Senior Controls Software Engineer - CODESYS / TwinCAT

GCS Recruitment; Redmond (WA); Hybrid; USD 120,000 - 150,000; Full time

Job summary

GCS Recruitment is seeking a Senior Controls Software Engineer in Redmond, WA for a Hybrid role focused on industrial automation and material-handling systems. You will develop scalable control software using CODESYS V3 or Beckhoff TwinCAT, IEC 61131-3 Structured Text, and CASE-based state machines, with hardware integration and Git-based collaboration.

Bachelor-level engineering degree and 5+ years of relevant experience are required; strong debugging, testing on real hardware, and block-based

Qualifications

• Bachelor's degree in engineering, computer science, mechatronics, or related field.
• 5+ years of industrial automation or controls software experience.
• Hands-on CODESYS V3 or Beckhoff TwinCAT experience.
• Strong IEC 61131-3 Structured Text skills.
• Experience with state-machine architecture and CASE statements.
• Experience developing reusable Function Blocks.
• Understanding of PLC object-oriented programming.
• Experience with EtherCAT and industrial hardware.
• Experience with Git and software development practices.

Responsibilities

• Develop machine-control software using CODESYS V3 or Beckhoff TwinCAT.
• Program reusable Function Blocks and libraries using Structured Text.
• Develop CASE-based state machines for machine sequencing and equipment control.
• Apply object-oriented programming principles to PLC software.
• Integrate motors, drives, sensors, actuators, and other automation devices.
• Configure and troubleshoot EtherCAT networks.
• Develop fault detection, recovery, startup, shutdown, and equipment-state logic.
• Test and debug control applications using real industrial hardware.
• Read electrical schematics and control drawings.
• Support application deployment and commissioning.
• Participate in Git-based development and code reviews.

Skills

CODESYS V3

Beckhoff TwinCAT

IEC 61131-3 Structured Text

State-machine architecture

CASE statements

Reusable Function Blocks

Git version control

Education

Bachelor's degree in Engineering, Computer Science, Mechatronics, or related field

Tools

EtherCAT

Git

JSON configuration

Linux-based Industrial PCs

IO-Link exposure

Job description

Senior Controls Software Engineer - CODESYS / TwinCAT

Location: Redmond, WA
Work Model: Hybrid
Experience: 5+ Years

Job Overview

We are seeking a Senior Controls Software Engineer to develop scalable software for advanced industrial automation and material-handling systems.

The ideal candidate will have strong hands-on experience with CODESYS V3 or Beckhoff TwinCAT, IEC 61131-3 Structured Text, state-machine programming, and industrial hardware integration.

Key Responsibilities

• Develop machine-control software using CODESYS V3 or Beckhoff TwinCAT.
• Program reusable Function Blocks and libraries using Structured Text.
• Develop CASE-based state machines for machine sequencing and equipment control.
• Apply object-oriented programming principles to PLC software.
• Integrate motors, drives, sensors, actuators, photo-eyes, and other automation devices.
• Configure and troubleshoot EtherCAT networks.
• Develop fault detection, recovery, startup, shutdown, and equipment-state logic.
• Test and debug control applications using real industrial hardware.
• Read electrical schematics and control drawings.
• Support application deployment and commissioning.
• Participate in Git-based development and code reviews.

Required Qualifications

• Bachelor's degree in Engineering, Computer Science, Mechatronics, or related field.
• 5+ years of industrial automation or controls software experience.
• Hands-on CODESYS V3 or Beckhoff TwinCAT experience.
• Strong IEC 61131-3 Structured Text skills.
• Experience with state-machine architecture and CASE statements.
• Experience developing reusable Function Blocks.
• Understanding of PLC object-oriented programming.
• Experience with EtherCAT and industrial hardware.
• Experience with Git and software development practices.

Preferred

• Conveyor or material-handling experience.
• Warehouse or packaging automation.
• IO-Link experience.
• Linux-based Industrial PCs.
• JSON configuration.
• Experience with commissioning and deployment.
• C++ or Rust exposure.