(lucene) branch main updated: Document scoring and ranking behavior across major versions (#15586)

[ja...@apache.org]

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jainankitk pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/lucene.git


The following commit(s) were added to refs/heads/main by this push:
     new eae18f231a7 Document scoring and ranking behavior across major versions (#15586)
eae18f231a7 is described below

commit eae18f231a7b2f54fc4bc2f191799f560c888466
Author: parveensaini <pa...@gmail.com>
AuthorDate: Fri Feb 6 16:49:49 2026 -0800

    Document scoring and ranking behavior across major versions (#15586)
---
 lucene/CHANGES.txt |  2 +-
 lucene/MIGRATE.md  | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt
index b242f8e94b1..755e3447a28 100644
--- a/lucene/CHANGES.txt
+++ b/lucene/CHANGES.txt
@@ -195,7 +195,7 @@ Bug Fixes
 
 Other
 ---------------------
-(No changes)
+* GITHUB#15586: Document that scoring and ranking may change across major Lucene versions, and that applications requiring stable ranking should explicitly configure Similarity. (Parveen Saini)
 
 ======================= Lucene 10.4.0 =======================
 
diff --git a/lucene/MIGRATE.md b/lucene/MIGRATE.md
index f567862a2f0..f0a838dbf9f 100644
--- a/lucene/MIGRATE.md
+++ b/lucene/MIGRATE.md
@@ -126,6 +126,17 @@ As part of GITHUB#13820, GITHUB#13825, GITHUB#13830, this issue corrects DataInp
 to be public and not-final, allowing subclasses to override it. This change also removes the protected
 DataInput.readGroupVInt method: subclasses should delegate or reimplement it entirely.
 
+### Scoring and ranking across major versions
+
+Lucene does not guarantee identical scoring or document ranking behavior across
+major version upgrades. Changes may occur due to improvements or modifications
+in Similarity implementations, query execution, or related internals.
+
+Applications that require stable ranking behavior across upgrades should
+explicitly configure the Similarity used for indexing and searching rather than
+relying on defaults. Reviewing `CHANGES.txt` for intervening major versions is
+recommended when upgrading.
+
 ### OpenNLP dependency upgrade
 
 [Apache OpenNLP](https://opennlp.apache.org) 2.x opens the door to accessing various models via the ONNX runtime. To migrate you will need to update any deprecated OpenNLP methods that you may be using.