Mainframe Python

Position: Senior Python Engineer — Mainframe (DB2/JCL)
Location: Atlanta, GA (Onsite)


Senior Python Engineer — Mainframe (DB2/JCL) Design & build Python on z/OS (USS): Develop CLI tools, services, and batch utilities that run natively on z/OS Unix System Services (USS) or orchestrate mainframe
jobs from distributed hosts. Batch orchestration: Create and maintain JCL (PROCs, symbolics, condition codes, GDGs) and integrate with enterprise schedulers (e.g., Control-M, CA-7). Implement robust restart/recovery and step-level error handling. DB2 for z/OS engineering: Write and tune SQL; implement stored procedures; design schemas and indexes; use EXPLAIN, RUNSTATS, and utilities
(LOAD/UNLOAD/REORG) to hit SLAs. Python–DB2 integration: Connect via ibm_db/CLI/ODBC and optimize connection pooling, cursor usage, and transaction boundaries for high-throughput workloads. Data processing pipelines (plus): Build high-volume ETL/ELT flows with Python (e.g.,
pandas, PyArrow, Dask) and efficient I/O (binary formats, streaming, chunking). Job submission & automation: Submit and monitor jobs via SDSF, z/OSMF REST APIs, or Zowe CLI; parse JES output; automate handoffs and notifications. Reliability & observability: Implement structured logging, metrics, and tracing; integrate with enterprise monitoring (e.g., Splunk, ELK). Testing & CI/CD: Enforce unit/integration tests (pytest), code reviews, linting/type hints (flake8/ruff/mypy), packaging, and CI/CD (e.g., Jenkins, GitLab).
Security & compliance: Follow RACF/Top Secret/ACF2 controls, least privilege, and data governance for PII/PCI/SOX environments.
Mentorship & documentation: Coach engineers on Python + mainframe best practices; produce clear runbooks and architecture docs.

Required qualifications 8+ years professional Python (3.x) building reliable, performant production systems (CLIs, services, or batch).

Hands-on Python on the mainframe (must-have): Comfortable with z/OS USS, TSO/ISPF, SDSF, OMVS, dataset concepts (PS/PO, GDGs), code pages/EBCDIC vs ASCII, and file I/O nuances.

Mainframe DB2 expertise: Strong DB2 for z/OS (SQL tuning, indexing strategies, access paths,
utilities, locking & concurrency). Familiar with SPUFI, DSNTEP2, IBM Data Studio (or equivalents). Deep JCL proficiency: PROCs, symbolic parms, condition codes, dataset allocation, DFSORT/ICETOOL, IDCAMS, and common utilities; experience wiring JCL into enterprise schedulers. Scripting & OS: Shell (sh/bash) on USS; comfort with dataset/file conversions, large file throughput, and job logs. SDLC
discipline: Git, trunk-based development, code reviews, tickets/change management (e.g., Jira/ServiceNow).

Excellent communicator with the ability to translate between mainframe, data, and app teams.
Nice-to-have (strong plus) Data-processing Python: pandas, PyArrow, Dask; memory/perf tuning for large datasets; binary formats (Parquet/Avro).

Automation toolchain: Zowe CLI, z/OSMF REST, IBM Z Open Automation Utilities, Ansible for z/OS. Integration: IBM MQ, CICS, Kafka/CDC (e.g., IBM Data Replication), REST/gRPC services bridging z/OS and distributed. Performance engineering: SMF insights, buffer pool tuning (with DBAs), batch window optimization.

Refactoring legacy: Translating COBOL/PL/I batch logic to Python where appropriate; creating safe migration paths. Distributed data engines:
PySpark/Spark (for off-platform processing), Airflow. Observability & SRE: SLA/SLO design, incident response for nightly/weekly batch cycles.

Tools & environment (illustrative) Mainframe: IBM z/OS 2.x, USS, TSO/ISPF, SDSF, RACF/Top Secret/ACF2 Data: DB2 12/13 for z/OS; utilities (REORG/RUNSTATS/LOAD/UNLOAD) Python: 3.x, venv/poetry, ibm_db/ODBC, requests, pandas/PyArrow (as applicable) Automation: Zowe
CLI, z/OSMF APIs, Control-M/CA-7, Jenkins/GitLab CI Monitoring: Splunk/ELK, enterprise log aggregation Success metrics Batch SLAs consistently met; reduced average job elapsed time and rerun rates Measurable DB2 query/perf improvements (e.g., CPU, getpages, elapsed time) Increased automation coverage (job submission/monitoring, recovery) High test coverage and low change-failure rate across releases Education & certification BS/MS in CS, EE, or equivalent experience

Nice-to-have: IBM Certified Database Admin — DB2 for z/OS; IBM z/OS Associate/Professional; Control-M/CA-7 certifications