Staff Software Engineer, Quality Integration ANDURIL INDUSTRIESStaff Software Engineer, Quality IntegrationBoston, MA$166,000–$220,000 / yearThis role is open to senior technical leaders ready to own the architecture of how Software Platform ships - the Integrated Continuous Release (ICR) pipeline, full automation of local and integrated end-to-end test environments, and enforcement of contract-verification models that every Lattice service will ship against. Drive the continuous integration of performance testing into CI/CD pipelines, establishing and enforcing performance baselines and championing reliability engineering best practices to proactively identify and prevent regressions across the entire software stack.
Scientific Software Engineer - AMO Simulations QuEra Computing IncScientific Software Engineer - AMO SimulationsBoston, MABuild production-grade software infrastructure and tools to efficiently model Rydberg interactions, atom motion, atom loss, laser control imperfections, decoherence channels, and other device-relevant effects, supporting AMO theory and device modeling efforts. You will build simulation and analysis tools that help researchers understand system behavior, model noise and decoherence, validate control protocols, and connect device-level physics to higher-level quantum computing workflows.
Quantum Optics Communication Engineer-Technical Staff MIT Lincoln LaboratoryQuantum Optics Communication Engineer-Technical StaffLexington, MA$145,200–$170,000 / yearExamples of near-term field tests include terabit-per-second direct-to-Earth small-satellite constellations, near-Earth wideband relay laser communication terminal hardware for space and ground terminal use, and next-generation beam-director prototypes that are inherently scalable to deep-space optical comm systems, and quantum state transfer across a regional quantum network testbed. Primary areas of research include the development of novel entangled-photon source technologies and quantum memory systems; novel quantum link architectures; sensitive single-photon receivers; novel modulation and coding approaches; multi-format laser-comm modems; robust and compact free-space optical beam directors; and precision beam pointing, link acquisition and tracking systems.
Manufacturing Test Engineer II The Kemtah Group, Inc.Manufacturing Test Engineer IINHLocation: Hudson, NH Zip Code: 03051 Job Type: Contract Job Duration: 3 Months Schedule and Shift: 9-80 A|1st Shift|08:30 AM|N Keyword''s: #Hudsonjobs; #Manufacturingjibs; #TestEngineerjobs; Start Date: Immediate We provide a competitive pay and benefits package. This highly technical role calls for a seasoned engineer with deep expertise in hardware-level diagnostics, as well as the vision to drive process improvement and test strategy innovation across teams.
Software Engineer, Design Automation (Senior / Staff+) Reframe SystemsSoftware Engineer, Design Automation (Senior / Staff+)Boston, MassachusettsWe're looking for a Staff Software Engineer to own the hardest parts of our design automation platform: the system that takes a high-level design and, with minimal intervention, produces a manufacturable model and production plan (think: every stud, nail, HVAC register, and duct placed). Through our vertically integrated delivery model and highly automated microfactories, we deliver climate resilient homes and buildings with greater speed and predictability than traditional construction.
System Mechanical & Integration Engineer Analog Devices IncSystem Mechanical & Integration EngineerWilmington, MA$110,385–$151,808 / yearADI combines analog, digital, AI, and software technologies into solutions that combat climate change, reliably connect humans and the world, and help drive advancements in automation and robotics, mobility, healthcare, energy and data centers. In this role, you will work alongside experienced power electronics, thermal, mechanical, systems, and reliability engineers to design, integrate, and validate high-density power supply systems for AI and cloud computing infrastructure.
Senior Industrial Engineer ANDURIL INDUSTRIESSenior Industrial EngineerWaltham, MA$146,000–$194,000 / yearOwn the reporting and analysis of manufacturing health and ensure that stakeholders have the inputs they need to make decisions across Engineering (cut-in dates for new designs), Supply Chain (signals on what to buy), Manufacturing (signals on being clear-to-build and what to build), and Growth (supply overview to drive customer contracts). Our team is responsible for rapidly iterating and building cutting-edge defense hardware, including static equipment, ground vehicles, sensors, undersea systems, and flight vehicles, while scaling these products across existing and new manufacturing facilities.
Principal Engineer, Power Systems Engineering Analog Devices IncPrincipal Engineer, Power Systems EngineeringWilmington, MA$157,080–$227,460 / yearThis Principal Engineer, Power Systems Engineering position is a fast-paced role involving using ADI's portfolio of high-performance power products to solve engineering challenges in the industry by developing system-level solutions and references for a wide variety of applications. ADI combines analog, digital, AI, and software technologies into solutions that combat climate change, reliably connect humans and the world, and help drive advancements in automation and robotics, mobility, healthcare, energy and data centers.
Laser Systems Engineer QuEra Computing IncLaser Systems EngineerBoston, MA$128,000–$208,000 / yearDesign and develop infrastructure-grade laser systems built for repeatability, modularity, and field serviceability - programmable optical engines with calibration-friendly architectures, integrated modulators, co-packaging approaches, and well-defined interfaces compatible with automated control and monitoring infrastructure. Contribute to shaping how laser management scales with fleet growth - reducing per-system overhead through novel automation approaches including AI-powered control agents and LLM-assisted workflows for complex tasks such as autonomous laser locking and heterogeneous hardware orchestration.
Hardware Technician Diverse Lynx, LLCHardware TechnicianLynnwood, MAStrong experience with system integration, networking, operating system / software installation and maintenance, help desk, and/or data storage technology, specifically with Windows, Linux & VMware systems. Under general supervision, performs intermediate engineering assignments associated with the receiving, staging and initial configuration of computer equipment to meeting design specifications.
NewHardware Development Manager, Amazon Industrial Robotics Amazon.com IncHardware Development Manager, Amazon Industrial RoboticsNorth Reading, MAAmazon is seeking exceptional talent to help develop the next generation of advanced robotics systems that will transform automation at Amazon"s scale. As a Hardware Development Manager, you will be responsible for developing complex computing and firmware systems that power our robotic platforms.
NewSenior Electrical Engineer - Digital Design RTX CorpSenior Electrical Engineer - Digital DesignTewksbury, MARaytheon's Hardware Electrical Engineering team designs, validates, qualifies, and supports production of digital electronic circuit cards and electronic units used in demanding aerospace and defense applications. As part of our commitment to maintaining a secure hiring process, candidates may be asked to attend select steps of the interview process in-person at one of our office locations, regardless of whether the role is designated as on-site, hybrid or remote.
Digital Design Engineer Judit IncDigital Design EngineerLexington, MAStrong verbal and written communications skills including collaborating with other on-site and/or remote technical team members, preparing and sharing technical results with others, and documenting work to aid other team members and activities. Experience designing and testing programmable logic designs targeting System on Chip (SoC) FPGA architectures that required integration of the programmable logic with on-chip software processing.
Senior Embedded Software Engineer Webster & Webster AssociatesSenior Embedded Software EngineerBoston, MassachusettsThis role is ideal for a highly skilled software engineer with a strong background in C programming, networking, and security, looking to develop high-performance cryptographic algorithms and security protocols for embedded systems. Working knowledge of various operating environments, including Linux, Windows, Embedded Linux, and RTOS (e.g., VxWorks, QNX, ThreadX, FreeRTOS, uC/OS, MQX).
R&D Software Engineer (FT) DelsysR&D Software Engineer (FT)Natick, MassachusettsSoftware Engineers in this role will focus on building robust backend systems, embedded processing pipelines, and real-time applications for physiological monitoring, human movement tracking, VR/AR experiences, speech analysis, and neural interface technologies. Successful candidates will collaborate closely with developers, R&D engineers and scientists, gaining hands-on experience in translating research innovations into deployable technologies.
PCB Design Engineer Murata Electronics North America, Inc.PCB Design EngineerWestborough, MA$101,000–$115,000 / yearKnown for the quality of our technology and the strength of our team, Murata Power Solutions offers the opportunity to work with talented engineers and a leadership group committed to growth, innovation, and partnership with many of the world's leading OEMs. Bachelor's degree in Electrical Engineering, Electronics, or related field with 3-5 years of PCB design experience; or Associate's degree with 5-7 years of experience.
Staff Software Engineer (Backend) Axiomatic AIStaff Software Engineer (Backend)Boston, MassachusettsBy combining deep learning with formal logic and physics-based modeling, we create verifiable, interpretable AI systems that collaborate with and support human researchers in high-stakes scientific and engineering workflows. This is a hands-on, T-shaped role with a deep backend specialization : you'll spend roughly 70% of your time writing and reviewing backend code , 20% on architecture and technical strategy , and 10% contributing to frontend work when needed.
DSP Engineer - Audio Tech Bose CorpDSP Engineer - Audio TechFramingham, MA$97,600–$134,200 / yearDSP engineers in the Audio Technology Licensing group work in cross-disciplinary, highly collaborative teams to develop and deploy signal processing algorithms that improve audio experiences for our technology partners and their customers. While Bose is well known for its first-party consumer and automotive products, an increasingly important part of our future is enabling partners around the world to deliver differentiated audio experiences through licensed Bose technologies.
Digital Signal Processing Engineer - Audio Technology Bose CorpDigital Signal Processing Engineer - Audio TechnologyFramingham, MA$138,100–$189,850 / yearDSP engineers in the Audio Technology Licensing group work in cross-disciplinary, highly collaborative teams to develop and deploy signal processing algorithms that improve audio experiences for our technology partners and their customers. The Audio Technology Licensing organization focuses on developing scalable, portable, and high-performance audio technologies that can be deployed across a wide range of partner platforms and products.
NewDigital Signal Processing Engineer – Audio Technology Bose Corporation, U.S.ADigital Signal Processing Engineer – Audio TechnologyFramingham, Massachusetts$138,100–$189,850 / yearDSP engineers in the Audio Technology Licensing group work in cross-disciplinary, highly collaborative teams to develop and deploy signal processing algorithms that improve audio experiences for our technology partners and their customers. The Audio Technology Licensing organization focuses on developing scalable, portable, and high-performance audio technologies that can be deployed across a wide range of partner platforms and products.
Network Engineer Centuria CorporationNetwork EngineerMAAs one part of the greater Air Force Information Network (AFIN) enterprise, the 66 ABG Communications and Information Division (66 ABG/SC) has responsibilities in two categories (1) direct actions in support of Hanscom Air Force Base (HAFB) and geographically separated units (GSUs); and (2) indirect actions to support the AFIN enterprise. Be disciplined in approach to operational excellence and execute detailed record keeping for adherence to locally established and required military processes and procedures services which ensure that networks are compliant with applicable directives, publications, and/or guidelines as governed by external DoD agencies.
Embedded Hardware and Firmware Engineer Analog DevicesEmbedded Hardware and Firmware EngineerWilmington, MassachusettsFor positions requiring access to technical data, Analog Devices, Inc. may have to obtain export licensing approval from the U.S. Department of Commerce - Bureau of Industry and Security and/or the U.S. Department of State - Directorate of Defense Trade Controls. ADI combines analog, digital, AI, and software technologies into solutions that combat climate change, reliably connect humans and the world, and help drive advancements in automation and robotics, mobility, healthcare, energy and data centers.
Electrical Engineer Merlin LabsElectrical EngineerBoston, MAProvide guidance to other electrical engineers and technicians across the team working on electrical and electronic aspects of the system architecture and schematics including power, computer, electro-mechanical, interconnect systems, wireless communications, cable harnesses, packaging, cable routing, and user interfaces and controls. If you require reasonable accommodation in completing an application, interviewing, completing any pre-employment testing, or otherwise participating in the employee selection process, please direct your inquiries to: people@merlinlabs.com
RF Engineer - 20821-1 The Kemtah Group, Inc.RF Engineer - 20821-1Chelmsford, MAStart Date: Immediate Keyword''s: #chelmsfordjobs; #rfengineerjobs Must have an active a DoD Secret Clearance Our client is a global security and aerospace company that employs approximately 114,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration, and sustainment of advanced technology systems, products, and services. Expertise with RF subsystem and hardware including antennas, transmitters, receivers, microwave components, low noise amplifiers, high power amplifiers, advanced electronic modules, amplifiers, mixers, switches, frequency generation circuits and/or frequency conversion circuits is desired.
Senior Engineer, Design Evaluation Engineering Analog DevicesSenior Engineer, Design Evaluation EngineeringWilmington, MassachusettsRequirements: Must have a Master’s degree in Electrical Engineering or relevant technical discipline (willing to accept foreign education equivalent) and 12 months of experience as a Design Evaluation Engineer or related occupation automating various tests with lab test equipment including Network Analyzers, Spectrum Analyzers, Signal Generators and temperature chambers. For positions requiring access to technical data, Analog Devices, Inc. may have to obtain export licensing approval from the U.S. Department of Commerce - Bureau of Industry and Security and/or the U.S. Department of State - Directorate of Defense Trade Controls.
NewSenior Manufacturing Software Engineer ANDURIL INDUSTRIESSenior Manufacturing Software EngineerLexington, MA$191,000–$253,000 / yearThis third-party service provider provides risk-intelligence services that may include analysis of sanctions and watchlists, adverse media, public-record information, and other lawful open-source or commercial data sources. To ensure your safety and help you navigate your job search with confidence, please keep the following critical points in mind: No Financial Requests: Anduril will never solicit payment or demand personal financial details (such as banking information, credit card numbers, or social security numbers) at any stage of our hiring process.
Senior Engineer, Distribution Automation(Hybrid schedule) Eversource EnergySenior Engineer, Distribution Automation(Hybrid schedule)Westwood, MassachusettsIndividual will collaborate with other senior staff members to ensure that the right mix of data communications protocols, technologies, products and services are selected to optimally meet the requirements of an assigned project. Current guidelines require employees to work at least three days in the office, including Tuesdays and Wednesdays, with the third day set by the employee and supervisor based on department needs.
Senior Test Engineer - LabVIEW Software (Automated Test Systems) Excelitas Technologies CorpSenior Test Engineer - LabVIEW Software (Automated Test Systems)Billerica, MA$120,000–$190,000 / yearExcelitas is a global technology leader with more than 7500 employees focused on delivering market-driven solutions to fulfill the illumination optical detection and imaging needs of OEMs and end-users across the biomedical semiconductor industrial consumer products scientific security defense and aerospace sectors. This role is primarily a software engineering position focused on LabVIEW with responsibility for building scalable test architectures integrating complex instrumentation and ensuring reliable high‑quality test coverage across development and production.
Senior Reliability Engineer ANDURIL INDUSTRIESSenior Reliability EngineerWaltham, MA$166,000–$220,000 / yearYour responsibilities will include conducting reliability predictions and allocations during architecture trades, leading design FMEAs and fault tree analyses to identify and mitigate failure modes, developing and executing design verification test plans, performing stress-derating analysis and parts selection reviews, and assessing design changes for reliability impact throughout the development cycle. The right person for this role brings deep technical knowledge of hardware reliability and failure mechanisms, has practical experience on product development programs, and can engage credibly with design engineers and Anduril's subcontractors on technical details while maintaining focus on system-level reliability outcomes.
Sr. Software Engineer (Dev Ops) Wonder Group IncSr. Software Engineer (Dev Ops)Boston, MAWorking collaboratively alongside our existing DevOps and Software Engineering team, you will play a key role in optimizing our hardware provisioning pipelines, our CI/CD workflows, and internal tools that keep our team productive. Our 25+ award-winning restaurant partners span every cuisine you can think of, from Greek to Thai, and come from the minds of the best chefs in the industry-Bobby Flay, José Andrés, Marcus Samuelsson, and more.
Salesforce Software Engineer Brigham and Women's HospitalSalesforce Software EngineerSomerville, MA$75,275.20–$109,553.60 / yearResponsible for the implementation and support of technical solutions, including platform systems that require critical aspects of infrastructure, network, application, database, and security frameworks. The framework is comprised of ten competencies (half People-Focused, half Performance-Focused) and are defined by observable and measurable skills and behaviors that contribute to workplace effectiveness and career success.
Product Development Engineer Hologic IncProduct Development EngineerCambridge, MAWe're now looking for a talented Product Development Engineer to join our dynamic team in Cambridge -someone with a strong passion for Physics, Electronics and Software who thrives on solving complex challenges, driving excellence, and making an impact that truly matters. You'll collaborate closely with a network of third‑party suppliers, contract development organisations, consultants and internal cross‑functional teams to deliver innovative, compliant and manufacturable products.
RF Engineer The Structures Company, LLCRF EngineerAndover, MAAs trusted partners to leading aerospace and defense OEMs and Tier 1 suppliers, we connect professionals with career opportunities to grow and excel in aviation, aerospace, and defense. Expertise in RF subsystems and hardware (antennas, transmitters, receivers, amplifiers, mixers, switches, frequency generation/conversion).
Software Engineer, CAD Automation Reframe SystemsSoftware Engineer, CAD AutomationBoston, MassachusettsThrough our vertically integrated delivery model and highly automated microfactories, we deliver climate resilient homes and buildings with greater speed and predictability than traditional construction. You'll write custom features in and around Onshape (FeatureScript and API driven), and back them with real engineering practices, so the tools you ship run reliably in production and take repeated manual work off the team's plate.
Lead Software Quality Engineer Agile SearchLead Software Quality EngineerWaltham, MassachusettsOur client is seeking a Lead - Senior - Principal, Software Quality Engineer to join a talented team and provide software quality assurance leadership and support for medical device development. In this role, you will facilitate the application of design controls, risk management and usability, with a focus on software, for complex electromechanical medical devices that include sterile, single-use disposables.
Senior Mechanical Engineer (NPI) WhoopSenior Mechanical Engineer (NPI)Boston, MassachusettsYou will work closely with our suppliers and contract manufacturers around the world to execute engineering validation builds with a focus on high quality deliverables, sharp engineering risk management, clear technical communication upwards and externally, and commitment to product excellence. At WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company’s long-term growth and success.
Staff iOS Engineer (Connectivity) WhoopStaff iOS Engineer (Connectivity)Boston, MassachusettsAt WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company’s long-term growth and success. Drive continuous improvement of performance, power efficiency, and reliability in the WHOOP connectivity software layer including background and system-level iOS services to enable reliable device connectivity, synchronization, and data transfer.
NewStaff Mechanical Engineer (NPI) WhoopStaff Mechanical Engineer (NPI)Boston, Massachusetts$175,000–$215,000 / yearYou will work closely with our suppliers and contract manufacturers around the world to execute engineering validation builds with a focus on high quality deliverables, sharp engineering risk management, clear technical communication upwards and externally, and commitment to product excellence. At WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company’s long-term growth and success.
Building Systems Engineer Reframe SystemsBuilding Systems EngineerAndover, MassachusettsThrough our vertically integrated delivery model and highly automated microfactories, we deliver climate-resilient homes and buildings with greater speed and predictability than traditional construction. Our cross-disciplinary team brings together architecture, robotics, design engineering, software, factory operations, and field delivery to change how housing gets delivered.
Staff Ios Engineer (Connectivity) WhoopStaff Ios Engineer (Connectivity)Boston, MA$170,000–$230,000 / yearAt WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company's long-term growth and success. Drive continuous improvement of performance, power efficiency, and reliability in the WHOOP connectivity software layer including background and system-level iOS services to enable reliable device connectivity, synchronization, and data transfer.
Staff Manufacturing Engineer Boston Dynamics, inc.Staff Manufacturing EngineerWaltham, MA$116,000–$140,000 / yearDesign, fabricate, and validate custom fixtures, tools, and jigs to support mechanical assembly, precision alignment, and testing of electric motors and actuators, ensuring ergonomic and repeatable processes. Support prototype builds in a hands-on capacity, troubleshooting assembly issues, identifying root causes, and driving corrective actions to improve processes and product designs.
Staff Mechanical Engineer (Npi) WhoopStaff Mechanical Engineer (Npi)Boston, MA$175,000–$215,000 / yearYou will work closely with our suppliers and contract manufacturers around the world to execute engineering validation builds with a focus on high quality deliverables, sharp engineering risk management, clear technical communication upwards and externally, and commitment to product excellence. At WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company's long-term growth and success.
Senior Mechanical Engineer (Npi) WhoopSenior Mechanical Engineer (Npi)Boston, MA$140,000–$195,000 / yearYou will work closely with our suppliers and contract manufacturers around the world to execute engineering validation builds with a focus on high quality deliverables, sharp engineering risk management, clear technical communication upwards and externally, and commitment to product excellence. At WHOOP, we view total compensation as the combination of base salary, equity, and benefits, with equity serving as a key differentiator that aligns our employees with the long-term success of the company and allows every member of our corporate team to own part of WHOOP and share in the company's long-term growth and success.
Senior Staff Manufacturing Engineer Boston Dynamics, inc.Senior Staff Manufacturing EngineerWaltham, MA$135,000–$170,000 / yearStaff Manufacturing Engineer, you will play a critical role in the optimization and scale-up of low-volume production processes, assembly workflows, and custom tooling to support the assembly, test, and integration of our next-generation humanoid robot. You will work closely with Hardware Engineering, Prototype Operations, Systems Engineering, Behavior and Software teams to ensure that cutting-edge designs can be efficiently and reliably built in a prototype and low-volume production environment.
Senior Staff Manufacturing Test Development Engineer Boston Dynamics, inc.Senior Staff Manufacturing Test Development EngineerWaltham, MA$134,399.06–$184,798.70 / yearJoin us as a Senior Staff Manufacturing Test Engineer in Technical Operations, where you'll architect and implement the critical test systems that bring our groundbreaking robots-Spot, Stretch, and Atlas-to life. Champion Design for Test (DFT): Partner with cross-functional teams to integrate DFT best practices early, optimizing test coverage, fault isolation, and subassembly reliability.
Staff Systems Engineer Merlin LabsStaff Systems EngineerBoston, MAWho you are: You are a very experienced systems engineer involved in systems integration, requirements management, system design, and testing in civil-certified or DOD safety-critical avionics systems. Responsibilities: Guide system development from system requirements capture, through design decision making, to final demonstration for systems being implemented on existing general aviation aircraft.
Coating and Lamination Engineer 1100H-2 E Ink CorporationCoating and Lamination Engineer 1100H-2Billerica, MA$80,000–$110,000 / yearToday, our technology is trusted by customers around the world and powers millions of devices, from eReaders and electronic shelf labels to digital signage, transportation displays, healthcare solutions, and emerging IoT applications. Our teams work across disciplines and around the globe to solve complex problems, develop groundbreaking products, and create technologies that make information more accessible while supporting a more sustainable future.
Systems Engineer ANDURIL INDUSTRIESSystems EngineerQuincy, MA$146,000–$194,000 / yearTo ensure your safety and help you navigate your job search with confidence, please keep the following critical points in mind: No Financial Requests: Anduril will never solicit payment or demand personal financial details (such as banking information, credit card numbers, or social security numbers) at any stage of our hiring process. This third-party service provider provides risk-intelligence services that may include analysis of sanctions and watchlists, adverse media, public-record information, and other lawful open-source or commercial data sources.
Staff System Applications Engineer - RF Analog Devices IncStaff System Applications Engineer - RFChelmsford, MA$124,721–$180,602 / yearFor positions requiring access to technical data, Analog Devices, Inc. may have to obtain export licensing approval from the U.S. Department of Commerce - Bureau of Industry and Security and/or the U.S. Department of State - Directorate of Defense Trade Controls. ADI combines analog, digital, and software technologies into solutions that help drive advancements in digitized factories, mobility, and digital healthcare, combat climate change, and reliably connect humans and the world.
Field Service Professional - Thornton, CO Home DepotField Service Professional - Thornton, COColoradoThe Field Service Professional is a skilled technician, adept at performing a full range of equipment repairs on light repairs and maintains a variety of industrial equipment found within Home Depot and external customers' retail locations and manufacturing facilities, such as but not limited to paint shakers, carpet carousels, checkout stands, blind cutting machines, shopping carts, lifts, and more. Typically in a comfortable environment but with regular exposure to factors such as temperature extremes, moving machinery, loud noise, and fumes which cause noticeable discomfort or a moderate risk of accident or illness.