add modifiable homeManager

we won't depend on it (i force that)
but it's good to allow following

CHANGELOG.md

@@ -0,0 +1,25 @@
+# Changelog
+
+## v0.2.0-alpha
+Initial "stable" release. Cerulean is currently usable and supports:
+1. local & remote deployment configuration
+2. nixos/homemanager module-level support for any number of nixpkg branches
+3. use of the [nix-systems standard](https://github.com/nix-systems/nix-systems), the introduction of the `snow/flake` standard, and the introduction of the `nixpkgs.nix` standard module.
+4. hierarchical groups for NixOS hosts via `snow.nix`
+
+This is still a alpha-build of Cerulean. Everything will break in the future as I change the internals a bunch. I'll aim to write documentation in future cause currently there's no guide.
+
+## v0.2.1-alpha
+Minor patches
+- cerulean no longer has a `inputs.nixpkgs-unstable` (the `nixpkgs.nix` is the new alternative)
+- `home-manager.nixosModules.default` and `microvm.nixosModules.microvm` are added as default modules
+- fixed `groups.all` not being added to nodes with `groups = []`
+
+## v0.2.2-alpha
+Minor patches
+- fixed `nexus.groups.all` not added to empty `nexus.nodes.*.groups` declarations
+- fixed bad propagation of inputs
+- forced system architecture to be specified per node
+- cerulean no longer depends on `nixpkgs`,  `base` package set should be set instead
+- rename `extraModules` -> `modules`
+- rename `specialArgs` -> `args`

README.md

@@ -1,19 +1,51 @@
+![enbyware](https://pride-badges.pony.workers.dev/static/v1?label=enbyware&labelColor=%23555&stripeWidth=8&stripeColors=FCF434%2CFFFFFF%2C9C59D1%2C2C2C2C)
+![repo size](https://img.shields.io/github/repo-size/cry128/cerulean)
+
 >[!WARNING]
 > ✨ **Under Construction** ✨
-> Cerulean has lived rent free in my head for the last 12 months.
-> I'm developing this project for personal use and especially
-> for use at my workplace. **Be not afraid!** It's only a matter
-> of time until Cerulean is ready for use!
+>
+> Cerulean is in an **experimental alpha release stage**.<br/>
+> **Be not afraid!** It's only a matter of time until Cerulean is ready for use!
+>
+> If you're curious about or want to use Cerulean then<br/>
+> *please please please* contact me on Bluesky [@dobutterfliescry.net](https://bsky.app/profile/dobutterfliescry.net).<br/>
+> (i would actually *melt* and fall in love with you...)
+
+# 🌌 🚀 Cerulean Nexus
+The culmination of 2 years designing better Nix flakes. Cerulean removes the boilerplate of managing
+NixOS infrastructure by declaring each machine as a **node** and their relationships as *"Nexus Networks"*,
+virtual networks of servers that Cerulean can manage. Each Nexus is **very powerful**. Allowing for simple
+distributed computing, automatic construction of VPNs, DNS for local hostnames, and that's just scratching the surface...
+
+- Is your node a VPS? Set `deploy.ssh.host = "example.com"` and Cerulean will configure custom build users,
+  ssh deployment via custom PAM modules, etc etc
+- Is your node a VM? Set `vms = [ nodes.VM_NODE ]` on your host node, and Cerulean will configure
+  all the bridging, NAT, and other networking you so desire!
+
+## 🩷💜 Motivation
+Nix is intended as a non-restrictive & unopinionated system, which is amazing, but it also means
+every user develops their own standards to simplify their config. Cerulean however is very much
+opinionated and contains all the standards I personally believe should be sane defaults for every NixOS machine.
+
+> Flakes are not designed for NixOS, they're designed for Nix, and that's an important distinction.
+
+Flakes and NixOS don't offer anything to simplify managing interconnected nodes of machines.
+But this ends with *extremely messy configs* with **a lot of footguns**. You shouldn't have to spend
+days reading about networking and learning to work with other peoples' modules.
+
+Finally, the Nix module system assumes you only use one channel of `github:NixOS/nixpkgs` but this
+just isn't realistic. Most people have both `inputs.nixpkgs` and `inputs.nixpkgs-unstable` defined.
+So cerulean declares the `nixpkgs.channels.*` option so you don't have to import your channels
+manually!
 
 ## 💙 Same Colour, More Control
-Cerulean is what you wish Azure could be. An expansive collection of microservices, pre-configured systems,
+>[!NOTE]
+> This section is *mostly* for the business minded people.
+
+Cerulean is what you wish Azure could be. Providing an expansive collection of microservices, pre-configured systems,
 and entirely self-hosted! Cerulean is built using NixOS as a foundation so you know it's never going to break randomly.
 NixOS backing makes Cerulean **extremely scalable**! Just rent a new VPS and Cerulean will build an ISO of your configuration.
 
 No stress, no hassle!
 Say goodbye to Azure! And say goodbye to Kubernetes! You're taking life into your own hands 💙
 
-### 🌌 🚀 Nexus
-Cerulean allows you to declare *"Nexus Networks"*, virtual networks of servers that Cerulean can manage.
-Each Nexus is **very powerful**. Allowing for simple distributed computing, automatic construction of a wireguard
-VPN, distributed DNS for local hostnames, and that's just scratching the surface...

TODO.md

@@ -1,14 +1,64 @@
+- [ ] base should automatically be set as the default (dont do anything with the default)
+- [ ] try to remove common foot guns, ie abort if the user provides the home-manager or microvm nixosModules
+      since cerulean ALREADY provides these
+
+- [ ] deploy port should default to the first port given to `services.openssh`
+
 - [ ] use the Nix module system instead of projectOnto for `cerulean.mkNexus`
+- [ ] create an alternative to nixos-install called cerulean-install that
+      allows people to easily bootstrap new machines (and host it on dobutterfliescry.net)
+
 - [ ] find an alternative to `nix.settings.trusted-users` probably
+- [ ] add the ceru-build user, 
 - [ ] add support for github:microvm-nix/microvm.nix
 - [ ] add support for sops-nix
 
-- [ ] create an alternative to nixos-install called cerulean-install that
-      allows people to easily bootstrap new machines
+- [ ] it would be cool to enable/disable groups and hosts
+- [ ] find a standard for how nixpkgs.nix can have a different base per group
+
+- [ ] go through all flake inputs (recursively) and ENSURE we remove all duplicates by using follows!!
+
+- [X] rename nixos-modules/ to nixos/
+- [X] ensure all machines are in groups.all by default
+
+- [X] fix nixpkgs.nix not working (default not respected)
+- [X] remove dependence on nixpkgs
+
+- [ ] allow multiple privesc methods, the standard is pam_ssh_agent_auth
+
+## Low Priority
+- [X] rename extraModules to modules?
+- [X] rename specialArgs to args?
+
+- [ ] make an extension to the nix module system (different to mix)
+      that allows transformations (ie a stop post config, ie outputs, which
+      it then returns instead of config)
 
 
-- [ ] rename nixos-modules/ to nixos/
+- [ ] what if we automated the process of replacing windows with Nix??
+      then push this to nixos-anywhere or nix-infect lmaooo
 
+- [ ] patch microvm so that acpi=off https://github.com/microvm-nix/microvm.nix/commit/b59a26962bb324cc0a134756a323f3e164409b72
+      cause otherwise 2GB causes a failure
 
-- [ ] add the ceru-build user
-- [ ] ensure all machines are in groups.all by default
+- [ ] rewrite the ceru cli in rust
+- [ ] make `ceru` do local and remote deployments
+
+- [ ] support `legacyImports` 
+
+```nix
+# REF: foxora
+vms = {
+  home-assistant = {
+    autostart = true;
+    # matches in vms/*
+    image = "home-assistant";
+    options = {
+      mem = 2048;
+    };
+  };
+  equinox = {
+    image = "home-assistant";
+  };
+};
+```

cerulean/default.nix

@@ -21,11 +21,11 @@ mix.newMixture args (mixture: {
     ./nexus
   ];
 
-  version = "0.2.1";
+  version = "0.2.2";
 
   nixosModules = rec {
     default = cerulean;
-    cerulean = ./nixos-module;
+    cerulean = ./nixos;
   };
 
   overlays = [

cerulean/nexus/nexus.nix

@@ -15,12 +15,12 @@
   self,
   this,
   nt,
-  lib,
   inputs,
   ...
 }: let
   inherit
     (builtins)
+    all
     attrNames
     concatLists
     concatStringsSep
@@ -50,15 +50,11 @@
       (nt.naive.terminal)
       Terminal
       ;
-
-    missing = msg: path:
-      Terminal (abort ''
-        Each Cerulean Nexus node is required to specify ${msg}!
-        Ensure `nexus.${path}` exists under your call to `cerulean.mkNexus`.
-      '');
   in {
-    extraModules = [];
-    specialArgs = Terminal {};
+    base = null;
+    modules = [];
+    args = Terminal {};
+    homeManager = null;
 
     groups = Terminal {};
     nodes = Terminal {};
@@ -96,15 +92,15 @@
     assert isAttrs nexus
     || abort ''
       Cerulean Nexus config must be provided as an attribute set, got "${typeOf nexus}" instead!
-      Ensure all the `nexus` declaration is an attribute set under your call to `cerulean.mkNexus`.
+      Ensure the `nexus` declaration is an attribute set under your call to `cerulean.mkNexus`.
     ''; let
-      base = nt.projectOnto templateNexus nexus;
+      decl = nt.projectOnto templateNexus nexus;
     in
       # XXX: TODO: create a different version of nt.projectOnto that can actually
       # XXX: TODO: handle applying a transformation to the result of each datapoint
-      base
+      decl
       // {
-        groups = parseGroupDecl base.groups;
+        groups = parseGroupDecl decl.groups;
       };
 
   parseDecl = outputsBuilder: let
@@ -133,7 +129,14 @@
       Cerulean Nexus node "${nodeName}" does not declare group membership as a list, got "${typeOf node.groups}" instead!
       Ensure `nexus.nodes.${nodeName}.groups` is a list under your call to `cerulean.mkNexus`.
     '';
-      node.groups
+    # ensure root group is always added
+      (node.groups
+        ++ [
+          {
+            _parent = null;
+            _name = ROOT_GROUP_NAME;
+          }
+        ])
       # ensure all members are actually groups
       |> map (group: let
         got =
@@ -181,38 +184,63 @@ in {
     customOutputs = removeAttrs decl ["nexus"];
 
     outputs = rec {
-      nixosConfigurations = mapNodes nexus.nodes (
-        nodeName: node: let
-          nixosDecl = lib.nixosSystem {
-            system = node.system;
-            specialArgs = let
-              specialArgs =
-                nexus.specialArgs
-                // node.specialArgs
-                // {
-                  inherit root specialArgs;
-                  inherit (node) system;
-                  _deploy-rs = inputs.deploy-rs;
-                };
-            in
-              specialArgs;
-            modules =
-              [
-                self.nixosModules.default
-                (findImport (root + "/hosts/${nodeName}"))
+      nixosConfigurations = mapNodes nexus (
+        {
+          base,
+          lib,
+          nodeName,
+          node,
+          ...
+        }: let
+          nixosDecl = let
+            homeManager =
+              if node.homeManager != null
+              then node.homeManager
+              else nexus.homeManager;
 
-                inputs.home-manager.nixosModules.default
-                inputs.microvm.nixosModules.microvm
-              ]
-              ++ (getGroupModules root nodeName node)
-              ++ node.extraModules
-              ++ nexus.extraModules;
-          };
+            userArgs = nexus.args // node.args;
+            ceruleanArgs = {
+              inherit root base;
+              inherit (node) system;
+              _cerulean = {
+                inherit inputs userArgs ceruleanArgs homeManager;
+                specialArgs = userArgs // ceruleanArgs;
+              };
+            };
+            specialArgs = assert (userArgs
+              |> attrNames
+              |> all (argName:
+                ! ceruleanArgs ? argName
+                || abort ''
+                  `specialArgs` are like super important to Cerulean my love... </3
+                  But `args.${argName}` is a reserved argument name :(
+                ''));
+              ceruleanArgs._cerulean.specialArgs;
+          in
+            lib.nixosSystem {
+              inherit (node) system;
+              inherit specialArgs;
+              modules =
+                [
+                  self.nixosModules.default
+                  (findImport (root + "/hosts/${nodeName}"))
+
+                  # inputs.microvm.nixosModules.microvm
+                ]
+                ++ (homeManager.nixosModules.default or [])
+                ++ (getGroupModules root nodeName node)
+                ++ node.modules
+                ++ nexus.modules;
+            };
         in
           nixosDecl
       );
 
-      deploy.nodes = mapNodes nexus.nodes (nodeName: node: let
+      deploy.nodes = mapNodes nexus ({
+        nodeName,
+        node,
+        ...
+      }: let
         inherit
           (node.deploy)
           activationTimeout

cerulean/nexus/nodes.nix

@@ -25,11 +25,22 @@ in rec {
       (nt.naive.terminal)
       Terminal
       ;
+
+    missing = msg: path:
+      Terminal (abort ''
+        Each Cerulean Nexus node is required to specify ${msg}!
+        Ensure `nexus.${path}` exists under your call to `cerulean.mkNexus`.
+      '');
   in {
-    system = "x86_64-linux"; # sane default (i hope...)
+    enabled = true;
+    system = missing "its system architecture" "system";
     groups = [];
-    extraModules = [];
-    specialArgs = Terminal {};
+    modules = [];
+    args = Terminal {};
+
+    homeManager = null;
+
+    base = null;
 
     deploy = {
       user = "root";
@@ -66,7 +77,25 @@ in rec {
     in
       nt.projectOnto templateAttrs nodeAttrs;
 
-  mapNodes = nodes: f:
-    nodes
-    |> mapAttrs (nodeName: nodeAttrs: f nodeName (parseNode nodeName nodeAttrs));
+  mapNodes = nexus: f:
+    nexus.nodes
+    |> mapAttrs (nodeName: nodeAttrs: let
+      node = parseNode nodeName nodeAttrs;
+
+      # use per-node base or default to nexus base
+      base =
+        if node.base != null
+        then node.base
+        else if nexus.base != null
+        then nexus.base
+        else
+          abort ''
+            Cerulean cannot construct nexus node "${nodeName}" without a base package source.
+            Ensure `nexus.nodes.*.base` or `nexus.base` is a flake reference to the github:NixOS/nixpkgs repository.
+          '';
+    in
+      f {
+        inherit nodeName node base;
+        inherit (base) lib;
+      });
 }

cerulean/nexus/snow.nix

@@ -0,0 +1,108 @@
+# Copyright 2026 Emile Clark-Boman
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+{
+  inputs,
+  lib,
+  ...
+}: {
+  # nexus
+  options = let
+    inherit
+      (lib)
+      mkOption
+      types
+      ;
+  in {
+    modules = mkOption {
+      type = types.listOf types.path;
+    };
+    args = mkOption {
+      type = types.attrs;
+    };
+
+    groups = mkOption {
+      type = types.attrs;
+    };
+
+    nodes = mkOption {
+      type = types.attrsOf (types.submoduleWith ({...}: {
+        options = {
+          enabled = mkOption {
+            type = types.bool;
+            default = true;
+          };
+          system = mkOption {
+            type = types.enum inputs.systems;
+          };
+          groups = mkOption {
+            type = types.list;
+          };
+          modules = mkOption {
+            type = types.list;
+          };
+          args = mkOption {
+            type = types.attrs;
+          };
+
+          deploy = {
+            user = mkOption {
+              type = types.str;
+            };
+            sudoCmd = mkOption {
+              type = types.str;
+            };
+            interactiveSudo = mkOption {
+              type = types.bool;
+            };
+
+            remoteBuild = mkOption {
+              type = types.bool;
+            };
+            autoRollback = mkOption {
+              type = types.bool;
+            };
+            magicRollback = mkOption {
+              type = types.bool;
+            };
+
+            activationTimeout = mkOption {
+              type = types.int;
+            };
+            confirmTimeout = mkOption {
+              type = types.int;
+            };
+
+            ssh = {
+              host = mkOption {
+                type = types.str;
+              };
+              user = mkOption {
+                type = types.str;
+              };
+              port = mkOption {
+                type = types.int;
+              };
+              opts = mkOption {
+                type = types.listOf types.str;
+              };
+            };
+          };
+        };
+      }));
+    };
+  };
+
+  config = {
+  };
+}

cerulean/nixos-module/nixpkgs.nix

@@ -1,101 +0,0 @@
-# Copyright 2026 Emile Clark-Boman
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-{
-  lib,
-  system,
-  config,
-  contextName,
-  ...
-}: let
-  inherit
-    (builtins)
-    mapAttrs
-    ;
-
-  cfg = config.nixpkgs.channels;
-in {
-  options.nixpkgs.channels = lib.mkOption {
-    type = lib.types.attrsOf (lib.types.attrs);
-    default = {};
-    description = "Declare package repositories per module context (nixos, home-manager, etc)";
-    example = {
-      "homes" = {
-        "pkgs" = {
-          source = "inputs.nixpkgs";
-          system = "x86-64-linux";
-          config = {
-            allowUnfree = true;
-            allowBroken = false;
-          };
-        };
-        "upkgs" = {
-          source = "inputs.nixpkgs-unstable";
-          system = "x86-64-linux";
-          config = {
-            allowUnfree = true;
-            allowBroken = false;
-          };
-        };
-      };
-    };
-  };
-
-  config = let
-    # TODO: use lib.types.submodule to restrict what options
-    # TODO: can be given to `nixpkgs.channels.${moduleName}.${name}`
-    decl =
-      cfg.${contextName} or cfg.default;
-
-    repos =
-      decl
-      |> mapAttrs (
-        name: args:
-          lib.mkForce (
-            assert args ? source
-            || abort ''
-              ${toString ./.}
-              `nixpkgs.channels.${contextName}.${name}` missing required attribute "source"
-            '';
-              ((removeAttrs args ["source"])
-                // {inherit system;})
-              |> import args.source
-          )
-      );
-  in {
-    # NOTE: _module.args is a special option that allows us to
-    # NOTE: set extend specialArgs from inside the modules.
-    _module.args = repos;
-
-    nixpkgs = let
-      defaultPkgs =
-        decl.default or (throw ''
-          Your `nixpkgs.nix` file does not declare a default package source.
-          Ensure you set `nixpkgs.channels.*.default = ...;`
-        '');
-    in
-      if contextName == "hosts"
-      then {
-        flake.source = lib.mkOverride 200 defaultPkgs.source;
-        config = lib.mkOverride 200 defaultPkgs.config;
-      }
-      else if contextName == "homes"
-      then {
-        # XXX: XXX: XXX: OH OH OH OMG, its because aurora never defines pkgs
-        config = lib.mkOverride 200 (defaultPkgs.config or {});
-        # XXX: WARNING: TODO: modify options so overlays must always be given as the correct type
-        overlays = lib.mkOverride 200 (defaultPkgs.overlays or []);
-      }
-      else {};
-  };
-}

cerulean/nixos/default.nix

@@ -0,0 +1,36 @@
+# Copyright 2026 Emile Clark-Boman
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+{
+  root,
+  system,
+  _cerulean,
+  ...
+} @ args: {
+  imports =
+    [
+      # user configuration
+      (import (root + "/nixpkgs.nix"))
+      # options declarations
+      (import ./nixpkgs.nix (args // {contextName = "hosts";}))
+    ]
+    ++ (
+      if _cerulean.homeManager != null
+      then [./home-manager.nix]
+      else []
+    );
+
+  environment.systemPackages = with _cerulean.inputs; [
+    deploy-rs.packages.${system}.default
+  ];
+}

cerulean/nixos/home-manager.nix

@@ -13,10 +13,9 @@
 # limitations under the License.
 {
   root,
-  system,
   config,
   lib,
-  specialArgs,
+  _cerulean,
   ...
 } @ args: let
   inherit
@@ -26,25 +25,21 @@
     pathExists
     ;
 in {
-  config = {
-    home-manager = {
-      users =
-        config.users.users
-        |> attrNames
-        |> filter (x: pathExists (root + "/homes/${x}"))
-        |> (x: lib.genAttrs x (y: import (root + "/homes/${y}")));
+  home-manager = {
+    users =
+      config.users.users
+      |> attrNames
+      |> filter (x: pathExists (root + "/homes/${x}"))
+      |> (x:
+        lib.genAttrs x (y:
+          import (root + "/homes/${y}")));
 
-      extraSpecialArgs = {inherit root system;} // (specialArgs.inputs or {});
-      sharedModules = [
-        # user configuration
-        (import (root + "/nixpkgs.nix"))
-        # options declarations
-        (import ./nixpkgs.nix (args // {contextName = "homes";}))
-      ];
-
-      # disable home-manager trying anything fancy
-      # we control the pkgs now!!
-      # useGlobalPkgs = true;
-    };
+    extraSpecialArgs = _cerulean.specialArgs;
+    sharedModules = [
+      # user configuration
+      (import (root + "/nixpkgs.nix"))
+      # options declarations
+      (import ./nixpkgs.nix (args // {contextName = "homes";}))
+    ];
   };
 }

cerulean/nixos/microvm-child.nix

@@ -11,22 +11,3 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-{
-  root,
-  system,
-  _deploy-rs,
-  ...
-} @ args: {
-  imports = [
-    # user configuration
-    (import (root + "/nixpkgs.nix"))
-    # options declarations
-    (import ./nixpkgs.nix (args // {contextName = "hosts";}))
-
-    ./home-manager.nix
-  ];
-
-  environment.systemPackages = [
-    _deploy-rs.packages.${system}.default
-  ];
-}

cerulean/nixos/microvm-parent.nix

@@ -0,0 +1,13 @@
+# Copyright 2026 Emile Clark-Boman
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

cerulean/nixos/nixpkgs.nix

@@ -0,0 +1,94 @@
+# Copyright 2026 Emile Clark-Boman
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+{
+  base,
+  lib,
+  system,
+  config,
+  contextName,
+  ...
+}: let
+  inherit
+    (builtins)
+    mapAttrs
+    ;
+
+  cfg = config.nixpkgs.channels;
+in {
+  options.nixpkgs.channels = lib.mkOption {
+    type = lib.types.attrs;
+    default = {};
+    description = "Declare package repositories";
+    example = {
+      "pkgs" = {
+        source = "inputs.nixpkgs";
+        system = "x86-64-linux";
+        config = {
+          allowUnfree = true;
+          allowBroken = false;
+        };
+      };
+      "upkgs" = {
+        source = "inputs.nixpkgs-unstable";
+        system = "x86-64-linux";
+        config = {
+          allowUnfree = false;
+          allowBroken = true;
+        };
+      };
+    };
+  };
+
+  config = let
+    repos =
+      cfg
+      |> (xs: removeAttrs xs ["default"])
+      |> mapAttrs (
+        name: args:
+          lib.mkForce (
+            assert args ? source
+            || abort ''
+              `nixpkgs.channels.${name}` missing required attribute "source"
+            '';
+              import args.source ({inherit system;} // (removeAttrs args ["source"]))
+          )
+      );
+
+    # XXX: TODO: would it work to use `base` instead of having default?
+    defaultPkgs =
+      cfg.default or (throw ''
+        Your `nixpkgs.nix` file does not declare a default package source.
+        Ensure you set `nixpkgs.channels.*.default = ...;`
+      '');
+  in {
+    # NOTE: _module.args is a special option that allows us to
+    # NOTE: set extend specialArgs from inside the modules.
+    # WARNING: pkgs is a reserved specialArg
+    _module.args = removeAttrs repos ["pkgs"];
+
+    nixpkgs =
+      if contextName == "hosts"
+      then {
+        flake.source = lib.mkOverride 200 base; # DEBUG: temp while getting base to work
+        overlays = lib.mkOverride 200 (defaultPkgs.overlays or {});
+        config = lib.mkOverride 200 (defaultPkgs.config or {});
+      }
+      else if contextName == "homes"
+      then {
+        config = lib.mkOverride 200 (defaultPkgs.config or {});
+        overlays = lib.mkOverride 200 (defaultPkgs.overlays or []);
+      }
+      else {};
+  };
+}

flake.lock

@@ -3,7 +3,9 @@
     "deploy-rs": {
       "inputs": {
         "flake-compat": "flake-compat",
-        "nixpkgs": "nixpkgs",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
         "utils": "utils"
       },
       "locked": {
@@ -58,6 +60,27 @@
         "type": "github"
       }
     },
+    "microvm": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "spectrum": "spectrum"
+      },
+      "locked": {
+        "lastModified": 1771365290,
+        "narHash": "sha256-1XJOslVyF7yzf6yd/yl1VjGLywsbtwmQh3X1LuJcLI4=",
+        "owner": "microvm-nix",
+        "repo": "microvm.nix",
+        "rev": "789c90b164b55b4379e7a94af8b9c01489024c18",
+        "type": "github"
+      },
+      "original": {
+        "owner": "microvm-nix",
+        "repo": "microvm.nix",
+        "type": "github"
+      }
+    },
     "nix-github-actions": {
       "inputs": {
         "nixpkgs": [
@@ -105,38 +128,6 @@
       }
     },
     "nixpkgs": {
-      "locked": {
-        "lastModified": 1743014863,
-        "narHash": "sha256-jAIUqsiN2r3hCuHji80U7NNEafpIMBXiwKlSrjWMlpg=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "bd3bac8bfb542dbde7ffffb6987a1a1f9d41699f",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixpkgs-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs-unstable": {
-      "locked": {
-        "lastModified": 1768305791,
-        "narHash": "sha256-AIdl6WAn9aymeaH/NvBj0H9qM+XuAuYbGMZaP0zcXAQ=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "1412caf7bf9e660f2f962917c14b1ea1c3bc695e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixos-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs_2": {
       "locked": {
         "lastModified": 1768323494,
         "narHash": "sha256-yBXJLE6WCtrGo7LKiB6NOt6nisBEEkguC/lq/rP3zRQ=",
@@ -152,7 +143,7 @@
         "type": "github"
       }
     },
-    "nixpkgs_3": {
+    "nixpkgs_2": {
       "locked": {
         "lastModified": 1767313136,
         "narHash": "sha256-16KkgfdYqjaeRGBaYsNrhPRRENs0qzkQVUooNHtoy2w=",
@@ -171,7 +162,7 @@
     "nt": {
       "inputs": {
         "nix-unit": "nix-unit",
-        "nixpkgs": "nixpkgs_3",
+        "nixpkgs": "nixpkgs_2",
         "systems": "systems_2"
       },
       "locked": {
@@ -191,12 +182,28 @@
     "root": {
       "inputs": {
         "deploy-rs": "deploy-rs",
-        "nixpkgs": "nixpkgs_2",
-        "nixpkgs-unstable": "nixpkgs-unstable",
+        "microvm": "microvm",
+        "nixpkgs": "nixpkgs",
         "nt": "nt",
         "systems": "systems_3"
       }
     },
+    "spectrum": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1759482047,
+        "narHash": "sha256-H1wiXRQHxxPyMMlP39ce3ROKCwI5/tUn36P8x6dFiiQ=",
+        "ref": "refs/heads/main",
+        "rev": "c5d5786d3dc938af0b279c542d1e43bce381b4b9",
+        "revCount": 996,
+        "type": "git",
+        "url": "https://spectrum-os.org/git/spectrum"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://spectrum-os.org/git/spectrum"
+      }
+    },
     "systems": {
       "locked": {
         "lastModified": 1681028828,

flake.nix

@@ -16,13 +16,12 @@
 
   inputs = {
     systems.url = "github:nix-systems/default";
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
-    nt.url = "github:cry128/nt";
 
-    home-manager = {
-      url = "github:nix-community/home-manager/release-25.11";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
+    # WARNING: nixpkgs is ONLY included so flakes using Cerulean can
+    # WARNING: force Cerulean's inputs to follow a specific revision.
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
+
+    nt.url = "github:cry128/nt";
 
     deploy-rs = {
       url = "github:serokell/deploy-rs";
@@ -36,14 +35,13 @@
   };
 
   outputs = {
-    nixpkgs,
+    self,
     nt,
     ...
   } @ inputs:
     import ./cerulean
     {
-      inherit inputs;
-      inherit (nixpkgs) lib;
+      inherit inputs self nt;
       inherit (nt) mix;
     };
 }