DLC model

Purpose: Define how paid premium scenario-pack expansions are produced, shipped, and unlocked — without any of their content entering the public, open-source repository. This is the contract between the public repo (open core) and the private DLC repo (paid content).

The distribution model in one picture

  GitHub (public, open source)          Steam (paid)                Private repo
  ────────────────────────────          ────────────                ───────────────
  ConversationSimulator/                 Base app — $9.99            ConversationSimulator-DLC/
   • engine (Apache-2.0)         ───▶     (packaged build of ───┐     • premium pack YAML
   • 4 official packs (CC BY 4.0)         the open source)      │     • pack art / audio
   • docs, this contract                                        │     • pack-build script
   • DLC ownership integration           Premium DLC packs  ◀───┘  (never merged to public)
   • DLC depot VDF template               (one Steam DLC per        │
                                          expansion pack)   ◀───────┘  built + uploaded from here

Three channels, one honest story:

GitHub — free. The full source builds and runs at zero cost. Nothing here is paid or proprietary except the pointer to DLC (App IDs, ownership checks).
Steam base app — $9.99. A packaged build of this same open source. Buying it funds development; it does not unlock anything the source build lacks.
Steam DLC — paid, private-sourced. Premium expansion packs, authored in the private repo, sold only as Steam DLC.

Invariant: the open core never shrinks. A pack that is free and open today is never relocked as paid DLC. DLC is only ever additional content.

What lives where

Artifact	Public repo (`ConversationSimulator`)	Private repo (`ConversationSimulator-DLC`)
Engine, app, official free packs, docs	✅	—
DLC ownership check (Steamworks integration)	✅	—
DLC depot VDF template (`steam/depot_dlc_scenariopacks.vdf.tpl`)	✅	—
Premium pack content (scenarios, NPCs, rubrics, art, audio)	❌ never	✅
Premium pack build/packaging + Steam upload workflow	—	✅
DLC App IDs / depot IDs	✅ (as CI variables, non-secret)	✅

The public repo carries the contract — the integration points and the depot template — but no DLC content. The guarantee is repo separation: premium pack content only ever exists in the private repo, so it cannot enter a public commit or a base depot built from this repo. .gitignore guards against a stray local copy being committed; the CI depot audit catches weights, binaries, and secrets in staged depots but cannot itself tell a premium pack from a free one — both are declarative YAML + assets — so it is not the control that keeps premium content out. Keeping that content in the private repo entirely is.

The private repo: `ConversationSimulator-DLC`

A separate private GitHub repository owned by Outright Mental. Its layout mirrors the public pack layout so packs validate against the same open schemas:

ConversationSimulator-DLC/
  packs/
    advanced-professional-skills/     # one directory per premium expansion pack
      manifest.yaml                   # id: com.outrightmental.dlc.advanced_professional_skills
      scenarios/  npcs/  rubrics/  safety/  scenes/
    extended-language-course/
    ...
  scripts/build-dlc-depot.sh          # validates packs + stages Steam depot content
  .github/workflows/dlc-steam-deploy.yml
  STEAM_DLC_REGISTRY.md               # DLC App ID ↔ pack id ↔ depot id mapping

Rules for the private repo:

Every premium pack is declarative YAML + static assets only — no executable code, exactly like public packs. It must pass convsim validate-pack with zero errors and the same safety review as any Outright Mental-distributed pack.
Premium packs carry a proprietary license identifier in their manifest, not CC BY 4.0. They may not be redistributed outside Steam DLC.
The private repo consumes the public repo’s open schemas and validator as a dependency; it never forks the engine.

How a premium pack becomes Steam DLC

Steam models DLC as a separate product (its own App ID) tied to the base app, with its own depot for content. For each premium expansion pack:

Register the DLC in Steamworks: a new DLC App ID and content depot associated with the base app. Set its price.
Author + validate the pack in the private repo.
Build + upload the DLC depot from the private repo’s deploy workflow, using the depot VDF template shape defined in the public repo (steam/depot_dlc_scenariopacks.vdf.tpl), pointed at the DLC depot ID and the private pack content.
Install location. When a player owns and installs the DLC, Steam places its content under the DLC depot’s install path inside the base app’s install directory (e.g. dlc/<dlc_pack_id>/). The base app discovers premium packs there at startup.

DLC content is excluded from the base app’s depots — the base app never bundles paid packs. The DLC depot is uploaded separately, only from the private repo.

How the app unlocks owned DLC

The base app is the same open-source binary for everyone; DLC packs are gated at runtime by Steam ownership, not by shipping different builds.

apps/desktop/src-tauri/src/steam.rs — SteamRuntime::is_dlc_installed(dlc_app_id) wraps steamworks::Apps::is_dlc_installed(AppId). Returns false when Steam is disabled, not running, or the DLC is not owned.
steam_is_dlc_installed Tauri command exposes it to the front end.
apps/web/src/hooks/useSteamDlc.ts — resolves to “not owned” outside Tauri/Steam, so the open-source browser build behaves identically.
Pack library — owned premium packs load as playable; unowned ones show as available to buy with a link to the DLC’s Steam store page.

Ownership resolution is offline-friendly: once Steam has confirmed ownership and the DLC is installed locally, play needs no network — consistent with the local-first guarantee. No conversation content, transcript, or DLC-usage event is ever sent to Steam or any server (see Steam integration).

Refunds, safety, and ratings

Refunds: Steam’s standard refund policy (2-week / 2-hour window) applies to the base game and every DLC. A DLC removed for a content-policy violation triggers a refund to all purchasers regardless of the window.
Safety: DLC packs are bound by the same non-overridable safety rules as every pack — minors and self-harm crisis content are handled identically and cannot be weakened by a paid pack. DLC packs must not exceed the PG-13 cap.
Ratings: base game and all DLC stay within the PG–PG-13 boundaries declared on the store page. A DLC that would change the rating requires a fresh IARC review.

Guardrails (must stay true)

No premium/DLC pack content is ever committed to the public repository.
The base app builds and runs fully from open source with all four official packs free; DLC absence is never an error or a nag beyond a normal “available to buy” affordance.
The DLC ownership check degrades to “not owned” in every non-Steam context.
No in-app payment UI, Steam Wallet, or microtransaction system — paid content is delivered only through Steam’s DLC storefront.