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+# Compose overlay that grafts this Kalamar instance's customizations onto the
+# stock `kalamar` service of KorAP-Docker's compose.yaml, so the instance can
+# be tested locally without changing either the KorAP-Docker or the
+# KorAP-Ingestion project.
+#
+# It is meant to be *layered on top of* the base compose, e.g.:
+#
+#   docker compose -f <base-compose> -f compose.instance.yaml up
+#
+# Requirements:
+#   * KALAMAR_INSTANCE_DIR must be the ABSOLUTE path to this checkout.
+#     Relative bind-mount paths in a compose override resolve against the
+#     project directory (the first -f / the cwd), not against this file, so
+#     the mounts below go through an absolute env var instead.
+#
+# KorAP-Ingestion wires this up automatically; see its `korap` target and pass
+#   make korap KALAMAR_INSTANCE=../Kalamar-Instance-IDS
+#
+# Keep the mount list in sync with what a real deployment overlays (compare the
+# `deliko-*-compose.yml` files in the sibling DeLiKo instance).
+services:
+  kalamar:
+    # This instance serves its corpus release log as Markdown (*.html.md),
+    # which needs a Kalamar with the Markdown renderer (>= v0.66). The base
+    # compose pins an older image, so override it here. Point KALAMAR_IMAGE at
+    # a locally built tag when testing renderer changes:
+    #   make korap KALAMAR_INSTANCE=../Kalamar-Instance-IDS KALAMAR_IMAGE=korap/kalamar:v0.66-alpha-large
+    image: ${KALAMAR_IMAGE:-korap/kalamar:v0.66-alpha}
+    environment:
+      # Use this instance's config verbatim: skip the export-plugin entrypoint
+      # hack, which rewrites /kalamar/kalamar.production.conf in place and would
+      # fight the read-only mount below.
+      KALAMAR_EXPORT: "false"
+    volumes:
+      - ${KALAMAR_INSTANCE_DIR}/kalamar.ids-mannheim.conf:/kalamar/kalamar.production.conf:ro
+      - ${KALAMAR_INSTANCE_DIR}/templates/custom:/kalamar/templates/custom:ro
+      - ${KALAMAR_INSTANCE_DIR}/default.plugins.json:/kalamar/default.plugins.json:ro
+      - ${KALAMAR_INSTANCE_DIR}/public/robots.txt:/kalamar/public/robots.txt:ro