Update README.md: Add note about Lucene 9 upgrade
@@ -14,6 +14,8 @@ Among other goals, our effort aims to be [the opposite of this](http://phdcomics
Anserini grew out of [a reproducibility study of various open-source retrieval engines in 2016](https://cs.uwaterloo.ca/~jimmylin/publications/Lin_etal_ECIR2016.pdf) (Lin et al., ECIR 2016).
See [Yang et al. (SIGIR 2017)](https://dl.acm.org/authorize?N47337) and [Yang et al. (JDIQ 2018)](https://dl.acm.org/citation.cfm?doid=3289400.3239571) for overviews.
+**NOTE**: Anserini was recently upgraded to Lucene 9.3 at commit [`272565`](https://github.com/castorini/anserini/commit/27256551e958f39495b04e89ef55de9d27f33414) (8/24/2022): this upgrade creates backward compatibility issues, see [#1952](https://github.com/castorini/anserini/issues/1952). Pyserini *has not* be similarly upgraded.
+
## Getting Started
Many Anserini features are exposed in the [Pyserini](http://pyserini.io/) Python interface.
@@ -283,6 +285,7 @@ Beyond that, there are always [open issues](https://github.com/castorini/anserin
## Historical Notes
++ Anserini was upgraded to Lucene 9.3 at commit [`272565`](https://github.com/castorini/anserini/commit/27256551e958f39495b04e89ef55de9d27f33414) (8/24/2022): this upgrade created backward compatibility issues, see [#1952](https://github.com/castorini/anserini/issues/1952).
+ Anserini was upgraded to Java 11 at commit [`17b702d`](https://github.com/castorini/anserini/commit/17b702d9c3c0971e04eb8386ab83bf2fb2630714) (7/11/2019) from Java 8.
Maven 3.3+ is also required.
+ Anserini was upgraded to Lucene 8.0 as of commit [`75e36f9`](https://github.com/castorini/anserini/commit/75e36f97f7037d1ceb20fa9c91582eac5e974131) (6/12/2019); prior to that, the toolkit uses Lucene 7.6.
