diff --git a/CHANGELOG.md b/CHANGELOG.md
index 032d691c..a2ad9959 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 * Update task-collection commands, to align with [fractal-server 2.9.0](https://github.com/fractal-analytics-platform/fractal-server/blob/main/CHANGELOG.md#290) (\#738).
 * Remove (internal) obsolete `do_not_separate_logs` argument (\#738).
+* Testing:
+    * Align with fractal-server 2.9.0 removal of `DB_ENGINE` variable (\#743).
 
 # 2.4.0
 
diff --git a/poetry.lock b/poetry.lock
index c22b40e8..c13fecba 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,20 +1,5 @@
 # This file is automatically @generated by Poetry 1.8.2 and should not be changed by hand.
 
-[[package]]
-name = "aiosqlite"
-version = "0.19.0"
-description = "asyncio bridge to the standard sqlite3 module"
-optional = false
-python-versions = ">=3.7"
-files = [
-    {file = "aiosqlite-0.19.0-py3-none-any.whl", hash = "sha256:edba222e03453e094a3ce605db1b970c4b3376264e56f32e2a4959f948d66a96"},
-    {file = "aiosqlite-0.19.0.tar.gz", hash = "sha256:95ee77b91c8d2808bd08a59fbebf66270e9090c3d92ffbf260dc0db0b979577d"},
-]
-
-[package.extras]
-dev = ["aiounittest (==1.4.1)", "attribution (==1.6.2)", "black (==23.3.0)", "coverage[toml] (==7.2.3)", "flake8 (==5.0.4)", "flake8-bugbear (==23.3.12)", "flit (==3.7.1)", "mypy (==1.2.0)", "ufmt (==2.1.0)", "usort (==1.0.6)"]
-docs = ["sphinx (==6.1.3)", "sphinx-mdinclude (==0.5.3)"]
-
 [[package]]
 name = "alembic"
 version = "1.14.0"
@@ -711,7 +696,7 @@ typing = ["typing-extensions (>=4.12.2)"]
 
 [[package]]
 name = "fractal-server"
-version = "2.9.0a0"
+version = "2.9.0a1"
 description = "Server component of the Fractal analytics platform"
 optional = false
 python-versions = "^3.10"
@@ -719,7 +704,6 @@ files = []
 develop = false
 
 [package.dependencies]
-aiosqlite = "^0.19.0"
 alembic = "^1.13.1"
 bcrypt = "4.0.1"
 cloudpickle = ">=3.0.0,<3.1.0"
@@ -742,7 +726,7 @@ uvicorn-worker = "^0.2.0"
 type = "git"
 url = "https://github.com/fractal-analytics-platform/fractal-server.git"
 reference = "main"
-resolved_reference = "cf759e2eae51e70304de1b33cc36908196eb964c"
+resolved_reference = "31666a6b4d9e48e2a0790c043e51b255011c9c39"
 
 [[package]]
 name = "ghp-import"
diff --git a/tests/fixtures_testserver.py b/tests/fixtures_testserver.py
index 5dc0aa5d..b37fcdfd 100644
--- a/tests/fixtures_testserver.py
+++ b/tests/fixtures_testserver.py
@@ -53,7 +53,6 @@ def testserver(tester, tmpdir_factory, request):
     env_file = Path(".fractal_server.env")
     with env_file.open("w") as f:
         f.write(
-            "DB_ENGINE=postgres-psycopg\n"
             "POSTGRES_HOST=localhost\n"
             f"POSTGRES_DB={DB_NAME}\n"
             "POSTGRES_USER=postgres\n"