den.ctx

Source

modules/context/types.nix — modules/context/os.nix

den.ctx

Type: lazyAttrsOf ctxType

A map of context type names to context type definitions. Each context type defines how data flows through the evaluation pipeline.

Context Type Options

Each den.ctx.<name> has:

description

Type: str

Human-readable description of this context type.

_ (alias: provides)

Type: attrsOf providerType

Maps context names to provider functions. When this context is processed, each provider is called with the current context data and returns aspect fragments.

den.ctx.host._.host = { host }:
  parametric.fixedTo { inherit host; } den.aspects.${host.aspect};

into

Type: lazyAttrsOf (functionTo (listOf raw))

Maps other context type names to transformation functions. Each function takes the current context data and returns a list of new context values.

den.ctx.host.into.user = { host }:
  map (user: { inherit host user; }) (lib.attrValues host.users);

meta.adapter

Type: nullOr (functionTo raw)

An adapter that controls how aspects are resolved within this context. Set on a context node to filter or transform aspects transitively during resolution.

den.ctx.host.meta.adapter = inherited:
  den.lib.aspects.adapters.filter (a: a.name != "unwanted") inherited;

The adapter composes with aspect-level meta.adapter values — context adapters are outermost, aspect adapters are innermost.

includes

Aspect includes attached to this context type. Used by batteries to inject behavior at specific pipeline stages.

modules

Additional modules merged into the resolved output.

Built-in Context Types

den.ctx.host

Context data: { host }

Produced for each den.hosts.<system>.<name> entry.

Providers:

• _.host — fixedTo { host } on the host’s aspect.
• _.user — atLeast on the host’s aspect with { host, user }.

Transitions:

• into.default — identity (for default aspect).
• into.user — one { host, user } per host.users entry.
• into.hm-host — (from hm-os.nix) if HM enabled and has HM users.
• into.wsl-host — (from wsl.nix) if WSL enabled on NixOS host.
• into.hjem-host — (from hjem-os.nix) if hjem enabled.
• into.maid-host — (from maid-os.nix) if nix-maid enabled.

den.ctx.user

Context data: { host, user }

Providers:

• _.user — fixedTo { host, user } on the user’s aspect.

Transitions:

• into.default — identity.

den.ctx.home

Context data: { home }

Produced for each den.homes.<system>.<name> entry.

Providers:

• _.home — fixedTo { home } on the home’s aspect.

den.ctx.hm-host

Context data: { host }

Providers:

• provides.hm-host — imports HM OS module.

Transitions:

• into.hm-user — per HM-class user.

den.ctx.hm-user

Context data: { host, user }

Providers:

• _.hm-user — forwards homeManager class to home-manager.users.<userName>.

den.ctx.wsl-host

Context data: { host }

Providers:

• provides.wsl-host — imports WSL module, creates wsl class forward.

Custom Context Types

Define new contexts to extend the pipeline:

{
  den.ctx.gpu = {
    description = "GPU-enabled host";
    _.gpu = { host }: {
      nixos.hardware.nvidia.enable = true;
    };
  };

  den.ctx.host.into.gpu = { host }:
    lib.optional (host ? gpu) { inherit host; };
}