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Add a link to the temporary Haddocks

README.md

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 # HaskellGBM
 
-A Haskell wrapper around LightGBM.
+A Haskell wrapper around the [Microsoft LightGBM
+library](https://github.com/Microsoft/LightGBM) for machine learning
+uses.  The emphasis here is on using Haskell types to help ensure that
+the hyperparameter settings chosen by the user are coherent and
+in-bounds at all times.
+
+This software is not on Hackage yet - in the meantime you can find
+Haddock API documentation
+[here](https://dpkatz.github.io/haddocks/HaskellGBM-0.1.0.0/index.html)
+and a tutorial blog post
+[here](https://dpkatz.github.io/posts/using-lightgbm-from-haskell/).
+
+__N.B. This package is still under heavy development including API changes.__
 
-__N.B. This is pre-alpha software - the API and the implementation are both subject to change at a moment's notice.__
 
-You can find a tutorial on how to use it at https://dpkatz.github.io/posts/using-lightgbm-from-haskell/.