When the name is not the wire

The web taught us a bad habit: treat the human-readable path as the thing itself. Rename the path, and every dependent that baked the string becomes a broken promise.

This essay is the technical companion to When renaming a page breaks half your docs. Full diagrams and the adoption ladder live in the docs: Navigating by content.

Two naming problems, not one solution

Named Data Networking (NDN) and similar information-centric designs attack location: fetch by name without depending on a host IP. Dr. Lan Wang’s Networking Research Lab at the University of Memphis is one known node in that NSF-shaped research community. NDN routers care whether an Interest can be satisfied from a nearby cache. They do not rewrite your Markdown when /docs/v1 becomes /docs/v2. Those are different names.

Application reverse-dependency tracking attacks semantic life cycle: when a symbol, path, or doc label changes, who breaks? Kythe/Sourcegraph graphs, OpenRewrite recipes, Unison’s content-addressed definitions, and a humble producer-owned CONSUMERS.md all live here.

flowchart TB
  subgraph app [Application graph]
    Labels[Human labels / URLs]
    Graph[AST + docs + manifests]
    Consumers[Reverse consumers]
    Labels --> Graph --> Consumers
  end
  subgraph net [Network delivery]
    Name[Content or hierarchical name]
    Cache[Nearest cache]
    Name --> Cache
  end
  app -.->|opaque string| net

Architecturally orthogonal. Complementary in UX: both serve “I should not have to care where it lives or what we currently call it,” if we stack them instead of collapsing them.

The stack

1. Content-addressed identity (CAS) — bind to hash(bytes) (or a graph node id). Moves and renames with identical content do not break fetch: $Hash(Bytes_{old}) = Hash(Bytes_{new})$.
2. Mutable human pointer — a stable semantic name resolves to the current hash when content updates. Without this, CAS freezes you on $v1$ because $Hash(Bytes_{v1}) \neq Hash(Bytes_{v2})$.
3. Reverse consumer graph — producers list who still holds labels (CONSUMERS.md). Agents search those trees instead of guessing.
4. Absorb layer — redirects, Antora aliases, “cool URIs don’t change.” Required on today’s IP web.

flowchart LR
  C[Consumer] -->|prefer| H[Content hash]
  C -->|or| P[Mutable pointer]
  P --> H
  H --> M[Metadata: path, aliases]
  R[CONSUMERS.md] -->|label moves| C

Unison shows the destination for code identity. connectome-fs aims at the filesystem and association plane underneath many languages and non-code artifacts — path as projection, graph as truth. See its explanation Navigating by content beside Semantic change units.

Near-term practice

Until CAS is ordinary:

• Prefer aliases over renames for anything public.
• Put reverse deps on the producer.
• Record coupling type (package vs URL vs Antora vs secret name).
• Teach tools and agents: read the list, search those trees, open PRs.
• Leave redirects forever.

Pretty URLs stay. They just stop being the wire.