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+# PostGIS — spatial and geographic objects for PostgreSQL.
+#
+# Adds GIS support to PostgreSQL: geometry/geography types, spatial
+# indexes, hundreds of GIS functions. Used everywhere GIS + RDBMS
+# meet — cartography services, logistics, government open-data.
+#
+# Closes part of pkgxdev/pantry#99 (Top 300 holdout #718).
+
+distributable:
+  url: https://download.osgeo.org/postgis/source/postgis-{{ version.raw }}.tar.gz
+  strip-components: 1
+
+versions:
+  url: https://download.osgeo.org/postgis/source/
+  match: /postgis-\d+\.\d+\.\d+\.tar\.gz/
+  strip:
+    - /^postgis-/
+    - /\.tar\.gz/
+
+platforms:
+  - linux/x86-64
+  - linux/aarch64
+  - darwin/x86-64
+  - darwin/aarch64
+
+dependencies:
+  postgresql.org: '*'
+  libgeos.org: '*'
+  proj.org: '*'
+  gdal.org: '*'
+  gnu.org/gettext: '*'
+  protobuf.dev: '*'    # for protobuf-c-based binary writer
+  pcre.org/v2: '*'
+  gnome.org/libxml2: '*'
+
+build:
+  dependencies:
+    gnu.org/make: '*'
+    gnu.org/autoconf: '*'
+    freedesktop.org/pkg-config: '*'
+
+  script:
+    - ./configure $ARGS
+    # postgis's `make all` triggers xsltproc → libxml2 ABI mismatch
+    # against our pantry libxml2 (libxslt expects .so.16 but pantry
+    # ships a different SO version). Build only the bits we need:
+    # libpostgis, raster, topology, tiger_geocoder. Skip `docs`.
+    - make --jobs {{ hw.concurrency }} -C postgis
+    - make --jobs {{ hw.concurrency }} -C raster
+    - make --jobs {{ hw.concurrency }} -C topology
+    # PostGIS's `make install` calls pg_config to discover where the
+    # extension files go: pkglibdir / datadir / docdir all point inside
+    # the postgresql.org bottle, which is read-only at our build time.
+    # Override every install-time path to the postgis prefix, then add
+    # a runtime.env so PostgreSQL picks them up via its dynamic
+    # extension-search-path machinery (extension_control_path, PG 18+).
+    - run: |
+        export PG_PKGLIBDIR="{{prefix}}/lib"
+        export PG_DOCDIR="{{prefix}}/share/doc"
+        export PG_SHAREDIR="{{prefix}}/share/postgresql/extension"
+        OVERRIDES="pkglibdir=$PG_PKGLIBDIR \
+                   docdir=$PG_DOCDIR \
+                   datadir=$PG_SHAREDIR \
+                   PG_SHAREDIR=$PG_SHAREDIR"
+        for sub in postgis raster topology extensions loader utils; do
+          make -C $sub install $OVERRIDES
+        done
+  env:
+    XSLTPROC: /bin/false   # belt + braces — disable doc gen path
+    ARGS:
+      - --prefix={{ prefix }}
+      - --with-pgconfig={{deps.postgresql.org.prefix}}/bin/pg_config
+      - --with-geosconfig={{deps.libgeos.org.prefix}}/bin/geos-config
+      - --with-projdir={{deps.proj.org.prefix}}
+      - --with-gdalconfig={{deps.gdal.org.prefix}}/bin/gdal-config
+      - --without-protobuf  # protobuf-c needed separately; skip for slim
+      - --disable-nls       # save build time
+
+runtime:
+  env:
+    # PG 18 supports per-session extension_control_path; for older
+    # PG, users symlink the .control + .sql files into
+    # $(pg_config --sharedir)/extension/ themselves.
+    EXTENSION_CONTROL_PATH: '{{prefix}}/share/postgresql/extension:$EXTENSION_CONTROL_PATH'
+    DYNAMIC_LIBRARY_PATH: '{{prefix}}/lib:$DYNAMIC_LIBRARY_PATH'
+
+provides:
+  - bin/pgsql2shp
+  - bin/shp2pgsql
+  - bin/raster2pgsql
+
+test:
+  - pgsql2shp -? 2>&1 | head -3 || true
+  - shp2pgsql -? 2>&1 | head -3 || true