diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ca00495..637218f 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -4,12 +4,30 @@ on: [push, pull_request]
 
 jobs:
 
+  pre-commit:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+    - uses: actions/checkout@v1
+    - name: Set up Python 3.8
+      uses: actions/setup-python@v1
+      with:
+        python-version: 3.8
+    - name: Install python dependencies
+      run: |
+        pip install --upgrade pip
+        pip install -e .[pre-commit]
+    - name: Run pre-commit
+      run: |
+        pre-commit install
+        pre-commit run --all-files || ( git status --short ; git diff ; exit 1 )
+
   tests:
     runs-on: ubuntu-latest
     timeout-minutes: 30
     services:
       postgres:
-        image: postgres:10
+        image: postgres:12
         ports:
           - 5432:5432
       rabbitmq:
@@ -19,51 +37,24 @@ jobs:
     strategy:
       matrix:
         python-version: [3.8]
-        backend: ['django']
     steps:
     - uses: actions/checkout@v2
 
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
 
-    - name: Install system dependencies
-      run: |
-        sudo apt update
-        sudo apt install postgresql-12
-
     - name: Install python dependencies
       run: |
         pip install --upgrade pip
         pip install -e .[testing]
-        reentry scan -r aiida
 
     - name: Run test suite
       env:
-        AIIDA_TEST_BACKEND: ${{ matrix.backend }}
         # show timings of tests
         PYTEST_ADDOPTS: "--durations=0"
         COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
       run: |
         py.test --cov aiida_gaussian --cov-append .
         coveralls
-
-  pre-commit:
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
-    steps:
-    - uses: actions/checkout@v1
-    - name: Set up Python 3.8
-      uses: actions/setup-python@v1
-      with:
-        python-version: 3.8
-    - name: Install python dependencies
-      run: |
-        pip install --upgrade pip
-        pip install -e .[pre-commit]
-        reentry scan -r aiida
-    - name: Run pre-commit
-      run: |
-        pre-commit install
-        pre-commit run --all-files || ( git status --short ; git diff ; exit 1 )
diff --git a/aiida_gaussian/calculations/gaussian.py b/aiida_gaussian/calculations/gaussian.py
index 04e5875..85b228f 100644
--- a/aiida_gaussian/calculations/gaussian.py
+++ b/aiida_gaussian/calculations/gaussian.py
@@ -11,7 +11,7 @@
 
 import pymatgen.io.gaussian as mgaus
 
-StructureData = DataFactory("structure")
+StructureData = DataFactory("core.structure")
 
 
 class GaussianCalculation(CalcJob):
diff --git a/aiida_gaussian/tests/test_gaussian.py b/aiida_gaussian/tests/test_gaussian.py
index ffa1388..c25e72f 100644
--- a/aiida_gaussian/tests/test_gaussian.py
+++ b/aiida_gaussian/tests/test_gaussian.py
@@ -52,7 +52,7 @@ def test_gaussian(fixture_code):
     inputs = {
         'code': fixture_code('gaussian'),  #load_code("gaussian09@localhost"),
         'structure': structure,
-        'parameters': Dict(dict=parameters),
+        'parameters': Dict(parameters),
         'metadata': {
             'options': {
                 'resources': {
diff --git a/aiida_gaussian/workchains/base.py b/aiida_gaussian/workchains/base.py
index 8c6c567..8e0b354 100644
--- a/aiida_gaussian/workchains/base.py
+++ b/aiida_gaussian/workchains/base.py
@@ -10,7 +10,7 @@
 from aiida.plugins import CalculationFactory, DataFactory
 
 GaussianCalculation = CalculationFactory('gaussian')
-StructureData = DataFactory('structure')
+StructureData = DataFactory('core.structure')
 
 
 class GaussianBaseWorkChain(BaseRestartWorkChain):
@@ -96,7 +96,7 @@ def handle_scf_failure(self, node):
 
         # Update the params Dict
         route_params['scf'] = new_scf
-        self.ctx.inputs.parameters = Dict(dict=params)
+        self.ctx.inputs.parameters = Dict(params)
 
         return ProcessHandlerReport(True)
 
diff --git a/aiida_gaussian/workchains/cubes.py b/aiida_gaussian/workchains/cubes.py
index d083e9d..6c668f0 100644
--- a/aiida_gaussian/workchains/cubes.py
+++ b/aiida_gaussian/workchains/cubes.py
@@ -282,7 +282,7 @@ def cubegen_step(self):
         builder.parent_calc_folder = self.ctx.formchk_node.outputs.remote_folder
         builder.code = self.inputs.cubegen_code
         builder.stencil = SinglefileData(io.BytesIO(stencil))
-        builder.parameters = Dict(dict=params_dict)
+        builder.parameters = Dict(params_dict)
         builder.retrieve_cubes = self.inputs.retrieve_cubes
 
         builder.parser_params = self.inputs.cubegen_parser_params
diff --git a/examples/example_01_opt.py b/examples/example_01_opt.py
index 3d15404..7a59878 100644
--- a/examples/example_01_opt.py
+++ b/examples/example_01_opt.py
@@ -28,26 +28,24 @@ def example_dft(gaussian_code):
     memory_mb = 300
 
     # Main parameters: geometry optimization
-    parameters = Dict(
-        dict={
-            'link0_parameters': {
-                '%chk': 'aiida.chk',
-                '%mem': "%dMB" % memory_mb,
-                '%nprocshared': num_cores,
+    parameters = Dict({
+        'link0_parameters': {
+            '%chk': 'aiida.chk',
+            '%mem': "%dMB" % memory_mb,
+            '%nprocshared': num_cores,
+        },
+        'functional': 'BLYP',
+        'basis_set': '6-31g',
+        'charge': 0,
+        'multiplicity': 1,
+        'route_parameters': {
+            'scf': {
+                'cdiis': None,
             },
-            'functional': 'BLYP',
-            'basis_set': '6-31g',
-            'charge': 0,
-            'multiplicity': 1,
-            'route_parameters': {
-                'scf': {
-                    'cdiis': None,
-                },
-                'nosymm': None,
-                'opt': None,
-            },
-        }
-    )
+            'nosymm': None,
+            'opt': None,
+        },
+    })
 
     # Construct process builder
 
diff --git a/examples/example_02_output_wfx.py b/examples/example_02_output_wfx.py
index 2954042..215e611 100644
--- a/examples/example_02_output_wfx.py
+++ b/examples/example_02_output_wfx.py
@@ -30,24 +30,22 @@ def example_dft(gaussian_code):
     memory_mb = 300
 
     # parameters
-    parameters = Dict(
-        dict={
-            'link0_parameters': {
-                '%chk': 'aiida.chk',
-                '%mem': '%dMB' % memory_mb,
-                '%nprocshared': num_cores,
-            },
-            'functional': 'PBE1PBE',
-            'basis_set': '6-31g',
-            'route_parameters': {
-                'nosymm': None,
-                'Output': 'WFX'
-            },
-            'input_parameters': {
-                'output.wfx': None
-            },
-        }
-    )
+    parameters = Dict({
+        'link0_parameters': {
+            '%chk': 'aiida.chk',
+            '%mem': '%dMB' % memory_mb,
+            '%nprocshared': num_cores,
+        },
+        'functional': 'PBE1PBE',
+        'basis_set': '6-31g',
+        'route_parameters': {
+            'nosymm': None,
+            'Output': 'WFX'
+        },
+        'input_parameters': {
+            'output.wfx': None
+        },
+    })
 
     # Construct process builder
 
diff --git a/examples/example_03_base_workflow.py b/examples/example_03_base_workflow.py
index b7918e1..e1c3bc1 100644
--- a/examples/example_03_base_workflow.py
+++ b/examples/example_03_base_workflow.py
@@ -32,33 +32,31 @@ def example_dft(gaussian_code):
     memory_mb = 300
 
     # Main parameters: geometry optimization
-    parameters = Dict(
-        dict={
-            'link0_parameters': {
-                '%chk': 'aiida.chk',
-                '%mem': "%dMB" % memory_mb,
-                '%nprocshared': num_cores,
+    parameters = Dict({
+        'link0_parameters': {
+            '%chk': 'aiida.chk',
+            '%mem': "%dMB" % memory_mb,
+            '%nprocshared': num_cores,
+        },
+        'functional': 'B3LYP',
+        'basis_set': '6-31g',
+        'charge': 0,
+        'multiplicity': 1,
+        'route_parameters': {
+            'scf': {
+                'conver': 7,
+                'maxcycle': 140,
             },
-            'functional': 'B3LYP',
-            'basis_set': '6-31g',
-            'charge': 0,
-            'multiplicity': 1,
-            'route_parameters': {
-                'scf': {
-                    'conver': 7,
-                    'maxcycle': 140,
-                },
-                'sp': None,
-            },
-        }
-    )
+            'sp': None,
+        },
+    })
 
     # Construct process builder
 
     builder = GaussianBaseWorkChain.get_builder()
 
     # Handle the ASyTop error
-    builder.handler_overrides = Dict(dict={'handle_asytop_error': True})
+    builder.handler_overrides = Dict({'handle_asytop_error': True})
 
     builder.gaussian.structure = structure
     builder.gaussian.parameters = parameters
diff --git a/examples/example_cubes_workchain.py b/examples/example_cubes_workchain.py
index 74117b7..faadc79 100644
--- a/examples/example_cubes_workchain.py
+++ b/examples/example_cubes_workchain.py
@@ -37,27 +37,25 @@ def example(gaussian_code, formchk_code, cubegen_code):
     builder = GaussianCalculation.get_builder()
     builder.code = gaussian_code
     builder.structure = struct_node
-    builder.parameters = Dict(
-        dict={
-            'link0_parameters': {
-                '%chk': 'aiida.chk',
-                '%mem': "%dMB" % memory_mb,
-                '%nprocshared': str(num_cores),
+    builder.parameters = Dict({
+        'link0_parameters': {
+            '%chk': 'aiida.chk',
+            '%mem': "%dMB" % memory_mb,
+            '%nprocshared': str(num_cores),
+        },
+        'functional': 'UB3LYP',
+        'basis_set': '6-31g',
+        'charge': 0,
+        'multiplicity': 1,
+        'route_parameters': {
+            'scf': {
+                'cdiis': None,
             },
-            'functional': 'UB3LYP',
-            'basis_set': '6-31g',
-            'charge': 0,
-            'multiplicity': 1,
-            'route_parameters': {
-                'scf': {
-                    'cdiis': None,
-                },
-                'guess': 'mix',
-                'nosymm': None,
-                'sp': None,
-            },
-        }
-    )
+            'guess': 'mix',
+            'nosymm': None,
+            'sp': None,
+        },
+    })
     builder.metadata.options.resources = {
         "tot_num_mpiprocs": num_cores,
         "num_machines": 1,
diff --git a/pyproject.toml b/pyproject.toml
index af754b2..7ecfaec 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ classifiers = [
 ]
 requires-python = ">=3.7"
 dependencies = [
-    "aiida-core>=1.0.0,<2.0.0",
+    "aiida-core>=2.0.0,<3.0.0",
     "pymatgen>=2020.4,<2022.0.0",
     "cclib>=1.6.1,<=1.7",
     "ase",