diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000000000000000000000000000000000000..3550a30f2de389e537ee40ca5e64a77dc185c79b
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/.gitignore b/.gitignore
index 9b186399aed4de38693e315989de279f06df4243..4d73ff0428c0114389e7e365854a1315316fb2ea 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,7 @@
+# nix-related
+result
+.nix-venv
+
 docs/source/user/getting_started_0.rst
 docs/source/user/custom_nonlinearities.rst
 docs/source/user/getting_started_4_CorrelatedFields.rst
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 6a0b4f63c508d92a604763e8e3bc9f62c5948bba..670e57a94c99e034d3f97a0017c994b53951c667 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -46,7 +46,7 @@ build_docker_from_cache:
 test_serial:
   stage: test
   script:
-    - pytest-3 -q --cov=nifty8 test
+    - pytest -q --cov=nifty8 test
     - >
       python3 -m coverage report --omit "*plot*" | tee coverage.txt
     - >
@@ -57,7 +57,7 @@ test_mpi:
   variables:
     OMPI_MCA_btl_vader_single_copy_mechanism: none
   script:
-    - mpiexec -n 2 --bind-to none pytest-3 -q test/test_mpi
+    - mpiexec -n 2 --bind-to none pytest -q test/test_mpi
 
 pages:
   stage: release
diff --git a/Dockerfile b/Dockerfile
index fa5d96a46927a9f516f4c9b818b33ed5f295d3de..41d6389b6ef9457b90833bf2d952aa1f0bf34338 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,17 +3,20 @@ FROM debian:stable-slim
 RUN apt-get update && apt-get install -y \
     # Needed for setup
     git python3-pip \
-    # Packages needed for NIFTy
-    python3-scipy \
     # Documentation build dependencies
     dvipng texlive-latex-base texlive-latex-extra \
+    # Dependency of mpi4py
+    libopenmpi-dev \
+    && rm -rf /var/lib/apt/lists/*
+RUN DUCC0_OPTIMIZATION=portable pip3 install \
+    # Packages needed for NIFTy
+    scipy \
+    # Optional nifty dependencies
+    matplotlib h5py astropy ducc0 jax jaxlib mpi4py \
     # Testing dependencies
-    python3-pytest-cov jupyter \
-    # Optional NIFTy dependencies
-    python3-mpi4py python3-matplotlib python3-h5py \
-  # more optional NIFTy dependencies
-  && DUCC0_OPTIMIZATION=portable pip3 install astropy ducc0 jupyter jax jaxlib sphinx pydata-sphinx-theme jupytext \
-  && rm -rf /var/lib/apt/lists/*
+    pytest pytest-cov \
+    # Documentation build dependencies
+    jupyter nbconvert jupytext sphinx pydata-sphinx-theme
 
 # Set matplotlib backend
 ENV MPLBACKEND agg
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000000000000000000000000000000000000..c025e56baf9f47810075222f2dbe8f193314a182
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,42 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1659877975,
+        "narHash": "sha256-zllb8aq3YO3h8B/U0/J1WBgAL8EX5yWf5pMj3G0NAmc=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c0e246b9b83f637f4681389ecabcb2681b4f3af0",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1663688007,
+        "narHash": "sha256-Ei7MJAYHTGl+reg0FpAhYddtZVVNLH3FOZrMSTTznaU=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "778d8ad2d838ea605b6abcb75fa0e39331f6f60c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000000000000000000000000000000000000..ceb87184e4a9ae761e677e712b5ae8b8494f7c67
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,41 @@
+{
+  description = "Numerical Information Field Theory";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+        myPyPkgs = pkgs.python3Packages;
+
+        req.minimal = with myPyPkgs; [ numpy scipy ducc0 ];
+        req.dev = with myPyPkgs; [ pytest pytest-cov matplotlib ];
+        req.mpi = [ myPyPkgs.mpi4py pkgs.openmpi pkgs.openssh ];
+        req.jax = with myPyPkgs; [ jax jaxlib ];
+        req.rest = with myPyPkgs; [ astropy ];
+
+        req.docs = with myPyPkgs; [ sphinx jupyter jupytext ];
+        # TODO add pydata-sphinx-theme
+      in {
+        packages.default = myPyPkgs.buildPythonPackage {
+          pname = "nifty8";
+          version = "8.0";  # TODO Set this automatically
+          src = ./.;
+          nativeBuildInputs = req.minimal;
+          checkInputs =  [ myPyPkgs.pytestCheckHook ] ++ req.dev ++ req.mpi;
+          pytestFlagsArray = [ "test" ];
+          pythonImportsCheck = [ "nifty8" ];
+        };
+
+        # TODO Add version with MPI, jax and both
+
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = with myPyPkgs; [ pip venvShellHook ] ++ req.minimal ++ req.dev;
+          # ( pkgs.lib.attrValues req ) ;
+          venvDir = "./.nix-nifty-venv";
+        };
+      });
+}
diff --git a/src/library/nft.py b/src/library/nft.py
index 0dd7932c2a92dd570bfc4c5bdc2672517b31a127..729a422634add322d7ea5a004ff09eb7b8f76c9d 100644
--- a/src/library/nft.py
+++ b/src/library/nft.py
@@ -90,6 +90,10 @@ class Nufft(LinearOperator):
         Requested precision, defaults to 2e-10.
     """
     def __init__(self, target, pos, eps=2e-10):
+        try:
+            from ducc0.nufft import nu2u, u2nu
+        except ImportError:
+            raise ImportError("ducc0 needs to be installed for nifty.Nufft()")
         self._capability = self.TIMES | self.ADJOINT_TIMES
         self._target = makeDomain(target)
         if not isinstance(self._target[0], RGSpace):
diff --git a/test/test_re/test_energies.py b/test/test_re/test_energies.py
index 9df3cd1b5735164518d7c7df2c913622f719a60a..45a67dc8f99b5b79ea41a2638f5f43ea0d6b6d1c 100644
--- a/test/test_re/test_energies.py
+++ b/test/test_re/test_energies.py
@@ -1,7 +1,9 @@
 #!/usr/bin/env python3
 
-import jax.numpy as jnp
 import pytest
+pytest.importorskip("jax")
+
+import jax.numpy as jnp
 from functools import partial
 from jax import random
 from jax.tree_util import tree_map
diff --git a/test/test_re/test_hmc_1d_distributions.py b/test/test_re/test_hmc_1d_distributions.py
index 1eb520c7211f11b8815a67ec55869b5807082268..d07fb98c2cd0d77e44d4a10adc2ed4dcddc91cfa 100644
--- a/test/test_re/test_hmc_1d_distributions.py
+++ b/test/test_re/test_hmc_1d_distributions.py
@@ -1,9 +1,11 @@
 import sys
 
+import pytest
+pytest.importorskip("jax")
+
 from jax import numpy as jnp
 from jax.scipy import stats
 from numpy.testing import assert_allclose
-import pytest
 import scipy
 from scipy.special import comb
 
diff --git a/test/test_re/test_hmc_hashes.py b/test/test_re/test_hmc_hashes.py
index 219951905c4d65ed738a74dfddd488ecd5169e03..8968acd7744ecf870caa63997ecaeeba53001eb3 100644
--- a/test/test_re/test_hmc_hashes.py
+++ b/test/test_re/test_hmc_hashes.py
@@ -1,5 +1,8 @@
 import sys
 
+import pytest
+pytest.importorskip("jax")
+
 from jax import numpy as jnp
 from jax.config import config as jax_config
 from numpy import ndarray
diff --git a/test/test_re/test_hmc_leapfrog.py b/test/test_re/test_hmc_leapfrog.py
index 8062d2fc97e7374910edb4ff6970c171c0d3b27d..4efa1871fc5af6b31362810e510b90e9a54b47ce 100644
--- a/test/test_re/test_hmc_leapfrog.py
+++ b/test/test_re/test_hmc_leapfrog.py
@@ -1,4 +1,6 @@
 import pytest
+pytest.importorskip("jax")
+
 import sys
 from jax import grad
 from jax import numpy as jnp
diff --git a/test/test_re/test_hmc_pytree.py b/test/test_re/test_hmc_pytree.py
index 9a6f1e3c89e3fc1f86819834970cac3506075003..eec04c6d79707178a499e78458e6395d3e9a33d5 100644
--- a/test/test_re/test_hmc_pytree.py
+++ b/test/test_re/test_hmc_pytree.py
@@ -1,3 +1,6 @@
+import pytest
+pytest.importorskip("jax")
+
 from functools import partial
 from jax import numpy as jnp
 from jax.tree_util import tree_leaves
diff --git a/test/test_re/test_lanczos.py b/test/test_re/test_lanczos.py
index abc4edbac7510c90ccb281abba882bfd259ebae0..beea2bbb5a80893d9c4dab289a181f9eedb8d343 100644
--- a/test/test_re/test_lanczos.py
+++ b/test/test_re/test_lanczos.py
@@ -2,13 +2,15 @@
 
 # SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause
 
+import pytest
+pytest.importorskip("jax")
+
 from functools import partial
 import sys
 from jax import random
 import jax.numpy as jnp
 import numpy as np
 from numpy.testing import assert_allclose
-import pytest
 from scipy.spatial import distance_matrix
 
 import nifty8.re as jft
diff --git a/test/test_re/test_ncg.py b/test/test_re/test_ncg.py
index fbd9737d189c1fa66c4ca5a65582d1c1a839ce52..f096718ca3a07e14c922eeda49d5a0a09fa1cae3 100644
--- a/test/test_re/test_ncg.py
+++ b/test/test_re/test_ncg.py
@@ -2,10 +2,12 @@
 
 import sys
 
+import pytest
+pytest.importorskip("jax")
+
 from jax import random, value_and_grad
 import jax.numpy as jnp
 from numpy.testing import assert_allclose
-import pytest
 
 import nifty8.re as jft
 
diff --git a/test/test_re/test_refine.py b/test/test_re/test_refine.py
index 8ad0075073a0a44c1109617d34116fc4f3a83f29..05f8f8be34ac7634fc07bd2797bf6e585cafad20 100644
--- a/test/test_re/test_refine.py
+++ b/test/test_re/test_refine.py
@@ -5,13 +5,14 @@
 from functools import partial
 import sys
 
-import jax
+import pytest
+pytest.importorskip("jax")
+
 from jax import random
 import jax.numpy as jnp
 from jax.tree_util import Partial
 import numpy as np
 from numpy.testing import assert_allclose
-import pytest
 from scipy.spatial import distance_matrix
 
 import nifty8.re as jft
diff --git a/test/test_re/test_refine_util.py b/test/test_re/test_refine_util.py
index 36df85c0d076b512c1c0d541bf3ae8a3e8b94bd6..59c7fcc99fd12c340d58bb12d910dd3e2830f1e6 100644
--- a/test/test_re/test_refine_util.py
+++ b/test/test_re/test_refine_util.py
@@ -4,9 +4,11 @@
 
 from functools import partial
 
+import pytest
+pytest.importorskip("jax")
+
 import jax
 import numpy as np
-import pytest
 
 from nifty8.re import refine_chart, refine_util
 
diff --git a/test/test_re/test_stats_distributions.py b/test/test_re/test_stats_distributions.py
index 7e9e021f84d5a903f6c23c59a14f8ad7edb6de41..c911f669a4f92a2971ebdeec00a231131e680f20 100644
--- a/test/test_re/test_stats_distributions.py
+++ b/test/test_re/test_stats_distributions.py
@@ -1,6 +1,8 @@
+import pytest
+pytest.importorskip("jax")
+
 import numpy as np
 from numpy.testing import assert_allclose
-import pytest
 
 import nifty8.re as jft