Senior Software Engineer GCR Professional ServicesSenior Software EngineerWoburn, MassachusettsContractorHave domain expertise in one or more of the following areas: electronic warfare, antenna apertures, sensor resource management, large-scale platform test systems, cyber physical systems, open system architectures. Systems Development Division (SDD) executes the entire lifecycle of the solution, from conceptualization and architecture refinement through implementation and deployment, while leveraging novel technologies to deliver first-of-a-kind systems.
Embedded Software Engineer (Avionics) GCR Professional ServicesEmbedded Software Engineer (Avionics)Cambridge, MassachusettsContractorExcellent development and troubleshooting skills on embedded targets ¿ Excellent knowledge of OS coding techniques, interfaces, hardware subsystems and driver development ¿ Development experience with device drivers, board support package, boot code and knowledge of embedded system buses and protocols (e.g. GCC, LLVM), static analysis tools, dynamic analysis, and QEMU based development are preferred ¿ Knowledge and experience with software configuration management tools, defect tracking tools, and peer review processes.
NewSenior Lead AI Software Engineer KlaviyoSenior Lead AI Software EngineerBoston, MA$216,000–$324,000 / yearAs a Senior Lead Software Engineer on Amplify, you will: Independently own and drive high-impact objectives that span multiple Amplify teams and align with company priorities, defining the technical roadmap that ensures our internal applications, APIs, data and event pipelines, and AI-powered workflows can scale with Klaviyo and continue delivering measurable business outcomes. Independently lead the end-to-end lifecycle of large, multi-team initiatives with clear technical direction, architectural leadership, and active workstream curation, from discovery and design through implementation, rollout, and long-term ownership of complex programs that span internal customers across the company.
NewSoftware Engineer (C# .NET Framework/SQL Server) SarnovaSoftware Engineer (C# .NET Framework/SQL Server)Boston, MAThe position is well suited for an engineer who enjoys working with complex systems, troubleshooting production issues, and contributing to the continued evolution and sustainability of the platform. This role focuses on supporting, enhancing, and progressively modernizing enterprise and legacy applications using C#, NET Framework, and SQL Server.
NewPrincipal Software Engineer, Enterprise Scalability KlaviyoPrincipal Software Engineer, Enterprise ScalabilityBoston, MA$244,000–$366,000 / yearAI‑assisted scale engineering: AI‑driven anomaly detection reduces alert noise while improving signal; generative load testing and copilot runbooks are used in release/readiness checks for the top critical services; time‑to‑isolate regressions drops 20–30%. In addition to base salary, our total compensation package may include participation in the company’s annual cash bonus plan, variable compensation (OTE) for sales and customer success roles, equity, sign-on payments, and a comprehensive range of health, welfare, and wellbeing benefits based on eligibility.
NewForward Deployed Engineer JobotForward Deployed EngineerBoston, MA$160,000–$300,000 / yearOur client is a leading data analytics and technology consulting firm that partners with private equity firms and their portfolio companies to solve complex business challenges through AI, advanced analytics, and modern data engineering. Information collected and processed as part of your Jobot candidate profile, and any job applications, resumes, or other information you choose to submit is subject to Jobot's Privacy Policy, as well as the Jobot California Worker Privacy Notice and Jobot Notice Regarding Automated Employment Decision Tools which are available at jobot.com/legal.
Robotics/Controls Engineer GCR Professional ServicesRobotics/Controls EngineerBurlington, Massachusetts$100,000–$140,000 / yearCollaborate with the Manager of Controls Engineering to design and implement advanced control systems for robotic manipulators and electromechanical systems. Responsibilities include motion control and servo tuning, dynamic modeling, simulation in MATLAB, and real-time software implementation.
Senior Mechanical Engineer SymboticSenior Mechanical EngineerMedford, MAApplying next-gen technology, high-density storage and machine learning to solve today's complex distribution challenges, Symbotic enables companies to move goods with unmatched speed, agility, accuracy and efficiency. Cross-Functional Collaboration: Work closely with electrical, software, controls, manufacturing, and quality engineering teams to ensure seamless integration and product success. .
NewManufacturing Applications Engineer JobotManufacturing Applications EngineerWorcester, MA$90,000–$120,000 / yearInformation collected and processed as part of your Jobot candidate profile, and any job applications, resumes, or other information you choose to submit is subject to Jobot's Privacy Policy, as well as the Jobot California Worker Privacy Notice and Jobot Notice Regarding Automated Employment Decision Tools which are available at jobot.com/legal. This role is responsible for designing and modifying bearing components and assemblies to meet customer requirements while ensuring manufacturability, quality, and cost efficiency.
Model-Based Systems Engineer (MBSE) GCR Professional ServicesModel-Based Systems Engineer (MBSE)Woburn, Massachusetts$75–$90 / hourContractorRole can be Hybrid, TBD The Systems Engineer should have experience architecting systems, working across the Systems Engineering Lifecycle, and in Digital Engineering/Model-Based Systems Engineering (MBSE) achieving architectural integrity and traceability through requirements analysis, system and software development and production system deployment. The ideal candidate will be well-versed in Systems Engineering techniques, Modeling and Simulation, and Digital Engineering/MBSE and be excited about opportunities to mentor more junior staff and help foster growth of subject matter expertise across the organization.
NewApplication Engineer GCR Professional ServicesApplication EngineerBillerica, Massachusetts$95,000–$130,000 / yearJob Summary: This role is responsible for translating customer technical requirements into product specifications, designing and validating new features, and developing custom mechanical components. It also includes maintaining technical documentation, providing on-site support, and collaborating cross-functionally to ensure successful product implementation.
Manufacturing Engineer III| (NH) GCR Professional ServicesManufacturing Engineer III| (NH)Hudson, New HampshireContractorYou will collaborate with cross-functional teams, including design engineers, production personnel, and quality assurance, to optimize manufacturing operations and drive continuous improvement initiatives. As a Manufacturing Engineer, your primary responsibility will be to develop and improve manufacturing processes and systems to ensure the efficient and cost-effective production of defense and aerospace products.
Manufacturing Engineer III (NH) GCR Professional ServicesManufacturing Engineer III (NH)Hudson, New HampshireContractorYou will collaborate with cross-functional teams, including design engineers, production personnel, and quality assurance, to optimize manufacturing operations and drive continuous improvement initiatives. As a Manufacturing Engineer, your primary responsibility will be to develop and improve manufacturing processes and systems to ensure the efficient and cost-effective production of defense and aerospace products.
NewSenior Supplier Quality Engineer GCR Professional ServicesSenior Supplier Quality EngineerBillerica, Massachusetts$120,000–$140,000 / yearThis role serves as the primary quality liaison between the company and its suppliers, partnering with Procurement, Engineering, Operations, and Manufacturing teams to drive supplier qualification, audits, compliance, continuous improvement, and defect prevention. Manage supplier quality metrics, including defect rates, non-conformance reports (NCRs), corrective actions, and supplier performance indicators.
RF Engineer III (NH) - Security Clearance GCR Professional ServicesRF Engineer III (NH) - Security ClearanceHudson, New HampshireContractorCollaboration: Collaborate with cross-functional teams, including electrical engineers, mechanical engineers, software engineers, and project managers, to ensure successful integration of the Antennas. *Testing and Measurement Equipment: - Experience with Antenna/RF testing and measurement equipment, such as network analyzers, spectrum analyzers, signal generators, and oscilloscopes.
NewCOMPONENT ENGINEER GCR Professional ServicesCOMPONENT ENGINEERCambridge, MassachusettsContractorComponent Types Supported Resistors, capacitors, diodes, ICs, hybrids, crystal oscillators, filters, fuses, heaters, magnetics, microcircuits, relays, semiconductors, thermistors, and other EEE hardware. Seeking an experienced Electrical, Electronic, and Electromechanical (EEE) Component Engineer to support the development of high reliability electronic systems for demanding aerospace and defense applications.
Guidance, Navigation & Control Engineer for Space GCR Professional ServicesGuidance, Navigation & Control Engineer for SpaceCambridge, MassachusettsRemoteContractorThe applicant will join a team of highly motivated Guidance, Navigation and Control (GNC) Engineers in the design, development, test, implementation and operation of spacecraft GNC systems for Low Earth Orbit space missions. Qualifications should include: MS degree in a relevant technical field of study, plus at least 4 years applicable experience or a PhD degree in a relevant technical field of study.
MS Azure Engineer Continental ResourcesMS Azure EngineerBedford, MAFull timeA successful candidate has strong experience with Azure Cloud services, is self-driven, enjoys learning new technologies, and is willing to stretch themselves to become a stronger engineer and mentor others around them to do the same. Developing effective cloud infrastructure, enforcing good architectural principles, providing technical oversight, and ensuring security best practices are implemented and followed.
Principal Radar Systems Engineer GCR Professional ServicesPrincipal Radar Systems EngineerWoburn, MassachusettsContractorClient is focused on delivering National Defense capabilities by driving mission-focused strategies to develop advanced technology systems enabling enduring products and solutions focused on achieving the customer vision. Applicants are expected to be self-motivated, detail oriented and have a demonstrated ability to effectively communicate with all levels of management and individual contributors on the program team through strong written and verbal communication skills.
Quality Engineer III (NH) GCR Professional ServicesQuality Engineer III (NH)Hudson, New Hampshire$45–$58 / hourContractorThis role will participate and/or lead failure analysis in manufacturing and for field failures, develop troubleshooting & repair schemes, develop manufacturing process controls and documentation, interface with manufacturing and quality personnel to train and transfer processes & knowledge for successful volume production launches, and engage with suppliers as needed to drive improvement and implement process controls. This is a hands-on role that works with a team of quality engineers, technicians and inspectors that are engaged through the entire life cycle of product, starting during development, continuing with transitioning of product to manufacturing, and then supporting the continuous manufacture of product.
GNC SYSTEMS ANALYST ENGINEER GCR Professional ServicesGNC SYSTEMS ANALYST ENGINEERCambridgeContractorTime domain simulations, covariance-based methods, and Monte Carlo dispersed analysis will be used to assess and tune system performance and to document analysis results. The analysis will include assessment of control, navigation, and guidance system performance, verification of algorithms and algorithm requirements, and analysis of flight dynamics and trajectory dispersions.
Test Engineer, Senior - Secret DCS CorporationTest Engineer, Senior - SecretBedford, MA$90,220–$165,000 / yearThe Electronic Systems System (ESS) Division aka Force Protection Division's mission responsibility is to manage and execute the modernization, design, development, testing, fielding, and sustainment of the various software and hardware within the ESS Portfolio. Evaluate test environments to ensure they are properly configured and capable of supporting software release testing, including fault insertion and fault identification activities.
NewCybersecurity Engineer, Senior - Secret DCS CorporationCybersecurity Engineer, Senior - SecretBedford, MA$90,220–$210,000 / yearEssential Job Functions : Assist in the development of security documentation including System Security Management Plans, Program Protection Plans, Security Risk Analyses, OPSEC Plans, and other required system security engineering artifacts. The Electronic Systems System (ESS) Division aka Force Protection Division's mission responsibility is to manage and execute the modernization, design, development, testing, fielding, and sustainment of the various software and hardware within the ESS Portfolio.
STS Senior Test Development Engineer P4 Butler America AerospaceSTS Senior Test Development Engineer P4Tewksbury, MA$80–$94 / hourDesired Skills (Nice to Have)Experience with project leadership, project cost and schedule management, i.e. EVMS, MS ProjectDoW (DoD) project development life cycle processes. The individual comes up to speed quickly, has an impact on our projects developing test stations/fixtures/automated test software, has familiarity with a process heavy work environment.
General/Interdisciplinary Engineer, Senior - Secret DCS CorporationGeneral/Interdisciplinary Engineer, Senior - SecretBedford, MA$90,220–$170,000 / yearConduct systems architectural analyses to include system design/design feasibility and state-of-the-art assessment to Produce architectures, document planned and existing systems, determine deficiencies, develop alternatives, recommend solutions, and support development of a plan to implement the chosen solution per acquisition and sustainment system engineering processes. Analysis of Alternatives (AoA), Systems Engineering Plan (SEP)…), systems review and analysis with written reporting, briefing, and artifact development as required for all of the technical specialty areas defined in this section; and the planning and execution of all necessary technical reviews, assessments, and interchange meetings (e.g.
NewElectrical Engineer Davron LLCElectrical EngineerFranklin, MASENIOR ENGINEER, ELECTRICAL | FRANKLIN, MA | PTC Creo | SolidWorks | GD&T | ASME Y14.5 | U.S. DoD security clearance | ELECTRICAL ENGINEERING | PROTOTYPE BUILDS | INTEGRATION | TESTING | SUSTAINMENT . This Electrical Engineer role offers the chance to lead electrical system design, integration, testing, and sustainment across complex mission systems from concept through production transition.
NewPrincipal Digital Signal Processing Systems Engineer GCR Professional ServicesPrincipal Digital Signal Processing Systems EngineerCambridge, MassachusettsContractorAs Principal Signal Processing System Engineer you will work directly with customers and program managers to create innovative, multidisciplinary technical solutions, for a broad range of highly-complicated mission needs. You will have hands-on engagement with prototype development, which may include software or firmware coding, test equipment operation and programming, integration and validation, and field tests and customer demonstrations.
Systems Engineer, Junior - TS DCS CorporationSystems Engineer, Junior - TSBedford, MA$73,160–$115,000 / yearThe C2ISR Division provides worldwide life cycle support across the spectrum of the C2ISR capabilities based enterprise; including supply, distribution, materiel management, acquisition, system engineering and maintenance, financial planning and budgeting, security, flight test, and contracting functions. Experienced in requirements development, production and deployment, and operation and support, architectures development & implementation, modeling & simulation including but not limited to Model Based Systems Engineering principles, verification & validation, technical data package development and sustainment, and principles of configuration management.
RF Engineer Butler America AerospaceRF EngineerMaynard, MA$82–$97 / hourContractorExpertise with RF subsystems and hardware including antennas, transmitters, receivers, microwave components, low noise amplifiers, high power amplifiers, advanced electronic modules, amplifiers, mixers, switches, frequency generation circuits, and frequency conversion circuits is desired. -The engineering will collaborate with other engineering disciplines including hardware engineers, systems engineers, and circuit design engineers as well as technical and manufacturing support personnel.
Cybersecurity Engineer DCS CorporationCybersecurity EngineerBedford, MA$90,220–$175,000 / yearUnder the Department of the Air Force Program Executive Office for Command, Control, Communication, and Battle Management (DAF PEO C3BM), Kessel Run technologies make up the DAF BATTLE NETWORK, the systems-of-systems designed to help the Joint Force make operational decisions faster than our adversaries. The Assured Compliance Assessment Solution (ACAS) Cybersecurity Engineer will be a member of the Air Operation Center (AOC) cybersecurity team and will be responsible for assisting with the implementation, maintenance, and operation of the Assured Compliance Assessment Solution (ACAS) suite of tools.
NewStaff Electrical Engineer - Substation Gables Search GroupStaff Electrical Engineer - SubstationNewton, MA$120,000–$150,000Come join a collaborative team shaping the future of energy infrastructure — with real opportunities for career growth, hands-on mentorship, and the chance to work on high-impact projects that strengthen the power grid for the communities that depend on it. We're seeking a Staff Electrical Engineer to support the design and engineering of high-voltage substations (13kV–500kV) for projects across the U.S. and internationally.
NewSenior Engineer (Product) LaterSenior Engineer (Product)Boston, MARemote$125,000–$205,000 / yearBy combining trusted insight with expert guidance, Later removes guesswork from influencer marketing, enabling brands to choose the right creators, execute fully managed campaigns, and drive meaningful growth across awareness, engagement, and revenue. Built on a native, AI-powered platform and more than a decade of proprietary data—including billions of social interactions, impressions, and $2.4B+ in verified influencer-driven purchases—Later helps teams understand what will work before they launch.
NewManager, Cloud Engineer - Terraform KPMGManager, Cloud Engineer - TerraformBoston, MAQualifications: Minimum five years of recent experience in IT infrastructure technology management and architecture including IaaS/PaaS/DevOps cloud transformation programs and infrastructure automation, prior system/storage; admin/engineering experience and consulting experience; four years of cloud strategy, migration, and transformation leadership including cloud services (IaaS/PaaS) implementation & migration, including Azure or AWS. Additional desirable experience in infrastructure automation and instrumentation (Unix Admin, Scripting / Programming Capabilities, SDLC Process Knowledge), Unified Communications, Collaboration, Database/application server architecture, network, information security, GenAI, RAG.
Systems Engineer - TS Clearance System OneSystems Engineer - TS ClearanceBedford, MA$140,000–$150,000 / hourConduct reviews on program portfolio to evaluate and/or recommend alternative plans, improve systems engineering programs/processes, manage/sustain program technical baseline, and design/perform system level tests to ensure subsystem and system performance in accordance with specifications. Perform program reviews to evaluate proposed plans, systems engineering programs, design, and test results, ensuring performance is met per program requirements.
NewMechanical Engineer - Lowell, MA Michael Page USAMechanical Engineer - Lowell, MALowell, MA$90,000–$110,000 / yearFull timeThe organization values technical expertise, continuous improvement, and practical problem-solving, making it an excellent opportunity for engineers who enjoy working on complex products in a fast-paced setting. This role offers the opportunity to manage projects throughout the product lifecycle while working closely with cross-functional teams on new product development, testing, and continuous improvement initiatives.
Aerospace - Mechanical Engineer - Chelmsford, MA Michael Page USAAerospace - Mechanical Engineer - Chelmsford, MAChelmsford, MA$110,000–$120,000 / yearFull timeOur client is a well-established manufacturer of specialized electronic protection and filtering solutions serving a diverse customer base across commercial, industrial, and defense markets. Our client is seeking a Mechanical Design Engineer to support the design, development, testing, and documentation of specialized electronic hardware products.
NewMechanical Engineer - Defense - Wilmington, MA Michael Page USAMechanical Engineer - Defense - Wilmington, MAWilmington, MA$100,000–$130,000 / yearFull timeWorking closely with engineering, production, quality, and product management teams, the successful candidate will contribute throughout the entire product lifecycle, from concept generation and prototyping to validation, manufacturing support, and project delivery. The Mechanical Design Engineer will be responsible for designing, developing, testing, and documenting specialised products while supporting both new product development and ongoing product improvements.
Sr. Engineer - TS Clearance System OneSr. Engineer - TS ClearanceBedford, MA$155,000–$175,000 / hourSupport digital engineering concepts and techniques throughout the program lifecycle, including Model Based Systems Engineering (MBSE). System One, and its subsidiaries including Joulé and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America.
NewSenior Associate, Privileged Access Management Delivery Engineer KPMGSenior Associate, Privileged Access Management Delivery EngineerBoston, MA$95,855–$208,265 / yearImplement and maintain PAM capabilities including privileged credential management, session management, just-in-time access, and endpoint management (EPM)components; implement automated integration across adjacent security solutions (for example: Crowdstrike, SIEM solutions, ServiceNow); automate PAM tasks using scripting and APIs (such as PowerShell, Python, REST, and others) and integrate with enterprise platforms (that is, Active Directory, IdPs, ITSM platforms, SIEM platforms, and more). Hands on experience with Privileged Access Management delivery and engineering, with specific experience using CyberArk On-Prem and SaaS solutions; additional experience with secrets management platforms (that is, Conjur, HashiCorp) and other PAM platforms (such as Delinea, BeyondTrust) preferred.
Manufacturing Engineer | Propulsion Technologies Michael Page USAManufacturing Engineer | Propulsion TechnologiesBoston, MA$130,000–$195,000 / yearFull timeWe are seeking an experienced Senior Manufacturing Engineer to drive manufacturing process development, operational efficiency, and continuous improvement initiatives supporting aerospace propulsion and flight hardware programs. Team members play a key role in ensuring mission success through the development, testing, and deployment of high-reliability hardware designed to perform in the harsh conditions of space.
NewSenior Manufacturing Engineer in Lexington, MA Michael Page USASenior Manufacturing Engineer in Lexington, MALexington, MA$145,000–$146,000 / yearFull timeAn exciting opportunity for a Manufacturing Engineer to drive process optimization, operational excellence, and continuous improvement within a cutting-edge manufacturing environment supporting advanced engineered components. Backed by a culture of innovation and continuous improvement, the organization combines cutting-edge technology, research-driven development, and scalable manufacturing to deliver high-performance solutions.
Aerospace/Defense - Sr. Manufacturing Engineer - Greater Boston Michael Page USAAerospace/Defense - Sr. Manufacturing Engineer - Greater BostonBoston, MA$130,000–$180,000 / yearFull timeThis individual will play a key role in developing robust manufacturing processes, designing and improving tooling and fixturing solutions, and supporting the production of highly engineered hardware in a regulated, precision-focused environment. Our client is seeking a Senior Manufacturing Engineer to drive process development, production support, and continuous improvement initiatives across advanced manufacturing operations.
NewSenior Manufacturing Engineer in Wakefield, MA Michael Page USASenior Manufacturing Engineer in Wakefield, MAWakefield, MA$130,000–$145,000 / yearFull timeAs they continue to expand into new markets and applications, they are investing in top technical talent who can help drive operational excellence, improve production scalability, and support long-term business growth. Our client is a rapidly growing advanced manufacturing company that specializes in delivering precision-engineered solutions for customers across a variety of innovative and technology-driven industries.
Senior Electrical Engineer - Industrial - Danvers, MA Michael Page USASenior Electrical Engineer - Industrial - Danvers, MADanvers, MA$125,000–$180,000 / yearFull timeMy client is a global technology leader in semiconductor manufacturing equipment, providing innovative solutions that enable the production of advanced chips used in consumer electronics, automotive applications, communications, and industrial technologies. The Senior Electrical Engineer is responsible for the design, development, and support of complex electrical and electromechanical systems used in advanced semiconductor manufacturing equipment.
NewSenior Project Manager (Custom Software & Healthcare) JobotSenior Project Manager (Custom Software & Healthcare)Chestnut Hill, MA$120,000–$200,000 / yearInformation collected and processed as part of your Jobot candidate profile, and any job applications, resumes, or other information you choose to submit is subject to Jobot's Privacy Policy, as well as the Jobot California Worker Privacy Notice and Jobot Notice Regarding Automated Employment Decision Tools which are available at jobot.com/legal. Rather than supporting a single product, you'll partner with innovative healthcare organizations to design and deliver technology that improves patient experiences, provider workflows, and healthcare outcomes.
Process Engineer - Chemical Manufacturing - Foxborough, MA Michael Page USAProcess Engineer - Chemical Manufacturing - Foxborough, MAFoxborough, MA$95,000–$115,000 / yearFull timeAn established manufacturing organization is seeking a Chemical Process Engineer to drive process optimization, equipment improvements, and capital projects within a complex chemical production environment. Deliver capital expenditure projects including equipment upgrades, process improvements, facility enhancements, and replacement programs.
NewChemical Process Engineer - Foxborough, MA Michael Page USAChemical Process Engineer - Foxborough, MAFoxborough, MA$95,000–$115,000 / yearFull timeEmployees have the opportunity to make a visible impact through process enhancements, equipment improvements, and strategic capital projects while developing their technical expertise within a supportive environment. The company invests in advanced production technologies and provides employees with opportunities to contribute to meaningful engineering projects that improve efficiency, safety, and sustainability.
NewAssociate or Senior Associate, Fixed Assets / Cost Segregation Engineer (AMCS) KPMGAssociate or Senior Associate, Fixed Assets / Cost Segregation Engineer (AMCS)Boston, MAStrong proficiency in Excel (such as advanced formulas, pivot tables, lookups) and experience working with structured data from financial or operational systems; demonstrated experience or strong aptitude with data wrangling/automation tools (such as, Power Query, Alteryx), business intelligence tools (such as Power BI, Tableau), or query/scripting languages (such as SQL, Python, R). Additional Qualifications for Senior Associate: Minimum two years of recent experience in an engineering firm, corporation, or public accounting firm; background in cost segregation, fixed asset consulting, construction, engineering, or a related technical field.
NewSR Cloud Security Engineer BJ's Wholesale ClubSR Cloud Security EngineerMarlborough, MA$100,000–$131,500This is a hands‑on engineering role responsible for evaluating cloud and application designs, operating cloud security tooling, and driving remediation of security findings in partnership with engineering and platform teams. Support and continuously improve enterprise vulnerability management and patching workflows, including SLAs, exception handling, and escalation paths.
Principal Front-Office Engineer AxelonPrincipal Front-Office EngineerBoston, MAAs a Principal Front-Office Engineer, you will serve as the technical lead embedded within the Risk team, driving design and implementation of small-scale applications and proof of concepts that will improve risk analysis, develop AI-enabled workflows, and enhance reporting systems & processes. Strong SQL skills required with a familiarity of financial data platforms (such as Bloomberg, FactSet, Aladdin, eFront, Moodys), financial databases, and data manipulation techniques preferred.