# Last week in scylla-cluster-tests.git master (issue #130; 2026-03-27)

**URL:** <https://forum.scylladb.com/t/last-week-in-scylla-cluster-tests-git-master-issue-130-2026-03-27/5330>\
**Category:** ScyllaDB\
**Tags:** git-testing-news\
**Created:** [March 27, 2026, 5:26pm UTC](https://forum.scylladb.com/t/last-week-in-scylla-cluster-tests-git-master-issue-130-2026-03-27/5330 "2026-03-27T17:26:40Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![soyacz](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.scylladb.com/soyacz/32/557_2.png) [@soyacz](https://forum.scylladb.com/u/soyacz)\
**Post date:** [March 27, 2026, 5:26pm UTC](https://forum.scylladb.com/t/last-week-in-scylla-cluster-tests-git-master-issue-130-2026-03-27/5330/1 "2026-03-27T17:26:40Z")

</div>

This short report brings to light some interesting commits to [scylla-cluster-tests.git master](https://github.com/scylladb/scylla-cluster-tests) from the last week. Commits in the 4f94cd24…47ed698f range are covered.

There were 67 non-merge commits from 15 authors in that period. Some notable commits:

The nemesis system received a substantial refactoring. The `disrupt_method_wrapper` was [removed entirely](https://github.com/scylladb/scylla-cluster-tests/commit/202f73fb4f00498eaf2360cb17db0e4c060c2af2), with all logic consolidated into `execute_nemesis` after a series of [extraction](https://github.com/scylladb/scylla-cluster-tests/commit/9913e6462d9f59a0a2c703e64d0c00ba58994b94), [simplification](https://github.com/scylladb/scylla-cluster-tests/commit/7dd1997df6574fe928924818cd6dcb7abf810dd2), and [target pool handling improvements](https://github.com/scylladb/scylla-cluster-tests/commit/80c0e55fb3c7d47b68541e7bdcaaa9a3542af89c). A new [nemesis hooks mechanism for ClusterTester](https://github.com/scylladb/scylla-cluster-tests/commit/fdb537036872af2b75de241daa888c84d2c6427e) enables running code before and after each nemesis without hardcoding it in nemesis code. Comprehensive [unit tests](https://github.com/scylladb/scylla-cluster-tests/commit/8e4e7139973a9070cc705f7f29cc31d2fed1a982) and a [nemesis developer guide](https://github.com/scylladb/scylla-cluster-tests/commit/3e49da192385b205e5d386282345bfb68e9229d8) with a [writing-nemesis skill](https://github.com/scylladb/scylla-cluster-tests/commit/16a42269a4dbec0fdcf7f2d55c970418565d1acc) were added alongside the rework.

Cluster health checks can now [run in parallel using a ThreadPoolExecutor](https://github.com/scylladb/scylla-cluster-tests/commit/37f959745460588e8f693958124f2eb81f46187d), with the number of workers configurable via the new `cluster_health_check_parallel_workers` parameter (default: 5).

Performance regression testing is being migrated to ARM64. New [i8g.4xlarge Jenkins jobs](https://github.com/scylladb/scylla-cluster-tests/commit/c01d80779ad8b6b987194a2e55566c0e37afa414) were created for both vnodes and tablets, consolidating all four subtests into a single job.

A new [error injection REST API client](https://github.com/scylladb/scylla-cluster-tests/commit/3a5803c0e73b0b1b51734cace6b965ac93ab28b9) adds support for enabling, disabling, and inspecting error injections on dev builds — useful for testing failure scenarios that require controlled fault injection.

Jenkins CI gained a [structured test failure summary](https://github.com/scylladb/scylla-cluster-tests/commit/eb1556df683d464cb324a892b58160ff2d782eee) that parses JUnit XML results and pre-commit logs, then posts a formatted comment on the PR.

Manager tests now support [configurable backup methods](https://github.com/scylladb/scylla-cluster-tests/commit/3e79e12c47e825830cabc0d4b17d01e56874a3e2), and the majority of jobs on Scylla 2025.3+ were [switched to native backup](https://github.com/scylladb/scylla-cluster-tests/commit/84a6f1c1526e9bd7d782e76ca1180f68d54d3771) instead of rclone.

The Argus client was [updated to 0.15.13](https://github.com/scylladb/scylla-cluster-tests/commit/fa9df676b8863bb44a23172bcc1e0a20f952400b), adding stress command timestamp support and POST retries.

The 5000-tables-latte scale tests were [promoted from tier2 to tier1](https://github.com/scylladb/scylla-cluster-tests/commit/47ed698f97756786955b69d70dc191f701092411) for both tablets and vnodes pipelines.

See you in the next issue of last week in scylla-cluster-tests.git master!