diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d690066..e3c56cf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,49 +17,45 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macOS-latest, windows-latest]
+        os: [ubuntu-latest]
         cabal: ["latest"]
         ghc:
-          # - "8.6.5"
-          - "8.8.3"
-          - "8.10.4"
-          - "9.0.1"
-        exclude:
-          - os: macOS-latest
-            ghc: 9.0.1
+          - "8.10"
+          - "9.6"
+          - "9.10"
+
+        include:
           - os: macOS-latest
-            ghc: 8.8.3
-          #- os: macOS-latest
-          #  ghc: 8.6.5
-          - os: windows-latest
-            ghc: 9.0.1
+            ghc: 9.6
           - os: windows-latest
-            ghc: 8.8.3
+            ghc: 9.6
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       if: github.event.action == 'opened' || github.event.action == 'synchronize' || github.event.ref == 'refs/heads/main'
 
-    - uses: haskell/actions/setup@v1
+    - uses: haskell-actions/setup@v2
       id: setup-haskell-cabal
       name: Setup Haskell
       with:
         ghc-version: ${{ matrix.ghc }}
         cabal-version: ${{ matrix.cabal }}
+	cabal-update: true
 
     - name: Configure
       run: |
-        cabal configure --enable-tests --enable-benchmarks --test-show-details=direct
+        cabal configure --enable-tests --enable-benchmarks --test-show-details=direct  # although we have no tests
 
     - name: Freeze
       run: |
         cabal freeze
 
-    - uses: actions/cache@v2.1.3
-      name: Cache ~/.cabal/store
-      with:
-        path: ${{ steps.setup-haskell-cabal.outputs.cabal-store }}
-        key: ${{ runner.os }}-${{ matrix.ghc }}-${{ hashFiles('cabal.project.freeze') }}
+    # drop the cache for now
+    #- uses: actions/cache@v2.1.3
+    #  name: Cache ~/.cabal/store
+    #  with:
+    #    path: ${{ steps.setup-haskell-cabal.outputs.cabal-store }}
+    #    key: ${{ runner.os }}-${{ matrix.ghc }}-${{ hashFiles('cabal.project.freeze') }}
 
     - name: Install dependencies
       run: |
@@ -81,17 +77,18 @@ jobs:
     - uses: actions/checkout@v2
       if: github.event.action == 'opened' || github.event.action == 'synchronize' || github.event.ref == 'refs/heads/main'
 
-    - uses: haskell/actions/setup@v1
+    - uses: haskell-actions/setup@v2
       name: Setup Haskell Stack
       with:
         ghc-version: ${{ matrix.ghc }}
         stack-version: ${{ matrix.stack }}
 
-    - uses: actions/cache@v2.1.3
-      name: Cache ~/.stack
-      with:
-        path: ~/.stack
-        key: ${{ runner.os }}-${{ matrix.ghc }}-stack
+    # drop the cache for now
+    #- uses: actions/cache@v2.1.3
+    #  name: Cache ~/.stack
+    #  with:
+    #    path: ~/.stack
+    #    key: ${{ runner.os }}-${{ matrix.ghc }}-stack
 
     - name: Install dependencies
       run: |
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..882757c
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,48 @@
+{
+  # inspired by: https://serokell.io/blog/practical-nix-flakes#packaging-existing-applications
+  description = "view Vega/Vega-Lite visualizations in a web browser";
+  
+  inputs = {
+    nixpkgs.url = "nixpkgs";
+  };
+  
+  outputs = { self, nixpkgs }:
+    let
+      supportedSystems = [ "x86_64-linux" "x86_64-darwin" ];
+      # supportedSystems = [ "x86_64-linux" ];
+      forAllSystems = f: nixpkgs.lib.genAttrs supportedSystems (system: f system);
+      nixpkgsFor = forAllSystems (system: import nixpkgs {
+        inherit system;
+        overlays = [ self.overlay ];
+      });
+    in
+    {
+      overlay = (final: prev: {
+        vega-view = final.haskellPackages.callCabal2nix "vega-view" ./. {};
+      });
+      packages = forAllSystems (system: {
+         vega-view = nixpkgsFor.${system}.vega-view;
+      });
+      defaultPackage = forAllSystems (system: self.packages.${system}.vega-view);
+      checks = self.packages;
+      devShell = forAllSystems (system: let haskellPackages = nixpkgsFor.${system}.haskellPackages;
+        in haskellPackages.shellFor {
+          packages = p: [self.packages.${system}.vega-view];
+          withHoogle = true;
+          buildInputs = with haskellPackages; [
+            haskell-language-server
+            hlint
+            cabal-install
+          ];
+        # Change the prompt to show that you are in a devShell
+        shellHook = ''
+  echo -e "*** \e[1;32mWelcome to vega-view development\e[0m ***"
+  ghc --version
+  cabal --version
+  hlint --version
+  echo -e ""
+  export PS1='vega-view:\A \e[1;34m\w\e[0m '
+	'';
+        });
+  };
+}
diff --git a/nix/sources.json b/nix/sources.json
index 454593c..fc78f15 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -5,22 +5,22 @@
         "homepage": "https://github.com/nmattia/niv",
         "owner": "nmattia",
         "repo": "niv",
-        "rev": "e0ca65c81a2d7a4d82a189f1e23a48d59ad42070",
-        "sha256": "1pq9nh1d8nn3xvbdny8fafzw87mj7gsmp6pxkdl65w2g18rmcmzx",
+        "rev": "f7c538837892dd2eb83567c9f380a11efb59b53f",
+        "sha256": "0xl33k24vfc29cg9lnp95kvcq69qbq5fzb7jk9ig4lgrhaarh651",
         "type": "tarball",
-        "url": "https://github.com/nmattia/niv/archive/e0ca65c81a2d7a4d82a189f1e23a48d59ad42070.tar.gz",
+        "url": "https://github.com/nmattia/niv/archive/f7c538837892dd2eb83567c9f380a11efb59b53f.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixpkgs": {
-        "branch": "release-21.05",
+        "branch": "release-24.05",
         "description": "Nix Packages collection",
         "homepage": "",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "0e03bcd64170e347a387211cb018f1ff9ea3d00d",
-        "sha256": "0x5bs9dh6431wybxs0558pdxlzv2bqs6n9i03g2a4893rb1jfmww",
+        "rev": "bbbedb870e36978f473c97dce801261014abf498",
+        "sha256": "0azx048alk7z7lqav67ha6rhk35vs8zhpd3w85050mxia18qphcf",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/0e03bcd64170e347a387211cb018f1ff9ea3d00d.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs/archive/bbbedb870e36978f473c97dce801261014abf498.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }
diff --git a/nix/sources.nix b/nix/sources.nix
index 1938409..fe3dadf 100644
--- a/nix/sources.nix
+++ b/nix/sources.nix
@@ -10,29 +10,50 @@ let
     let
       name' = sanitizeName name + "-src";
     in
-      if spec.builtin or true then
-        builtins_fetchurl { inherit (spec) url sha256; name = name'; }
-      else
-        pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
+    if spec.builtin or true then
+      builtins_fetchurl { inherit (spec) url sha256; name = name'; }
+    else
+      pkgs.fetchurl { inherit (spec) url sha256; name = name'; };
 
   fetch_tarball = pkgs: name: spec:
     let
       name' = sanitizeName name + "-src";
     in
-      if spec.builtin or true then
-        builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
-      else
-        pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
+    if spec.builtin or true then
+      builtins_fetchTarball { name = name'; inherit (spec) url sha256; }
+    else
+      pkgs.fetchzip { name = name'; inherit (spec) url sha256; };
 
   fetch_git = name: spec:
     let
       ref =
-        if spec ? ref then spec.ref else
+        spec.ref or (
           if spec ? branch then "refs/heads/${spec.branch}" else
-            if spec ? tag then "refs/tags/${spec.tag}" else
-              abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!";
+          if spec ? tag then "refs/tags/${spec.tag}" else
+          abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!"
+        );
+      submodules = spec.submodules or false;
+      submoduleArg =
+        let
+          nixSupportsSubmodules = builtins.compareVersions builtins.nixVersion "2.4" >= 0;
+          emptyArgWithWarning =
+            if submodules
+            then
+              builtins.trace
+                (
+                  "The niv input \"${name}\" uses submodules "
+                  + "but your nix's (${builtins.nixVersion}) builtins.fetchGit "
+                  + "does not support them"
+                )
+                { }
+            else { };
+        in
+        if nixSupportsSubmodules
+        then { inherit submodules; }
+        else emptyArgWithWarning;
     in
-      builtins.fetchGit { url = spec.repo; inherit (spec) rev; inherit ref; };
+    builtins.fetchGit
+      ({ url = spec.repo; inherit (spec) rev; inherit ref; } // submoduleArg);
 
   fetch_local = spec: spec.path;
 
@@ -66,16 +87,16 @@ let
       hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath;
       hasThisAsNixpkgsPath = <nixpkgs> == ./.;
     in
-      if builtins.hasAttr "nixpkgs" sources
-      then sourcesNixpkgs
-      else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then
-        import <nixpkgs> {}
-      else
-        abort
-          ''
-            Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
-            add a package called "nixpkgs" to your sources.json.
-          '';
+    if builtins.hasAttr "nixpkgs" sources
+    then sourcesNixpkgs
+    else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then
+      import <nixpkgs> { }
+    else
+      abort
+        ''
+          Please specify either <nixpkgs> (through -I or NIX_PATH=nixpkgs=...) or
+          add a package called "nixpkgs" to your sources.json.
+        '';
 
   # The actual fetching function.
   fetch = pkgs: name: spec:
@@ -95,13 +116,13 @@ let
   # the path directly as opposed to the fetched source.
   replace = name: drv:
     let
-      saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name;
+      saneName = stringAsChars (c: if (builtins.match "[a-zA-Z0-9]" c) == null then "_" else c) name;
       ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}";
     in
-      if ersatz == "" then drv else
-        # this turns the string into an actual Nix path (for both absolute and
-        # relative paths)
-        if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
+    if ersatz == "" then drv else
+      # this turns the string into an actual Nix path (for both absolute and
+      # relative paths)
+    if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}";
 
   # Ports of functions for older nix versions
 
@@ -112,7 +133,7 @@ let
   );
 
   # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295
-  range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1);
+  range = first: last: if first > last then [ ] else builtins.genList (n: first + n) (last - first + 1);
 
   # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257
   stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1));
@@ -123,43 +144,46 @@ let
   concatStrings = builtins.concatStringsSep "";
 
   # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331
-  optionalAttrs = cond: as: if cond then as else {};
+  optionalAttrs = cond: as: if cond then as else { };
 
   # fetchTarball version that is compatible between all the versions of Nix
   builtins_fetchTarball = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchTarball;
     in
-      if lessThan nixVersion "1.12" then
-        fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
-      else
-        fetchTarball attrs;
+    if lessThan nixVersion "1.12" then
+      fetchTarball ({ inherit url; } // (optionalAttrs (name != null) { inherit name; }))
+    else
+      fetchTarball attrs;
 
   # fetchurl version that is compatible between all the versions of Nix
   builtins_fetchurl = { url, name ? null, sha256 }@attrs:
     let
       inherit (builtins) lessThan nixVersion fetchurl;
     in
-      if lessThan nixVersion "1.12" then
-        fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; }))
-      else
-        fetchurl attrs;
+    if lessThan nixVersion "1.12" then
+      fetchurl ({ inherit url; } // (optionalAttrs (name != null) { inherit name; }))
+    else
+      fetchurl attrs;
 
   # Create the final "sources" from the config
   mkSources = config:
-    mapAttrs (
-      name: spec:
-        if builtins.hasAttr "outPath" spec
-        then abort
-          "The values in sources.json should not have an 'outPath' attribute"
-        else
-          spec // { outPath = replace name (fetch config.pkgs name spec); }
-    ) config.sources;
+    mapAttrs
+      (
+        name: spec:
+          if builtins.hasAttr "outPath" spec
+          then
+            abort
+              "The values in sources.json should not have an 'outPath' attribute"
+          else
+            spec // { outPath = replace name (fetch config.pkgs name spec); }
+      )
+      config.sources;
 
   # The "config" used by the fetchers
   mkConfig =
     { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null
-    , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile)
+    , sources ? if sourcesFile == null then { } else builtins.fromJSON (builtins.readFile sourcesFile)
     , system ? builtins.currentSystem
     , pkgs ? mkPkgs sources system
     }: rec {
@@ -171,4 +195,4 @@ let
     };
 
 in
-mkSources (mkConfig {}) // { __functor = _: settings: mkSources (mkConfig settings); }
+mkSources (mkConfig { }) // { __functor = _: settings: mkSources (mkConfig settings); }
diff --git a/release.nix b/release.nix
index 2c3b71a..0c6d009 100644
--- a/release.nix
+++ b/release.nix
@@ -1,6 +1,6 @@
 { sources ? import ./nix/sources.nix
 , pkgs ? import sources.nixpkgs {}
-, compiler ? "ghc8104"
+, compiler ? "ghc96"
 }:
 
 let
diff --git a/stack.yaml b/stack.yaml
index 4bfddf4..59b4e69 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,11 +1,11 @@
-resolver: lts-18.13
+resolver: lts-22.24
 
 packages:
 - .
 
-extra-deps:
-- aeson-2.0.1.0
-- semialign-1.2
-- time-compat-1.9.6.1
-- hashable-1.3.4.1
-- scotty-0.12
+#extra-deps:
+#- aeson-2.1.2.1
+#- semialign-1.2
+#- time-compat-1.9.6.1
+#- hashable-1.3.4.1
+#- scotty-0.12