Mainframe Developer - COBOL/Natural/Adabas

Innosoft Corporation; New York (NY); Remote; USD 90,000 - 130,000; Part time

Benefits offered by this job

Health insurance

Paid vacation

401K match

STD/LTD/AD&D

Job summary

Innosoft Corporation seeks an experienced Enterprise COBOL developer for a 6-month remote contract to extend a z/OS mainframe accounting platform. You will read a large COBOL body, implement a pooled-account structure, and ensure postings, balances, and reconciliations are exact.

Responsibilities include modifying COBOL/JCL, extending batch cycles, adding audit trails, producing test data, and supporting conversion and early-life production runs with strong documentation and communication.

Qualifications

• Education: Degree in computer science or related field, or equivalent practical experience.
• Required Skills: 5+ years of Enterprise COBOL development experience in a z/OS environment
• 5+ years of experience with NaturalOne
• 3+ years of JCL development and production support experience
• 3+ years of experience with financial/accounting systems development or support including double-entry posting, balance/accrual maintenance, value dating, reconciliation, and month-end closeouts in a regulated environment
• 3+ years with Adabas and VSAM
• 3+ years tracing undocumented logic through copybooks, call chains, and job streams
• Preferred Skills: Experience with cash management, account pooling, sweeps, or treasury applications
• Experience with CA-7 scheduling and batch operations
• Experience with REXX, Python, or Java
• Mixed-estate integration — COBOL and Natural, z/OS Connect, IBM MQ, or REST services
• Scheduling and operations — CA-7 batch window analysis and performance tuning
• Scripting and adjacent languages — REXX or CLIST, plus Java or Python for data migration
• Cash management domain — pooling, sweeps, intercompany allocation
• Additional Skills: Track record of taking a spec from analysis through production with limited supervision
• Clear written communication: explain changes to auditors, business analysts, and developers

Responsibilities

• Analyze the current account master, posting, and balance-maintenance programs to establish recognition points for composite reservoir accounts and document findings.
• Design and code the new account type end to end: master file and table structures, account opening/closing, participant linkage, sweep logic, allocation, and closing balance derivation.
• Modify batch COBOL programs and JCL and extend nightly and month-end cycles to include new processing without lengthening batch windows.
• Add new CRAs to the audit trail, exception reporting, and reconciliation controls; collaborate with accounting stakeholders.
• Produce test data, unit and regression test packs, and parallel-run comparisons against current production output; investigate differences.
• Support implementation, conversion of in-scope accounts, and early-life production runs, including on-call during first cycles.
• Leave behind program documentation, data-flow notes, and runbook updates for the support team.

Skills

Enterprise COBOL

z/OS

NaturalOne

JCL

Adabas

VSAM

REXX

Python

Java

Batch scheduling

CA-7 scheduling

REST services

Education

CS degree or equivalent

Tools

CA-7

z/OS Connect

IBM MQ

REST API

Job description

Project Identifier

SC

Client

South Carolina

Agency

State of South Carolina

Location

Remote (Role is 100% remote; 8:00 AM to 5:00 PM)

1200 Senate St, Columbia, South Carolina, USA, 29201.

No SC residency required. Candidate must reside in lower 48 states (Continental US) and comfortable working EST time zone hours.

Contract Duration

6 Months

Interview Type

1-2 rounds of Virtual Interviews

The candidate will have to be on an Innosoft W2.

At least 6 months of valid work authorization

Tentative Start Date

12/01/2026

Deadline

11/04 05 /2026

Project Overview

Build a new pooled-account structure inside a running z/OS core, without disturbing the balances already on it.

We are adding new composite reservoir accounts to our existing mainframe accounting platform: a pooled account structure in which balances from multiple subsidiary accounts are concentrated into, and drawn back from, a single reservoir account under defined sweep and allocation rules.

This is additional function inside a legacy system. You will be reading a large body of COBOL that has been in production for an extended period, much of it lightly documented, and extending it so that the new account type posts, settles, accrues, reports, and reconciles exactly as the existing types do. Correctness and traceability of every cent matter more than speed of delivery.

Production changes follow formal change control with peer review and a signed-off implementation plan.

Duties/Responsibilities:

• Analyze the current account master, posting, and balance-maintenance programs to establish where composite reservoir accounts must be recognized, and document what you find.
• Design and code the new account type end to end: master file and table structures, account opening and closing, participant linkage, sweep and reverse-sweep logic, allocation and interest apportionment, and closing balance derivation.
• Modify batch COBOL programs and JCL and extend the nightly and month-end cycles to include the new processing without lengthening the batch window beyond agreed limits.
• Add new CRAs to the audit trail, exception reporting, and reconciliation controls the new function requires, working with accounting stakeholders on what must be evidenced.
• Produce test data, unit and regression test packs, and parallel-run comparisons against current production output; investigate every difference until it is explained.
• Support implementation, conversion of any in-scope existing accounts, and early-life production runs, including on-call cover during the first cycles.
• Leave behind program documentation, data-flow notes, and runbook updates that the support team can work from.

Requirements

• Education and Certifications: Degree in computer science or a related field, or equivalent practical experience.
• Required Skills: 5+ years of Enterprise COBOL development experience in a z/OS environment
• 5+ years of experience with NaturalOne
• 3+ years of JCL development and production support experience
• 3+ years of experience with financial/accounting systems development or support including double-entry posting, balance/accrual maintenance, value dating, reconciliation, and month-end closeouts in a regulated environment
• 3+ years of experience working with Adabas and VSAM
• 3+ years of experience with tracing undocumented logic through copybooks, call chains, and job streams
• Preferred Skills: Experience with cash management, account pooling, sweeps, or treasury applications
• Experience with CA-7 scheduling and batch operations
• Experience with REXX, Python, or Java
• Mixed-estate integration — calling between COBOL and Natural, and exposing mainframe function through z/OS Connect, IBM MQ, or REST services.
• Scheduling and operations — CA-7 batch window analysis and performance tuning.
• Scripting and adjacent languages — REXX or CLIST for tooling, plus Java or Python for data comparison and migration work.
• Cash management domain — notional and physical pooling, cash concentration, sweeps, and intercompany allocation.
• Additional Skills: Track record of taking a specification from analysis through production implementation with limited supervision.
• Clear written communication: you can explain a change to an auditor, a business analyst, and another developer, and adjust the explanation for each.

Standard Employee Benefits.

• 50% Health Insurance Paid by Innosoft, Paid Vacation, 401K Match, STD LTD and AD&D paid by Innosoft.