Windows Development Environments

PostGIS has two maintained Windows build surfaces:

• The MSYS2 GitHub Actions job in .github/workflows/msys.yml.
• The Winnie Jenkins scripts under ci/winnie/.

Use those files as the current source of truth when checking Windows-specific build behavior. The retired Trac pages record older MinGW, MinGW-w64, MSYS, and MSVC recipes from the PostGIS 1.x and 2.x packaging era. They are useful for understanding historical packaging constraints, but they should not be used as current setup instructions without checking the live build scripts first.

The GitHub Actions job uses msys2/setup-msys2 and installs dependencies with the MSYS2 package manager instead of hand-building GEOS, PROJ, GDAL, libxml2, CUnit, PostgreSQL, and gettext from source. At the time of this note the active matrix entry is clang64; older mingw64 and ucrt64 entries are kept in the workflow as comments.

The job initializes a temporary PostgreSQL cluster, runs ./autogen.sh, configures PostGIS with the MSYS2 pg_config, builds, and runs make check. When changing Windows-sensitive build code, compare the local change against that workflow before reviving an old Trac command line.

The Winnie scripts are the long-running Windows packaging and regression-test surface. Shared configuration lives in ci/winnie/winnie_common.sh, including dependency versions, PATH, PKG_CONFIG_PATH, PROJ_LIB, PROJ_PATH, and the MSYS2_ARG_CONV_EXCL path-conversion guard.

Use Winnie when the question is about release packaging, dependency bundles, or the Windows jobs represented on the project CI inventory. Use the MSYS2 GitHub Actions workflow when the question is about the lightweight pull-request build.

Older Windows build notes in the retired Trac wiki covered MinGW-w64, MSYS 1.x, MSVC, and NSIS packaging for the PostGIS 1.x and 2.x release era. They assumed SourceForge-era toolchain archives, PostgreSQL 9.x, GCC 4.x, GDAL 1.x, GEOS 3.3/3.4, PROJ 4.x, DocBook XSL 1.76, source-built dependency prefixes, and hand-maintained installer payloads.

Those details are historical context, not current setup guidance. Their durable lesson is that Windows release packaging needs an explicit dependency bundle, installer payload list, and regression-test environment. In the current repository, those responsibilities belong to Winnie and the MSYS2 workflow, not to standalone wiki recipes.

Do not republish the old commands as current instructions. Current Windows fixes should update the relevant MSYS2 workflow, Winnie build/package/regression script, or shared build logic, then document any durable rule here.