diff --git a/.github/workflows/map-artifact.yml b/.github/workflows/map-artifact.yml
new file mode 100644
index 0000000..7fc2e6e
--- /dev/null
+++ b/.github/workflows/map-artifact.yml
@@ -0,0 +1,69 @@
+name: map-artifact
+
+on:
+  push:
+    branches: [main]
+    tags: ["v*"]
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  build-map-artifact:
+    name: Build compiled JSON-IR map artifact
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+      - name: Checkout interscript-ts
+        run: git clone --depth=1 --branch main https://github.com/interscript/interscript-ts.git ../interscript-ts
+      - uses: actions/setup-node@v7
+        with:
+          node-version: "22"
+      - name: Install + build TS converter
+        run: |
+          cd ../interscript-ts
+          npm ci
+          npm run build
+      - name: Build map artifact directory
+        run: npx -y tsx scripts/build-json-ir-artifact.mjs ../interscript-ts dist/interscript-maps-ir
+      - name: Validate artifact shape
+        run: |
+          test -f dist/interscript-maps-ir/manifest.json
+          test -f dist/interscript-maps-ir/SHA256SUMS
+          test "$(find dist/interscript-maps-ir/maps -name '*.json' | wc -l | tr -d ' ')" = "289"
+          node - <<'NODE'
+          import { createHash } from 'node:crypto'
+          import { readFileSync } from 'node:fs'
+          for (const line of readFileSync('dist/interscript-maps-ir/SHA256SUMS', 'utf8').trim().split('\n')) {
+            const [expected, path] = line.split(/  /)
+            const actual = createHash('sha256').update(readFileSync(`dist/interscript-maps-ir/${path}`)).digest('hex')
+            if (actual !== expected) throw new Error(`${path}: sha256 mismatch`)
+          }
+          NODE
+      - name: Pack artifact
+        run: |
+          version="$([ "${GITHUB_REF_TYPE}" = "tag" ] && echo "${GITHUB_REF_NAME#v}" || echo "${GITHUB_SHA::12}")"
+          mkdir -p dist/release
+          tar -C dist/interscript-maps-ir -czf "dist/release/interscript-maps-ir-${version}.tar.gz" .
+          node - <<'NODE'
+          import { createHash } from 'node:crypto'
+          import { readFileSync, writeFileSync } from 'node:fs'
+          const version = process.env.GITHUB_REF_TYPE === "tag"
+            ? process.env.GITHUB_REF_NAME.replace(/^v/, '')
+            : process.env.GITHUB_SHA.slice(0, 12)
+          const name = `interscript-maps-ir-${version}.tar.gz`
+          const sha = createHash('sha256').update(readFileSync(`dist/release/${name}`)).digest('hex')
+          writeFileSync(`dist/release/${name}.sha256`, `${sha}  ${name}\n`)
+          NODE
+      - name: Upload workflow artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: interscript-maps-ir
+          path: dist/release/
+      - name: Attach artifact to GitHub Release
+        if: startsWith(github.ref, 'refs/tags/v')
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: gh release upload "$GITHUB_REF_NAME" dist/release/* --clobber
diff --git a/scripts/build-json-ir-artifact.mjs b/scripts/build-json-ir-artifact.mjs
new file mode 100644
index 0000000..339e035
--- /dev/null
+++ b/scripts/build-json-ir-artifact.mjs
@@ -0,0 +1,76 @@
+#!/usr/bin/env node
+// Build the deployable JSON-IR map artifact from this repository's .isc corpus.
+//
+// Usage:
+//   node scripts/build-json-ir-artifact.mjs <interscript-ts-dir> <out-dir>
+//
+// Output directory layout:
+//   manifest.json
+//   SHA256SUMS
+//   maps/<system>.json
+
+import { createHash } from "node:crypto"
+import { mkdirSync, readFileSync, readdirSync, rmSync, statSync, writeFileSync } from "node:fs"
+import { basename, join, relative, resolve } from "node:path"
+import { pathToFileURL } from "node:url"
+
+const [tsDir, outDir] = process.argv.slice(2)
+if (!tsDir || !outDir) {
+  console.error("usage: build-json-ir-artifact.mjs <interscript-ts-dir> <out-dir>")
+  process.exit(2)
+}
+
+const repoRoot = resolve(import.meta.dirname, "..")
+const mapsDir = join(repoRoot, "maps")
+const outputRoot = resolve(outDir)
+const outputMaps = join(outputRoot, "maps")
+
+const { parseIsc } = await import(pathToFileURL(resolve(tsDir, "src/isc/parser.ts")))
+const { iscToCompiledMap } = await import(pathToFileURL(resolve(tsDir, "src/isc/converter.ts")))
+
+rmSync(outputRoot, { recursive: true, force: true })
+mkdirSync(outputMaps, { recursive: true })
+
+const files = readdirSync(mapsDir)
+  .filter((file) => file.endsWith(".isc"))
+  .sort()
+
+const systems = []
+for (const file of files) {
+  const code = basename(file, ".isc")
+  const source = readFileSync(join(mapsDir, file), "utf8")
+  const doc = parseIsc(source, file)
+  const compiled = iscToCompiledMap(doc)
+  writeFileSync(join(outputMaps, `${code}.json`), `${JSON.stringify(compiled)}\n`)
+  systems.push(code)
+}
+
+const manifest = {
+  schema: "interscript.maps.ir.v1",
+  source: "interscript/maps",
+  generatedAt: new Date().toISOString(),
+  count: systems.length,
+  systems,
+}
+writeFileSync(join(outputRoot, "manifest.json"), `${JSON.stringify(manifest, null, 2)}\n`)
+
+const artifactFiles = []
+function walk(dir) {
+  for (const name of readdirSync(dir).sort()) {
+    const path = join(dir, name)
+    if (statSync(path).isDirectory()) walk(path)
+    else artifactFiles.push(path)
+  }
+}
+walk(outputRoot)
+
+const checksums = artifactFiles
+  .filter((path) => basename(path) !== "SHA256SUMS")
+  .map((path) => {
+    const sha = createHash("sha256").update(readFileSync(path)).digest("hex")
+    return `${sha}  ${relative(outputRoot, path)}`
+  })
+  .join("\n")
+writeFileSync(join(outputRoot, "SHA256SUMS"), `${checksums}\n`)
+
+console.log(`compiled ${systems.length} maps to ${outputRoot}`)