
Aliaksandr Fedasiuk engineered robust backend solutions and test automation for the Folio platform, focusing on data import reliability, multi-tenant workflows, and secure deployment practices. In repositories like mod-source-record-manager and folio-integration-tests, he delivered features such as snapshot management for source storage records, event-driven job deduplication, and multi-tenant test environments. His work leveraged Java, Spring Boot, and Karate DSL, emphasizing asynchronous processing, error handling, and configuration management. By refactoring event flows, optimizing SQL queries, and standardizing environment-driven settings, Aliaksandr improved system resilience, observability, and CI stability, demonstrating depth in backend development and cross-repository coordination for complex library workflows.

Summary for 2025-10: Achieved multi-tenant testing capabilities and stabilized critical test suites across folio-integration-tests and mod-source-record-storage. Key features delivered include a unified Test Environment Configuration enabling consortium tenant testing and a temporary test cluster (folio-tmp-test), including switching the default test tenant to consortium and adding credentials. Enhanced Consortia Inventory Testing to cover new endpoints, add member-tenant location management, and introduce a cross-tenant ownership transfer scenario, with adjustments for pre-existing data and API delays. Stabilized the DataImportLargeScaleTest in Karate by refining test data and execution flow. These improvements increase CI reliability, reduce flaky tests, and accelerate validation of multi-tenant workflows, delivering business value through faster, safer deployments and higher confidence in consortium integrations.
Summary for 2025-10: Achieved multi-tenant testing capabilities and stabilized critical test suites across folio-integration-tests and mod-source-record-storage. Key features delivered include a unified Test Environment Configuration enabling consortium tenant testing and a temporary test cluster (folio-tmp-test), including switching the default test tenant to consortium and adding credentials. Enhanced Consortia Inventory Testing to cover new endpoints, add member-tenant location management, and introduce a cross-tenant ownership transfer scenario, with adjustments for pre-existing data and API delays. Stabilized the DataImportLargeScaleTest in Karate by refining test data and execution flow. These improvements increase CI reliability, reduce flaky tests, and accelerate validation of multi-tenant workflows, delivering business value through faster, safer deployments and higher confidence in consortium integrations.
September 2025 monthly summary focusing on key accomplishments, features delivered, major fixes, and impact across folio-org repositories. Highlights include cross-instance holdings/items movement reliability, event-processing correctness via a cancellation cache, and deadlock mitigation in journal record insertions. These changes improve data integrity, reliability, and throughput in inventory, invoicing, and source-record management, while showcasing skills in logging, event-driven architectures, caching, and concurrency control.
September 2025 monthly summary focusing on key accomplishments, features delivered, major fixes, and impact across folio-org repositories. Highlights include cross-instance holdings/items movement reliability, event-processing correctness via a cancellation cache, and deadlock mitigation in journal record insertions. These changes improve data integrity, reliability, and throughput in inventory, invoicing, and source-record management, while showcasing skills in logging, event-driven architectures, caching, and concurrency control.
August 2025 monthly summary for folio-org/mod-inventory: - Delivered SnapshotService to manage snapshots for Source Storage Records (SRS) and Ownership Transfer, centralizing creation and lifecycle handling. - Refactored UpdateOwnershipApi and related event handlers to post snapshots via the new service, improving consistency, error handling, and testability across the ownership transfer workflow. - Resolved a MARC holdings accessibility issue exposed after Ownership updates (quickMARC), tied to the changes in the snapshot flow.
August 2025 monthly summary for folio-org/mod-inventory: - Delivered SnapshotService to manage snapshots for Source Storage Records (SRS) and Ownership Transfer, centralizing creation and lifecycle handling. - Refactored UpdateOwnershipApi and related event handlers to post snapshots via the new service, improving consistency, error handling, and testability across the ownership transfer workflow. - Resolved a MARC holdings accessibility issue exposed after Ownership updates (quickMARC), tied to the changes in the snapshot flow.
July 2025 monthly summary for folio-org/folio-integration-tests: Delivered robust test coverage for data import workflows and stabilized authentication and job verification. Key features include Karate-based tests for electronic records with additional holdings/items and long-running DI jobs, aligned to SRS MARC profiles. Major fixes addressed unauthorized errors during long executions via improved token handling and extended pause durations, with clearer separation of success/failure job verification. Overall, the work resulted in a more reliable integration test suite, reduced flaky CI runs, and faster feedback for MARC/import feature changes. Demonstrated capabilities in test automation, profile-driven data import, and resilient authentication flows, driving business value through safer releases and higher confidence in production readiness.
July 2025 monthly summary for folio-org/folio-integration-tests: Delivered robust test coverage for data import workflows and stabilized authentication and job verification. Key features include Karate-based tests for electronic records with additional holdings/items and long-running DI jobs, aligned to SRS MARC profiles. Major fixes addressed unauthorized errors during long executions via improved token handling and extended pause durations, with clearer separation of success/failure job verification. Overall, the work resulted in a more reliable integration test suite, reduced flaky CI runs, and faster feedback for MARC/import feature changes. Demonstrated capabilities in test automation, profile-driven data import, and resilient authentication flows, driving business value through safer releases and higher confidence in production readiness.
May 2025 focused on security, reliability, and deployment consistency across Folio modules. Delivered dependency upgrades, TLS/SSL hardening, and MARC processing improvements for storage; standardized environment-variable based configuration (SYSTEM_USER_ENABLED) across multiple modules; updated build tooling to align with latest security patches; and strengthened testing to reduce deployment risk.
May 2025 focused on security, reliability, and deployment consistency across Folio modules. Delivered dependency upgrades, TLS/SSL hardening, and MARC processing improvements for storage; standardized environment-variable based configuration (SYSTEM_USER_ENABLED) across multiple modules; updated build tooling to align with latest security patches; and strengthened testing to reduce deployment risk.
April 2025 Monthly Summary: Reliability, Observability, and Dependency Alignment Key features delivered - mod-source-record-storage: Dependency upgrade to data-import-processing-core 4.5.0-SNAPSHOT (no functional changes) to align with the processing core. Major bugs fixed - mod-source-record-manager: Prevented duplicate DI completion events and stabilized composite job completion updates by centralizing and deduplicating event emission and refining updateBlocking in JobExecutionDaoImpl; enhanced logging for traceability. Commits: 6eb8b88de8d55b94e3fe6be77398107008571a5d, ffd16f51e3bbbe06433e528961be952641bfcf34. - data-import-processing-core: Fixed MARC bibliographic records update crash (NullPointerException) by refactoring EventManager and MarcRecordModifier to use safe list accessors (getFirst/getLast) and enhanced logging and protection matching logic. Commit: 3d32588fea16bdcd36f4af56f5bfd15705677a36. Overall impact and accomplishments - Significantly reduced risk of duplicate DI events and unstable composite job updates, improving data consistency and processing reliability. - Eliminated a critical NullPointerException during MARC records updates, increasing robustness of bibliographic data processing. - Improved observability with enhanced logging to enable easier tracing and debugging in production. - Prepared systems for future changes by aligning downstream modules with the latest data-import-processing-core version. Technologies/skills demonstrated - Java, refactoring, defensive programming, event-driven design, enhanced logging, dependency management, change coordination across multiple repositories.
April 2025 Monthly Summary: Reliability, Observability, and Dependency Alignment Key features delivered - mod-source-record-storage: Dependency upgrade to data-import-processing-core 4.5.0-SNAPSHOT (no functional changes) to align with the processing core. Major bugs fixed - mod-source-record-manager: Prevented duplicate DI completion events and stabilized composite job completion updates by centralizing and deduplicating event emission and refining updateBlocking in JobExecutionDaoImpl; enhanced logging for traceability. Commits: 6eb8b88de8d55b94e3fe6be77398107008571a5d, ffd16f51e3bbbe06433e528961be952641bfcf34. - data-import-processing-core: Fixed MARC bibliographic records update crash (NullPointerException) by refactoring EventManager and MarcRecordModifier to use safe list accessors (getFirst/getLast) and enhanced logging and protection matching logic. Commit: 3d32588fea16bdcd36f4af56f5bfd15705677a36. Overall impact and accomplishments - Significantly reduced risk of duplicate DI events and unstable composite job updates, improving data consistency and processing reliability. - Eliminated a critical NullPointerException during MARC records updates, increasing robustness of bibliographic data processing. - Improved observability with enhanced logging to enable easier tracing and debugging in production. - Prepared systems for future changes by aligning downstream modules with the latest data-import-processing-core version. Technologies/skills demonstrated - Java, refactoring, defensive programming, event-driven design, enhanced logging, dependency management, change coordination across multiple repositories.
March 2025 monthly summary focusing on delivering robust data import and reliable DI event processing across core Folio modules. Key emphasis on business value through improved data integrity, system reliability, and scalable event-driven workflows.
March 2025 monthly summary focusing on delivering robust data import and reliable DI event processing across core Folio modules. Key emphasis on business value through improved data integrity, system reliability, and scalable event-driven workflows.
February 2025 monthly summary: Delivered reliability and performance improvements across two Folio modules. Implemented a safe, configurable cleanup for MARC indexer versions to prevent 'No space left on device' errors, with per-call processing limits and enhanced scheduling for periodic/time-based deletions. Also optimized discovery data retrieval in mod-inventory-storage by updating the query to leverage an index on the discoverySuppress field, reducing retrieval time and load.
February 2025 monthly summary: Delivered reliability and performance improvements across two Folio modules. Implemented a safe, configurable cleanup for MARC indexer versions to prevent 'No space left on device' errors, with per-call processing limits and enhanced scheduling for periodic/time-based deletions. Also optimized discovery data retrieval in mod-inventory-storage by updating the query to leverage an index on the discoverySuppress field, reducing retrieval time and load.
December 2024 monthly summary for the Folio project focused on stabilizing batch save workflows for Bib records linked to Authority, improving data integrity and resilience in the mod-source-record-storage module.
December 2024 monthly summary for the Folio project focused on stabilizing batch save workflows for Bib records linked to Authority, improving data integrity and resilience in the mod-source-record-storage module.
Month: 2024-11. Delivered a critical reliability fix for MARC data import in the mod-source-record-manager. Resolved empty SRS MARC and Authority tabs during MARC authority log data import by properly handling the update event DI_MARC_FOR_UPDATE_RECEIVED and by refining logging and data processing paths across StoredRecordChunksKafkaHandler and JournalParams. Updated NEWS.md to document the fix and linked to MODSOURMAN-1249 for traceability. The change is captured under commit c597b4fa835ec17c3d1959360fa197712ea29da4 (MODSOURMAN-1249).
Month: 2024-11. Delivered a critical reliability fix for MARC data import in the mod-source-record-manager. Resolved empty SRS MARC and Authority tabs during MARC authority log data import by properly handling the update event DI_MARC_FOR_UPDATE_RECEIVED and by refining logging and data processing paths across StoredRecordChunksKafkaHandler and JournalParams. Updated NEWS.md to document the fix and linked to MODSOURMAN-1249 for traceability. The change is captured under commit c597b4fa835ec17c3d1959360fa197712ea29da4 (MODSOURMAN-1249).
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