Rasterio 1.2.9 fixes two regressions (one in 1.2.1 and another in 1.2.8) and another pair of bugs. See https://github.com/mapbox/rasterio/blob/master/CHANGES.txt#L15 for the details. The wheels on PyPI contain the same version of GDAL and its dependencies as did the ones for 1.2.8. Unless more regressions are found, this will be the last 1.2.x release.

Head's up: I'd like to make some major changes for the 1.3.0 release. Dropping support for linux systems with glibc older than 2.17 (aka "manylinux2014") will help us upgrade GDAL's dependencies and continue to offer modern and secure versions of curl, openssl, etc. The effect is that rasterio users on, say CentOS 5 or Ubuntu previous to 14.04, will have to compile their own rasterio 1.3.0 modules from source.
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