert data["currency_code"] == "GBP" or data.get(
-        "currency", {}).get("code") == "GBP"
+    assert data.get("currency_code") == seeded_currency.code or data.get(
+        "currency", {}
+    ).get("code") == seeded_currency.code
 
 
-def test_create_opex_with_currency_id():
-    from tests.unit.test_costs import _create_scenario
-    from routes.currencies import list_currencies
+def test_create_opex_with_currency_id(api_client, seeded_currency):
+    sid = _create_scenario(api_client)
 
-    sid = _create_scenario()
-
-    # fetch currencies to get an id
-    resp = client.get("/api/currencies/")
+    resp = api_client.get("/api/currencies/")
     assert resp.status_code == 200
     currencies = resp.json()
-    assert len(currencies) > 0
-    cid = currencies[0]["id"]
+    assert any(c["id"] == seeded_currency.id for c in currencies)
 
     payload = {
         "scenario_id": sid,
         "amount": 120.0,
         "description": "Opex with explicit id",
-        "currency_id": cid,
+        "currency_id": seeded_currency.id,
     }
-    resp = client.post("/api/costs/opex", json=payload)
+    resp = api_client.post("/api/costs/opex", json=payload)
     assert resp.status_code == 200
     data = resp.json()
-    assert data["currency_id"] == cid
+    assert data["currency_id"] == seeded_currency.id
 
 
-def test_list_currencies_endpoint():
-    resp = client.get("/api/currencies/")
+def test_list_currencies_endpoint(api_client, seeded_currency):
+    resp = api_client.get("/api/currencies/")
     assert resp.status_code == 200
     data = resp.json()
     assert isinstance(data, list)
-    assert all("id" in c and "code" in c for c in data)
+    assert any(c["id"] == seeded_currency.id for c in data)