diff --git a/.gitea/workflows/release.yml b/.gitea/workflows/release.yml
new file mode 100644
index 0000000..365b486
--- /dev/null
+++ b/.gitea/workflows/release.yml
@@ -0,0 +1,337 @@
+# Automated release for the deployable ServUO overlay.
+#
+# Trigger: every push to `main` (i.e. every merged PR).
+#
+# Why this exists: the Runic Gateway installer deploys the plugin from a release
+# tarball, not from git — the shard host gets no git and no Gitea credentials
+# (docs/installer/PLAN.md §1, §5 Phase 0.1). Until this workflow, `link` was the
+# only repo that published releases, so there was nothing for the installer to
+# fetch. This is Phase 0 item 1.
+#
+# Flow (two conceptual halves, kept separate on purpose):
+#
+#   ┌── RELEASE ENGINE (language-agnostic) ─────────────────────────────┐
+#   │  reads: latest v* git tag + conventional-commit subjects          │
+#   │  produces: next version, changelog, and (at the end) the release  │
+#   └───────────────────────────────────────────────────────────────────┘
+#   ┌── OVERLAY ADAPTER (the only repo-specific part) ──────────────────┐
+#   │  consumes: the version                                            │
+#   │  produces: runicgateway-overlay-<ver>.tar.gz + SHA256SUMS         │
+#   └───────────────────────────────────────────────────────────────────┘
+#
+# The engine is `link/.gitea/workflows/release.yml`'s, reused as its own header
+# anticipated — the plan and release steps consume only {version, changelog,
+# artifacts} and know nothing about what is inside the artifacts.
+#
+# ── Three differences from link's copy, all forced by this repo ──────────────
+#
+# 1. NO BUILD. The plugin ships as C# source and ServUO compiles it at boot; it
+#    needs ServUO reference assemblies, so there is no way to compile it here.
+#    The build gates are replaced by the structural gates below, which is the
+#    most this repo can honestly assert about an artifact.
+#
+# 2. NO BUMP COMMIT, and so no push to `main`. link has to write the version
+#    into Cargo.toml because the binary embeds it; a tarball embeds nothing but
+#    the manifest.json this job generates, so the git tag IS the version. That
+#    removes a failure mode outright: this workflow never needs `main` to accept
+#    a direct push, so no branch-protection exception is required for it.
+#
+# 3. A MANIFEST. The tarball carries manifest.json — version, commit, declared
+#    protocol version, ServUO compatibility, and a SHA256 for every file. The
+#    installer needs it because the plugin announces no version on the wire and
+#    none is queryable before ServUO boots (PLAN.md §2.6): the manifest is the
+#    only thing that lets the bundle CI verify sidecar/overlay protocol
+#    agreement BEFORE an operator installs the pair (PLAN.md §7.1, gate 1).
+#
+# Version bump (conventional commits since the last v* tag):
+#   feat!: / BREAKING CHANGE  -> major     feat: -> minor     fix|perf: -> patch
+#   nothing releasable        -> no release is cut (a docs:/chore:-only merge
+#                                deliberately does NOT cut one — PLAN.md §7.3)
+#   (first ever run, no tag)  -> releases SEED_VERSION below
+#
+# Prerequisites (Settings → Actions → Secrets on RunicGateway/servuo-plugins):
+#   REGISTRY_TOKEN  — Gitea access token with `write:repository`, to push the
+#                     tag and create the release.
+#   REGISTRY_USER   — the Gitea username that token belongs to.
+#
+# TODO (Phase 0 item 3): once the installer repo's bundle workflow exists, append
+# a final step here that POSTs to its workflow-dispatch endpoint, so a new
+# overlay release recomposes the bundle immediately instead of waiting for the
+# nightly cron (PLAN.md §7.2). Deliberately absent until there is something to
+# dispatch — a step that 404s every release is worse than no step.
+
+name: Release overlay
+
+on:
+  push:
+    branches: [main]
+  workflow_dispatch: {}
+
+concurrency:
+  group: release-overlay
+  cancel-in-progress: false
+
+env:
+  GITEA_HOST: gitea.whitlocktech.com
+  REPO: RunicGateway/servuo-plugins
+  # Artifact naming per PLAN.md §3.
+  ARTIFACT: runicgateway-overlay
+  # Used only for the very first release, when no v* tag exists yet. Matches the
+  # house style set by link (pre-1.0; the release version is independent of the
+  # protocol version, which lives in overlay.toml).
+  SEED_VERSION: "0.1.0"
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out full history (need tags + commit log for the bump)
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      # ── RELEASE ENGINE: decide the next version + changelog ──────────────
+      - name: Plan the release (version + changelog)
+        id: plan
+        run: |
+          set -euo pipefail
+          mkdir -p dist
+          git fetch --tags --force >/dev/null 2>&1 || true
+
+          LAST_TAG="$(git describe --tags --match 'v*' --abbrev=0 2>/dev/null || true)"
+          if [ -n "$LAST_TAG" ]; then RANGE="${LAST_TAG}..HEAD"; else RANGE="HEAD"; fi
+
+          SUBJECTS="$(git log --no-merges --format='%s' $RANGE || true)"
+          BODIES="$(git log --no-merges --format='%B' $RANGE || true)"
+
+          BUMP=none
+          if echo "$BODIES"   | grep -qE 'BREAKING[ -]CHANGE'          ; then BUMP=major; fi
+          if echo "$SUBJECTS" | grep -qE '^[a-z]+(\([^)]+\))?!:'       ; then BUMP=major; fi
+          if [ "$BUMP" = none ] && echo "$SUBJECTS" | grep -qE '^feat(\([^)]+\))?:'      ; then BUMP=minor; fi
+          if [ "$BUMP" = none ] && echo "$SUBJECTS" | grep -qE '^(fix|perf)(\([^)]+\))?:'; then BUMP=patch; fi
+
+          bump() { # <x.y.z> <major|minor|patch> -> bumped
+            IFS=. read -r MA MI PA <<< "$1"
+            case "$2" in
+              major) echo "$((MA+1)).0.0" ;;
+              minor) echo "${MA}.$((MI+1)).0" ;;
+              patch) echo "${MA}.${MI}.$((PA+1))" ;;
+            esac
+          }
+
+          RELEASE=true
+          if [ -z "$LAST_TAG" ]; then
+            VERSION="$SEED_VERSION"                  # first release: seed
+          elif [ "$BUMP" = none ]; then
+            RELEASE=false                            # no feat/fix/breaking since last tag
+            VERSION="${LAST_TAG#v}"
+          else
+            VERSION="$(bump "${LAST_TAG#v}" "$BUMP")"
+          fi
+
+          if git rev-parse -q --verify "refs/tags/v${VERSION}" >/dev/null; then
+            echo "Tag v${VERSION} already exists — nothing to release."
+            RELEASE=false
+          fi
+
+          {
+            echo "## ${ARTIFACT} v${VERSION}"
+            echo
+            FEATS="$(echo "$SUBJECTS" | grep -E '^feat'        || true)"
+            FIXES="$(echo "$SUBJECTS" | grep -E '^(fix|perf)'  || true)"
+            [ -n "$FEATS" ] && { echo "### Features";  echo "$FEATS" | sed 's/^/- /'; echo; }
+            [ -n "$FIXES" ] && { echo "### Fixes";     echo "$FIXES" | sed 's/^/- /'; echo; }
+            echo "### All changes"
+            if [ -n "$LAST_TAG" ]; then echo "Since ${LAST_TAG}:"; fi
+            echo "$SUBJECTS" | sed 's/^/- /'
+          } > dist/CHANGELOG.md
+
+          echo "version=${VERSION}"   >> "$GITHUB_OUTPUT"
+          echo "tag=v${VERSION}"      >> "$GITHUB_OUTPUT"
+          echo "release=${RELEASE}"   >> "$GITHUB_OUTPUT"
+          echo "bump=${BUMP}"         >> "$GITHUB_OUTPUT"
+          echo "==> release=${RELEASE} version=${VERSION} bump=${BUMP} last_tag=${LAST_TAG:-<none>}"
+
+      - name: Install jq
+        if: ${{ steps.plan.outputs.release == 'true' }}
+        run: |
+          set -euo pipefail
+          command -v jq >/dev/null 2>&1 && exit 0
+          SUDO=""; [ "$(id -u)" -ne 0 ] && SUDO="sudo"
+          $SUDO apt-get update -qq
+          $SUDO apt-get install -y -qq --no-install-recommends jq
+
+      # ── OVERLAY ADAPTER: gates ───────────────────────────────────────────
+      # There is no compiler to run, so these assert the things that CAN be
+      # checked without a ServUO tree — and each one has actually been a way to
+      # ship a broken overlay:
+      #
+      #   • overlay/ mirrors the server root; if Bridge.cfg or the Bridge scripts
+      #     go missing the deploy silently no-ops (PLAN.md §2.1).
+      #   • overlay/Scripts/Scripts.csproj is Phase 0 of the plugin itself — it
+      #     overwrites a stock file to fix ServUO's silent script-build bug. An
+      #     overlay shipped without it installs code that never compiles, and
+      #     ServUO reports success anyway.
+      #   • a malformed .patch is invisible until an operator runs the patch tier
+      #     on their live shard. `git apply --stat` parses the diff without
+      #     needing the target files present.
+      #   • each patch's companion .cs must exist, since it references symbols
+      #     the patch introduces and is meaningless without it (PLAN.md §2.2).
+      - name: Validate the overlay and patch tier
+        if: ${{ steps.plan.outputs.release == 'true' }}
+        run: |
+          set -euo pipefail
+          fail() { echo "::error::$*"; exit 1; }
+
+          [ -f overlay/Config/Bridge.cfg ]        || fail "overlay/Config/Bridge.cfg is missing"
+          [ -f overlay/Scripts/Scripts.csproj ]   || fail "overlay/Scripts/Scripts.csproj is missing (the silent-build-bug fix)"
+          [ -d overlay/Scripts/Custom/Bridge ]    || fail "overlay/Scripts/Custom/Bridge/ is missing"
+
+          CS_COUNT="$(find overlay/Scripts/Custom/Bridge -name '*.cs' | wc -l)"
+          [ "$CS_COUNT" -gt 0 ] || fail "overlay/Scripts/Custom/Bridge/ contains no .cs files"
+          echo "overlay: ${CS_COUNT} bridge script(s)"
+
+          for p in patches/*.patch; do
+            [ -e "$p" ] || fail "patches/ contains no .patch files"
+            echo "--- ${p}"
+            git apply --stat "$p" || fail "${p} is not a parseable unified diff"
+          done
+
+          # Companion files that can only be copied after their patch lands.
+          for f in patches/BridgeVendorSale.cs patches/BridgeModerationAudit.cs; do
+            [ -f "$f" ] || fail "${f} is missing (a patch's companion source)"
+          done
+
+          [ -f overlay.toml ] || fail "overlay.toml is missing (protocol + ServUO declarations)"
+
+      # ── OVERLAY ADAPTER: stage, manifest, package ────────────────────────
+      # The tarball has a FIXED top-level directory (runicgateway-overlay/), not a
+      # versioned one: the installer extracts and then looks for overlay/,
+      # patches/ and manifest.json at known paths, and a version-dependent prefix
+      # would make it parse the very version it is trying to read.
+      #
+      # tar flags pin ownership, mtime and member order so the same tree produces
+      # a byte-identical tarball — a checksum that changes only when content
+      # changes is worth more than one that changes every run.
+      - name: Build manifest.json and the release tarball
+        if: ${{ steps.plan.outputs.release == 'true' }}
+        run: |
+          set -euo pipefail
+          VERSION="${{ steps.plan.outputs.version }}"
+          STAGE="dist/stage/${ARTIFACT}"
+
+          mkdir -p "${STAGE}"
+          cp -r overlay  "${STAGE}/overlay"
+          cp -r patches  "${STAGE}/patches"
+
+          # Declarations from overlay.toml. Read, don't hardcode — the point of
+          # that file is that the protocol number lives in one place.
+          PROTOCOL="$(grep -m1 -E '^protocol[[:space:]]*=' overlay.toml | sed -E 's/[^0-9]//g')"
+          MIN_SERVUO="$(grep -m1 -E '^min_servuo_version[[:space:]]*=' overlay.toml | sed -E 's/.*"([^"]+)".*/\1/')"
+          PATCHED_AGAINST="$(grep -m1 -E '^patches_verified_against[[:space:]]*=' overlay.toml | sed -E 's/.*"([^"]+)".*/\1/')"
+          [ -n "$PROTOCOL" ] || { echo "::error::could not read protocol from overlay.toml"; exit 1; }
+          [ -n "$MIN_SERVUO" ] || { echo "::error::could not read min_servuo_version from overlay.toml"; exit 1; }
+          [ -n "$PATCHED_AGAINST" ] || { echo "::error::could not read patches_verified_against from overlay.toml"; exit 1; }
+          echo "==> protocol=${PROTOCOL} min_servuo=${MIN_SERVUO} patches_verified_against=${PATCHED_AGAINST}"
+
+          # Per-file SHA256 of everything shipped, as a {path: sha} object. The
+          # installer records these in install.json so a later `doctor` can tell
+          # "operator edited a deployed file" from "the overlay drifted".
+          # The `\*?` is not paranoia: sha256sum marks binary mode by prefixing the
+          # path with `*` (`<hash> *path`) instead of the two-space text-mode
+          # separator. Coreutils on Linux defaults to text mode, but a build host
+          # that doesn't would otherwise put a leading `*` on EVERY key here and
+          # silently produce a manifest whose paths match nothing.
+          FILES="$(cd "${STAGE}" \
+            && find overlay patches -type f -print0 | LC_ALL=C sort -z | xargs -0 sha256sum \
+            | jq -R -s '
+                split("\n") | map(select(length > 0))
+                | map(capture("^(?<sha>[0-9a-f]+)[ \t]+\\*?(?<path>.+)$"))
+                | map({ (.path): .sha }) | add')"
+
+          jq -n \
+            --arg    component "servuo-plugins-overlay" \
+            --arg    version   "${VERSION}" \
+            --arg    commit    "${GITHUB_SHA}" \
+            --arg    repo      "${REPO}" \
+            --argjson protocol "${PROTOCOL}" \
+            --arg    min_servuo "${MIN_SERVUO}" \
+            --arg    patched_against "${PATCHED_AGAINST}" \
+            --argjson files    "${FILES}" \
+            '{
+               component: $component,
+               version:   $version,
+               commit:    $commit,
+               repo:      $repo,
+               protocol:  $protocol,
+               servuo: {
+                 min_version:              $min_servuo,
+                 patches_verified_against: $patched_against
+               },
+               files: $files
+             }' > "${STAGE}/manifest.json"
+
+          echo "----- manifest.json (files elided) -----"
+          jq 'del(.files) + {file_count: (.files | length)}' "${STAGE}/manifest.json"
+
+          TARBALL="${ARTIFACT}-${VERSION}.tar.gz"
+          tar --sort=name --mtime='UTC 1970-01-01' \
+              --owner=0 --group=0 --numeric-owner \
+              -czf "dist/${TARBALL}" -C dist/stage "${ARTIFACT}"
+
+          ( cd dist && sha256sum "${TARBALL}" > SHA256SUMS )
+          echo "tarball=${TARBALL}" >> "$GITHUB_OUTPUT"
+          ls -l dist && echo "----" && cat dist/SHA256SUMS
+        id: package
+
+      # ── RELEASE ENGINE: tag ──────────────────────────────────────────────
+      # Tag only — no bump commit, so `main` is never pushed to (see header).
+      - name: Push the release tag
+        if: ${{ steps.plan.outputs.release == 'true' }}
+        env:
+          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
+          REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
+        run: |
+          set -euo pipefail
+          TAG="${{ steps.plan.outputs.tag }}"
+          # Secrets can arrive with a trailing newline (depending on how they were
+          # pasted); a stray CR/LF corrupts the remote URL ("credential url cannot
+          # be parsed"). Strip line breaks before building the URL.
+          CI_USER="$(printf '%s' "${REGISTRY_USER}" | tr -d '\r\n')"
+          CI_TOKEN="$(printf '%s' "${REGISTRY_TOKEN}" | tr -d '\r\n')"
+          git config user.name  "servuo-plugins-ci"
+          git config user.email "ci@whitlocktech.com"
+          git remote set-url origin \
+            "https://${CI_USER}:${CI_TOKEN}@${GITEA_HOST}/${REPO}.git"
+          git tag "${TAG}"
+          git push origin "${TAG}"
+
+      # ── RELEASE ENGINE: create the Gitea release + upload assets ─────────
+      - name: Create Gitea release and upload assets
+        if: ${{ steps.plan.outputs.release == 'true' }}
+        env:
+          REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
+        run: |
+          set -euo pipefail
+          TAG="${{ steps.plan.outputs.tag }}"
+          TARBALL="${{ steps.package.outputs.tarball }}"
+          API="https://${GITEA_HOST}/api/v1/repos/${REPO}"
+          BODY="$(cat dist/CHANGELOG.md)"
+          # Same newline hygiene as the tag step: a stray CR/LF in the token would
+          # corrupt the Authorization header.
+          CI_TOKEN="$(printf '%s' "${REGISTRY_TOKEN}" | tr -d '\r\n')"
+
+          REL_ID="$(curl -sSf -X POST "${API}/releases" \
+            -H "Authorization: token ${CI_TOKEN}" \
+            -H "Content-Type: application/json" \
+            -d "$(jq -n --arg tag "$TAG" --arg body "$BODY" \
+                   '{tag_name:$tag, name:$tag, body:$body, draft:false, prerelease:false}')" \
+            | jq -r '.id')"
+          echo "Created release ${TAG} (id=${REL_ID})"
+
+          for f in "${TARBALL}" SHA256SUMS; do
+            curl -sSf -X POST "${API}/releases/${REL_ID}/assets?name=${f}" \
+              -H "Authorization: token ${CI_TOKEN}" \
+              -F "attachment=@dist/${f}" >/dev/null
+            echo "  uploaded ${f}"
+          done
diff --git a/.gitignore b/.gitignore
index 1a6da89..f47f46a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,4 @@ obj/
 *.exe
 *.pdb
 *.log
+dist/
diff --git a/README.md b/README.md
index b14ea23..91aac1a 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,8 @@ integration guide, protocol spec, research — with full history preserved).
 | `patches/` | Unified diffs against stock ServUO for files we must modify rather than add. |
 | `tools/` | Never deployed. Test scaffolding (C# probes + PowerShell stub sidecars) and anything else that must not reach a server. |
 | `deploy.ps1` | Copies `overlay/` into a server root. `-Verify` diffs instead of writing. |
+| `overlay.toml` | Release metadata: the wire-protocol version this overlay speaks, and its ServUO compatibility. Read by CI into the release manifest — see [Releases](#releases). |
+| `.gitea/workflows/release.yml` | Publishes `runicgateway-overlay-<ver>.tar.gz` on every merge to `main`. |
 | [INTEGRATION.md](https://gitea.whitlocktech.com/RunicGateway/docs/src/branch/main/link/INTEGRATION.md) | **Website integration guide** — the WebSocket feed, REST endpoints, auth, event catalog, and examples. |
 | [PLAN.md](https://gitea.whitlocktech.com/RunicGateway/docs/src/branch/main/link/PLAN.md) | Implementation plan, measured performance budget, and the full data catalog. |
 | [RESEARCH.md](https://gitea.whitlocktech.com/RunicGateway/docs/src/branch/main/link/RESEARCH.md) | Original source-level research. Partly superseded — see the corrections table in `PLAN.md` §8. |
@@ -41,8 +43,9 @@ The two are deployed **together** but built **independently**:
 
 - **This plugin** is deployed as *source* — `deploy.ps1` copies `overlay/` into the ServUO server
   root, and ServUO compiles it at boot (`Scripts.csproj`; see [Phase 0](#phase-0--what-it-fixes)).
-  There is no separate build artifact and no CI build — it cannot be compiled standalone without the
-  ServUO reference assemblies.
+  There is **no CI build** — it cannot be compiled standalone without the ServUO reference
+  assemblies. CI does publish a *source* tarball for the installer to fetch; see
+  [Releases](#releases).
 - **The sidecar** is a standalone Rust binary, released from its own repo.
 
 The **only** coupling is the loopback JSON protocol (the shard dials out to the sidecar on
@@ -59,6 +62,54 @@ without the sidecar running.
 .\deploy.ps1 -ServerPath <servuo>           # write
 ```
 
+`deploy.ps1` is the **developer-facing** tool and stays that way. Operators get the
+[Runic Gateway installer](https://gitea.whitlocktech.com/RunicGateway/installer), which does the
+same sync cross-platform from the release tarball below.
+
+## Releases
+
+Every merge to `main` that carries a releasable conventional commit (`feat:`, `fix:`, `perf:`, or a
+breaking change — a `docs:`/`chore:`-only merge deliberately cuts nothing) publishes a Gitea release:
+
+```
+runicgateway-overlay-<ver>.tar.gz
+└── runicgateway-overlay/
+    ├── manifest.json
+    ├── overlay/        # exactly what deploy.ps1 would copy
+    └── patches/        # the opt-in stock-file diffs + their companion sources
+SHA256SUMS
+```
+
+This is a **source** tarball, not a build — nothing here is compiled. It exists so the installer can
+deploy the plugin onto a shard host that has no git and no Gitea credentials.
+
+`manifest.json` is what makes the tarball self-describing:
+
+```json
+{
+  "component": "servuo-plugins-overlay",
+  "version": "0.1.0",
+  "commit": "968b526…",
+  "protocol": 3,
+  "servuo": { "min_version": "57.4", "patches_verified_against": "57.4" },
+  "files": { "overlay/Config/Bridge.cfg": "32718424…", … }
+}
+```
+
+- **`protocol`** comes from `overlay.toml` and is the plugin half of the compatibility contract. The
+  plugin announces no version on the wire and none is queryable before ServUO boots, so this
+  declaration is the only way the installer can check it against the sidecar's `PROTOCOL_VERSION`
+  *before* an operator installs the pair. **When the protocol changes, bump it in the same PR that
+  changes the emitters.**
+- **`files`** carries a SHA256 per shipped file, so a deployment can later tell "an operator edited
+  this" from "the overlay moved on".
+
+The version is derived from git tags — there is no version to maintain by hand and no bump commit,
+so this workflow never pushes to `main`.
+
+The tarball is byte-reproducible for a given tree (`tar --sort=name`, pinned mtime and ownership), so
+its checksum changes only when its contents do.
+
 ## Status
 
 | Phase | State |
diff --git a/overlay.toml b/overlay.toml
new file mode 100644
index 0000000..034eae3
--- /dev/null
+++ b/overlay.toml
@@ -0,0 +1,42 @@
+# Release metadata for the deployable overlay.
+#
+# Consumed by .gitea/workflows/release.yml, which folds these values into the
+# manifest.json shipped inside runicgateway-overlay-<ver>.tar.gz. The Runic
+# Gateway installer reads that manifest to decide what it is deploying and
+# whether it is compatible with the sidecar it is about to install
+# (docs/installer/PLAN.md §5 Phase 0, §7.1).
+#
+# There is deliberately NO version key here. The release version is derived from
+# git tags and conventional commits by the release workflow, so there is no bump
+# commit to keep in sync and no way for this file to disagree with the tag.
+
+# ── The loopback wire-protocol version this overlay speaks ───────────────────
+#
+# This is the plugin half of the compatibility contract. It MUST equal the
+# sidecar's PROTOCOL_VERSION (link/sidecar/src/main.rs) for a deployment to
+# work: the sidecar rejects a mismatch with 409 rather than mis-parsing.
+#
+# The C# plugin has no queryable version before ServUO boots — it does not
+# announce one on the wire — so this declaration is the only thing that lets the
+# installer's bundle CI check the pair BEFORE an operator installs them
+# (docs/installer/PLAN.md §2.6, §7.1 gate 1). Keeping it honest is therefore a
+# manual duty: when the protocol changes, bump it here in the same PR that
+# changes the emitters, exactly as link bumps PROTOCOL_VERSION.
+#
+# Current: 3 — see docs/link/v3.md (world.ruleset, points.board, vendor.listing).
+protocol = 3
+
+# ── ServUO compatibility ─────────────────────────────────────────────────────
+#
+# The base overlay (Config/Bridge.cfg + Scripts/Custom/Bridge/*.cs) only ADDS
+# files and is expected to work on any reasonably current ServUO. This is the
+# oldest version it is known good on.
+min_servuo_version = "57.4"
+
+# The patches/ tier is a different matter: those are unified diffs against STOCK
+# ServUO files, so they are verified against exactly one version and nothing
+# else. On any other version the installer skips the whole tier with a warning
+# and completes the base install (docs/installer/PLAN.md §1, §2.2) — losing
+# vendor.sale events and in-game moderation-audit forwarding, but never
+# half-patching an unknown tree.
+patches_verified_against = "57.4"