Jobs in Canada

Lead Senior React Developer in Toronto

143 active opportunities · Updated October 2026

Explore current lead senior react developer jobs in Toronto. Filter by work mode, employment type, experience, department, date posted and distance.

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📍 Toronto, Ontario, Canada· Full-time
✓ High-confidence listingCompany trend -100%

$100K – $125K/yr

Quick readStrong listing-quality and freshness signals

About Sentry Software runs the world and the pace is faster than ever. Sentry helps developers fix errors and performance issues before users notice, so teams can spend less time firefighting and more time building. Trusted by 200,000+ organizations, Sentry is today’s application monitoring standard and our team is building its AI-native future. About the Role At Sentry, Support is an engineering discipline. Our customers are the greatest technical minds in the world—developers at elite enterprises building the future of software—and they deserve answers that go deeper than a knowledge base link. We are architecting the Technical Support engine . We’re looking for a veteran engineer to help us redefine the standard of technical support by combining deep human expertise with autonomous agentic systems. You are a debugger of both code and systems. You will treat support volume as a data signal to build automated resolution paths, ensuring our human engineers only touch the most complex, high-impact architectural puzzles. Sentry Support Engineers aren't just clearing queues; they are Orchestrators . You will engage with our users across GitHub, Discord, and our internal systems, while acting as the Technical Lead for our Agentic Ops. You ensure that when a developer asks a complex question, our systems have the right context and a seamless "Human-in-the-Loop" path to you when deep, nuanced expertise is required. In this role you will Master the Sentry Ecosystem & Support Elite Developers Deep-Dive Debugging: Perform root-cause analysis on complex issues and distributed tracing gaps across polyglot environments. Support the Great Minds: Act as a strategic consultant for senior engineers at our largest enterprise customers, solving high-stakes architectural challenges that push the boundaries of observability. Troubleshoot SDK Implementations: Go deep into the source code of Sentry’s SDKs to help developers instrument complex frameworks and custom environments. Engin

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📍 Toronto, Ontario, Canada· Full-time· Remote
✓ Quality checkedCompany trend -100%

At Vanta, our mission is to help businesses earn and prove trust. We believe that security should be monitored and verified continuously, and we empower companies to practice better security and prove it with ease. Vanta has a kind and talented team, and while some have prior security experience, many have been successful at Vanta without it. Our Senior Software Engineers lead and mentor engineers, delivering high-value products for our customers and infrastructure that enables our business to scale. Vanta’s team and technology surface are growing quickly, and it’s essential that we invest in the right abstractions and systems to enable us to scale with our business. As a Senior Software Engineer, you’ll be responsible for setting technical direction to enable our product and infrastructure to scale with our business, driving complex projects across our technical stack, and mentoring our talented engineering team. Your past experience will be leveraged to enable and accelerate Vanta’s growth. Our business has found incredible product-market fit and has monetized effectively since the day we signed our first customer. We’re growing at a blistering pace, which presents career-defining opportunities for engineers to accelerate their growth and to contribute to a rapidly-scaling company. Visit our Vanta Engineering Blog to learn more about what our team is working on! The Integrations Platform team mission is to power the world’s largest trust automation ecosystem, enabling any person or agent to build, connect, and automate trust seamlessly. We own Vanta’s integration ecosystem, which currently includes over 400 integrations across Cloud Providers (AWS, Azure, GCP), Identity Providers, Mobile Device Management (MDM), and Human Resources Information System (HRIS). We are focused on developing the Integration Platform. This includes creating shared primitives for authentication, lifecycle, observability, and publishing to ensure all integrations are built on the same fou

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📍 Toronto, Ontario, Canada· Full-time
✓ Quality checkedCompany trend -100%

At Vanta, our mission is to help businesses earn and prove trust. We believe that security should be monitored and verified continuously, and we empower companies to practice better security and prove it with ease. Vanta has a kind and talented team, and while some have prior security experience, many have been successful at Vanta without it. Our Senior Software Engineers lead and mentor engineers, delivering high-value products for our customers and infrastructure that enables our business to scale. Vanta’s team and technology surface are growing quickly, and it’s essential that we invest in the right abstractions and systems to enable us to scale with our business. As a Senior Software Engineer, you’ll be responsible for setting technical direction to enable our product and infrastructure to scale with our business, driving complex projects across our technical stack, and mentoring our talented engineering team. Your past experience will be leveraged to enable and accelerate Vanta’s growth. Our business has found incredible product-market fit and has monetized effectively since the day we signed our first customer. We’re growing at a blistering pace, which presents career-defining opportunities for engineers to accelerate their growth and to contribute to a rapidly-scaling company. Visit our Vanta Engineering Blog to learn more about what our team is working on! Please note we are only able to hire in Alberta, Ontario, and British Columbia. The GRC (Governance, Risk and Compliance) organization is the primary org responsible for developing and maintaining Vanta's core product offerings. These teams are at the heart of Vanta moving upmarket to support enterprise customers and build products that enable our customers’ existing security and compliance programs to integrate seamlessly with Vanta, giving them invaluable insights and recommendations to continue to operate, mature and evolve their programs. What you’ll do as a Senior Software Engineer at Vanta: Lead comp

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📍 Toronto, Canada· Full-time
✓ High-confidence listing

From C$1.6M/yr

Quick readStrong listing-quality and freshness signals

About the Role: The team is responsible for building and optimizing the UI/UX across all Web and OTT applications at Tubi. The team primarily focuses on implementing features related to user acquisition and growth, including but not limited to user registration, onboarding, SEO, and account management. As part of this team, you will work closely with Product and Design to develop cutting-edge, experiment-driven features that enhance the user experience. In addition to front-end development, you’ll be responsible for building the underlying technical architecture to ensure performance and scalability, while proactively exploring engineering-driven features and experiments that can drive user growth. You will be working with React, Node.js, GitHub Actions, Terraform, and CDN infrastructure to build and deploy high-performance applications that reach millions of users. This is a hybrid role based out of our Toronto office. You must be willing to travel to our Toronto office two days/week. What You'll Do: Work with product management and other stakeholders (Backend, Product, and UI/UX) to iterate on new growth-related features, including registration, onboarding, and SEO. Lead the technical architecture and implementation of scalable and resilient applications that run on multiple platforms, such as web, mobile web, and smart TV devices. Lead and drive innovation in building experiment-driven features that push the boundaries of user experience in streaming. Consistently ship features and improvements across Web and OTT apps with minimal guidance, collaborating with cross-functional teams to deliver high-impact updates. Identify and implement improvements in shared UI components, platform-specific optimizations, and overall front-end infrastructure. Take ownership of the codebase and proactively identify opportunities for refactoring and development process improvement. Mentor and collaborate with fellow engineers, sharing technical expertise and contributi

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📍 Toronto, Canada· Full-time
✓ High-confidence listing
Quick readStrong listing-quality and freshness signals

About Forma.ai: Forma.ai is a Series B startup that's revolutionizing how sales compensation is designed, managed and optimized. We handle billions in annual managed commissions for market leaders like Edmentum, Stryker, and Autodesk. Our growth has been fuelled by our passion for fundamentally changing and shaping how companies use sales intelligence to drive business strategy. We’re welcoming equally driven individuals who are excited about creating something big! Senior Staff Backend Engineer About the Team We build enterprise software that helps organizations optimize sales performance, enabling go-to-market agility. Our engineering organization includes multiple product application teams responsible for delivering core customer-facing capabilities. We are seeking a Senior Staff Backend Engineer to join our application teams and help set technical direction across multiple domains within engineering. You'll work alongside staff, senior, and early-career engineers, and partner closely with engineering leadership to define, evolve, and scale the systems that power enterprise-grade product workflows. This is an opportunity to own complex, multi-domain technical problems and shape product direction beyond a single team. We are low on meetings, high on accountability. Most of the teams are in the EST time zone, but we have a few located in AST, PST, and Central as well. What you'll be doing You will play a pivotal role in shaping the technical direction of our application stack across multiple domains. You will lead development efforts for our most complex initiatives, the kind that span two or more teams or product areas, and serve as a technical benchmark for system design, code quality, and long-term maintainability. You'll operate at the intersection of data modelling, business logic, and enterprise-scale reliability, and your work will often set standards that neighboring teams adopt. This remains a hands-on

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📍 Toronto, Ontario, Canada· Full-time
✓ High-confidence listingCompany trend -67.1%

From C$160K/yr

Quick readStrong listing-quality and freshness signals

Secure Every Identity, from AI to Human Identity is the key to unlocking the potential of AI. Okta secures AI by building the trusted, neutral infrastructure that enables organizations to safely embrace this new era. This work requires a relentless drive to solve complex challenges with real-world stakes. We are looking for builders and owners who operate with speed and urgency and execute with excellence. This is an opportunity to do career-defining work. We're all in on this mission. If you are too, let's talk. The Streaming Foundations team builds services and operates data pipeline infrastructure to support event streaming, messaging, and analytics use cases. We are looking for a Software Engineer who is passionate about distributed systems, platform engineering, and solving data-intensive problems at scale. In this high-impact role, you will get to work with engineers throughout the organization to build foundational infrastructure that allows Auth0 to scale for years to come. What you’ll be doing Help set the technical direction for the team and influence the engineering roadmap for the Platform’s streaming capabilities Design and lead the implementation of our most complex and critical systems for data-intensive use cases. Research and champion new technologies and architectural patterns to solve strategic challenges and scale the platform. Lead and influence cross-functional initiatives, ensuring technical alignment and successful execution across multiple teams. Improve the operational posture of our systems by designing for observability, reliability, and scalability, and by mentoring others in operational best practices. Coach and mentor senior engineers and act as a technical leader across the engineering organization. Collaborate with different stakeholders like product teams whenever needed. What you’ll bring to our teams 7+ years of software development experience in a fast-paced, agile environment Experience working with Golang or Java is preferred H

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📍 Toronto, Canada
✓ Quality checkedCompany trend -74.4%

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. As a Senior Software Engineer, Data on the Mapping team, you will collaborate with our world-class team of engineers, product managers, and scientists to grow and improve the quality of recommended routes and accuracy of our travel time estimations. You will lead the architecture and long-term technical direction of our offline experimentation tooling and route simulation services — the systems that let Lyft test routing changes safely before they reach production. You'll also build scalable data pipelines for experimentation, analytics, and machine learning models, along with the data governance and observability systems that keep them trustworthy. Your work will enable integration with partner teams and allow stakeholders across Engineering, Data Science, and Product to make data-informed decisions that directly impact Lyft’s growth and profitability. Our technology stack is based on the latest technologies such as AWS, Databricks, Kubernetes and Airflow. You will work with incredibly passionate and talented colleagues from software engineering, machine learning and data science on projects that directly impact millions of riders and drivers. Responsibilities Own core data pipelines end-to-end, building deep subject matter expertise in the systems you manage and defining/managing SLAs for pipelines, services, and datasets to ensure reliability at scale Serve as the technical owner and architectural lead for our offline experimentation platform and route simulation services, setting technical direction, evaluating trade-offs, and ensuring the systems scale with Lyft's routing and mapping ambitions Continuously evolve data models and schemas to meet business and engineering requirements Develop AI tools that support self-service management of data pipelines (ETL) and schema evolution, and perform han

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📍 Toronto, Canada· Full-time
✓ High-confidence listingCompany trend -74.4%

From C$122K/yr

Quick readStrong listing-quality and freshness signals

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Lyft is hiring a Senior Financial Data Analyst to lead the Reporting sub-team within Finance Data & Insights. This sub-team is core to ensuring all key Run the Business (RTB) financial reports are complete, accurate, and operationally reliable on a day-to-day basis. The mandate is two-fold: build repeatable systems, playbooks, and documented workflows that reduce reactive work, and own the primary stakeholder relationships for RTB work across teams. This is a high-visibility role that combines hands-on ownership of critical reporting with team leadership and process-building. Responsibilities: Own all RTB and Compliance reporting (tax, airports, audit requests, etc.), ensuring accuracy, completeness, and operational reliability Build and maintain process documentation, checklists, and operational playbooks that make reporting workflows repeatable and resilient Receive and operationalize reports stabilized by Finance Data Products, integrating them into day-to-day RTB reporting operations Reduce fire-drill, ad-hoc response patterns by replacing them with documented, recurring workflows and automation Identify and drive automation opportunities across RTB reporting processes to improve efficiency, reduce manual effort, and further reduce ad-hoc work Own primary stakeholder relationships for RTB work, serving as the go-to point of contact across teams Lead large-scale, cross-functional initiatives with significant autonomy — from problem definition through execution — proactively communicating progress and risks to stakeholders and management Proactively identify risks, gaps, and opportunities for improvement within RTB reporting and drive initiatives to address them Experience: BA/BS with 5+ years of experience in finance, accounting, business, consulting, or analytics Advanced proficiency in

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📍 Toronto, Canada· Full-time
✓ High-confidence listingCompany trend -74.4%

From C$136K/yr

Quick readStrong listing-quality and freshness signals

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Our mission depends on having a digital representation of the physical world - a map with all routing related (real-time) information. This is what makes Lyft different from many products: our products don’t just facilitate online interactions, they facilitate dynamic, real-world ones. Without mapping services, none of these real world interactions between people and transport can happen. We are hiring a Senior Software Engineer to join our Pickup, Places and Search team within the Mapping organization that is responsible for building, enhancing and maintaining the Rider and Driver product for the Pickup/Drop off Experience. This team supports the backbone of Lyft’s search system, supporting millions of rides by helping our riders and drivers connect and reach their destination. Our focus is to ensure the pickup/dropoff experience is seamless by enhancing guidance and routing as well as the rider experience. Additionally the team uses map data and other signals to create new product experiences in collaboration with teams across Lyft. This team has a history of enabling rich and creative features that directly influence the product for all of our users. We constantly innovate and incorporate cutting-edge technologies to make the lives of our community more enriched. In this role, you'll collaborate with other engineering teams, product, data science, analytics, and operations on programs that empower us to iterate quickly, delighting our passengers and drivers with rideshare focused mapping experiences. Responsibilities: Drive high-impact projects and innovate new solutions to provide the best customer experiences Lead backend and cross functional projects to achieve long term goals as well as deliver short term roadmaps Lead large features from idea to successful execution and launch Own systems and

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📍 Toronto, Canada
✓ High-confidence listingCompany trend -74.4%
Quick readStrong listing-quality and freshness signals

At Lyft, our purpose is to serve and connect, cultivating an inclusive environment where all team members can thrive. As the Business Systems Lead for Payroll & Time, you will lead Lyft's global migration onto Dayforce following recent acquisitions. Sitting within People Technology in Corporate Engineering and IT (CEIT), you'll join Lyft's Dayforce program at a formative moment: the initial rollout spans 12–15 countries over two-plus years, and you're joining early enough to directly shape how implementation, governance, and vendor management get done — not inherit a playbook someone else already wrote. You'll be backed by a mature, experienced Payroll Operations team who bring deep subject-matter expertise, while you own the technical and functional side: driving requirements, directing our systems integrator, and building the governance and vendor management model you'll run long-term as the platform's product/service owner. Sitting within People Technology in CEIT, you will drive requirements, make key functional decisions, and partner closely with Payroll Operations, HR, Legal, and Finance. You'll lead vendor delivery to ensure accurate, compliant payroll and time tracking across each migration wave, then own platform governance and vendor management long-term once the program stabilizes. We're looking for someone who can act as the translation layer between operations, executives, and technical teams — equally comfortable explaining payroll concepts to engineers and system constraints to business stakeholders. Responsibilities: Own Requirements and Direct the Implementation Partner Serve as the internal functional owner for the Dayforce payroll and time migration, driving requirements and directing the systems integrator partner. Translate payroll policy, collective bargaining terms, and statutory requirements — as defined by Payroll Operations and Legal — into actionable technical specifications. Validate vendor configurations against country-specific rule

Artificial IntelligenceFinanceHRPayroll
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📍 Toronto, Canada· Full-time
✓ High-confidence listingCompany trend -74.4%

$129K – $161.3K/yr

Quick readStrong listing-quality and freshness signals

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. We are hiring a Marketing Technology Lead to own Lyft's B2B marketing technology stack, spanning marketing automation, content and web, lead routing, data enrichment, and attribution. As the senior technical owner of that stack, you will lead solution design, own the architecture and data model that carry a lead from first touch through to a qualified opportunity, and partner with Marketing Operations, Sales Operations, Sales Technology, Privacy, Legal, and Data to translate business needs into durable, scalable systems. This is a hands-on leadership role for someone who knows B2B marketing operations, can build the systems that run them, and is looking for ways to bring AI into how the stack works, not just what it produces. Responsibilities: Serve as the senior technical owner of the B2B marketing technology stack, from solution design through delivery, adoption, and ongoing support. Lead requirements gathering with Marketing Operations, Sales Operations, Sales Technology, and Data partners, and translate them into functional and technical designs. Remain hands-on, configuring and extending the marketing automation platform (HubSpot) across workflows, forms, lead scoring, and custom objects, and building the integrations that connect the stack. Own the marketing technology roadmap and architecture, including the lead and account data model, enrichment and routing logic, and integrations with the CRM, data platform, web, and advertising systems. Own the tracking and instrumentation layer, including tag management, site and campaign tracking, and the data capture behind attribution. Own the lead lifecycle systems, partnering with Sales Operations and Sales Technology on lead identity, deduplication, scoring, routing, MQL and SQL definitions, and funnel stage integrity. Identify where AI can im

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SX
📍 Toronto, Canada· Full-time
✓ High-confidence listing

From $115K/yr

Quick readStrong listing-quality and freshness signals

ROLE: SENIOR FINANCE MANAGER LOCATION: TORONTO The Role Salt XC is looking for a Senior Finance Manager to lead the day-to-day financial management of The Kitchen, a large-scale embedded agency partnership with a Fortune 500 client. This role will be the primary Finance partner and point of contact for The Kitchen. While Salt’s broader Finance team will continue to execute transaction processing, including payroll, accounts payable, accounts receivable and expense processing, this person will sit at the centre of the operation—ensuring projects are financially controlled, billings happen on time, revenue and costs are appropriately recognized, reporting is accurate, and stakeholders have clear and timely visibility into the financial health of the business. This is an ideal role for someone with strong project accounting and revenue accounting experience who is equally comfortable working with Finance teams, agency operators, producers and senior client stakeholders. Key Responsibilities Project & Financial Management • Own the financial oversight of approximately 100-150 client projects annually • Maintain accurate project financials, including budgets, committed costs, actual costs, billings and project-level profitability • Ensure production costs and employee expenses are accurately captured and allocated to the appropriate projects • Monitor project financial activity from initiation through final reconciliation and close • Identify financial discrepancies, aging items and project risks and proactively drive them to resolution • Maintain strong financial controls while supporting the speed and flexibility required in an agency environment • Identify areas for efficiency and cost reductions Revenue, Billing & PO Management • Own the financial workflow between project teams, both internal and external, to ensure projects are billed accurately and on tim

AIExcelAccountingFinance
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📍 Toronto, Canada· Full-time
✓ High-confidence listing

From C$1.2M/yr

Quick readStrong listing-quality and freshness signals

About the Role: Tubi is seeking a highly skilled and experienced Senior QA Automation Engineer to lead quality assurance initiatives for our cutting-edge streaming and AI-driven product features. This pivotal role involves ensuring exceptional end-to-end user experiences, robust streaming playback, and the accuracy and integrity of our AI/ML features across web, mobile, and OTT platforms. We're looking for a candidate with a strong background in streaming QA and deep technical knowledge of media workflows. You'll be instrumental in collaborating with engineering, product, and data science teams to define comprehensive QA strategies that guarantee both functional excellence and data-level quality. This is a hybrid role based out of our Toronto office. You must be willing to travel to our Toronto office three days/week. What You'll Do: Design and lead test strategies for streaming workflows, playback systems, and AI-powered features. Test across platforms (web, mobile, and connected TV) to ensure functional parity and playback stability. Validate streaming performance—including ABR logic, encoding pipelines, and DRM integrations—under diverse real-world conditions. Debug with precision using tools like Charles Proxy, Chrome DevTools, ADB, and Xcode. Collaborate with data and ML teams to validate AI model updates, recommendations, and personalization accuracy. Leverage AI-assisted QA tools to enhance regression coverage, UI validation, and anomaly detection. Contribute to automation and CI/CD frameworks, driving faster, more reliable releases. Help drive a shift-left testing approach by engaging early in the software development lifecycle, partnering with product managers, engineers, and data scientists to identify quality risks, define test strategies, and ensure testability during requirements and design phases. Oversee QA deliverables for multiple concurrent releases and ensure seamless sign-off for production launches. Monitor live environments for playback or reco

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📍 Toronto, Quebec, Canada· Full-time
✓ High-confidence listingCompany trend -90.9%

From C$98.4K/yr

Quick readStrong listing-quality and freshness signals

We are looking for a Lead, Data Development, AI Platform to lead the team building and operating the technical platform behind Hootsuite's Analytics MCP. This includes routing infrastructure, orchestration services, agent infrastructure, and data pipelines that enable reliable AI-driven analysis at scale. You will set technical direction for the team, strengthen engineering practices, and translate target architecture and integration standards into secure, production-grade systems that Data Analytics & AI teams can confidently build on. This is a hands-on technical leadership role. You will stay close to the code while owning delivery outcomes, engineering quality, and the team's culture of craft and accountability. You will develop strong, well-reasoned recommendations on how the platform and orchestration architecture should evolve, seek approval at the Senior Manager and Director level, and then guide the team through disciplined execution. You will also partner closely with AI Context & Integration and AI Data Architecture to ensure the platform, context layer, semantic layer, and downstream agent workflows operate as one coherent system. WHAT YOU’LL DO: Lead the design and delivery of the orchestration layer that connects the Analytics MCP platform across its most complex surfaces, including query execution across schemas and models, federated data access between the data warehouse and external source systems, and multi-step agent workflows for cross-functional business processes. Develop clear technical recommendations for platform and orchestration architecture evolution, align those recommendations with Senior Manager and Director-level direction, and guide the team through disciplined execution within the approved architecture. Own the operational reliability, scalability, quality, and observability standards for core Analytics MCP components, including routing and agent infrastructure. Guide the team to build and operate these systems to prod

GitAgileAIGo
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📍 Toronto, Canada
✓ Quality checkedCompany trend -74.4%

At Lyft, our purpose is to serve and connect. We aim to achieve this by cultivating a work environment where all team members belong and have the opportunity to thrive. Lyft is building the next generation of intelligent agents powered by AI. We're seeking a Senior AI Agentic Engineer to lead this transformation across the enterprise. This is a strategic role for someone who can bridge the gap between AI technology and business value, designing and deploying AI-powered workflows that deliver measurable outcomes. You'll work across IT, people operations, marketing, sales, finance, legal, and procurement to architect AI-first solutions that solve complex business problems. Responsibilities: Architect and implement AI agents and intelligent workflows that transforms complex, multi-step business processes and deliver quantifiable business outcomes Partner with business leaders and stakeholders across multiple departments to identify high-impact AI opportunities that align with organizational objectives Elicit requirements from diverse stakeholders and translate complex business problems into technical solutions Build compelling business cases that clearly articulate ROI, implementation costs, benefits, timelines, and strategic alignment Evaluate, recommend, and implement AI solutions that best fit organizational needs and use cases Design solutions with an AI-first approach, ensuring optimal value delivery and user experience Monitor and measure the performance of AI workflows, using data-driven insights to demonstrate value and drive continuous improvement Design and deliver training programs, workshops, office hours, and enablement materials that help teams understand and adopt agentic solution Create frameworks, best practices, templates, and reusable patterns that accelerate AI adoption and ensure consistent quality Build a community of practice around AI and intelligent agents, empowering others to identify opportunities and contribute to the agentic roadmap Act as

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