Staff Product Designer - Analytics

Weave
Full-time

📍 Job Overview

Job Title: Staff Product Designer - Analytics

Company: Weave

Location: India

Job Type: FULL_TIME

Category: Product Design / UX Design (Analytics Focus)

Date Posted: 2026-09-02

Experience Level: 7+ Years (Mid to Senior Level)

Remote Status: Fully Remote

🚀 Role Summary

  • Lead the end-to-end design of complex analytics products, focusing on translating intricate business data and reporting workflows into intuitive, actionable user experiences.

  • Drive product strategy and roadmap definition for the Analytics suite by championing a customer-centric approach, leveraging deep insights into how healthcare practices utilize data for critical business decisions.

  • Establish and scale cohesive, consistent interaction models and design patterns across the entire Analytics ecosystem, ensuring a unified and predictable user journey.

  • Collaborate closely with Product Management, Engineering, and other cross-functional stakeholders to identify user needs, frame opportunities, and deliver high-quality, impactful design solutions throughout the product lifecycle.

📝 Enhancement Note: This role is positioned as a "Staff" level designer, indicating a need for significant autonomy, strategic influence, and the ability to tackle complex, ambiguous problems. The focus on "Analytics" within a healthcare SaaS platform requires a specialized understanding of data visualization, reporting, and the unique needs of small-to-medium businesses. The remote nature within India necessitates strong asynchronous communication skills and collaboration across time zones.

📈 Primary Responsibilities

  • Spearhead the complete design lifecycle for Weave's Analytics product, transforming sophisticated data, reporting capabilities, and business workflows into user-friendly, actionable experiences across dashboards, reports, and core product interfaces.

  • Act as a key partner to Product and Engineering teams, actively participating in problem definition, opportunity discovery, and the translation of complex customer and business requirements into clear, effective design solutions that drive measurable outcomes.

  • Significantly influence the vision, strategy, and roadmap for the Analytics product by contributing a robust customer perspective, employing systems thinking, and demonstrating a profound understanding of how healthcare practices leverage data for strategic business decisions.

  • Develop and implement scalable interaction models and design patterns that effectively balance usability, discoverability, flexibility, and depth within various Analytics workflows.

  • Cultivate a unified and cohesive user experience across the entire Analytics suite by mitigating fragmentation and establishing consistent mental models for users interacting with dashboards, filters, reports, visualizations, and comparative analysis tools.

  • Utilize and extend Weave’s Design System to foster scalable, accessible, and consistent user experiences, while proactively introducing new patterns that accommodate evolving data and reporting requirements.

  • Conduct and synthesize user research with practice owners, office managers, and front-office staff to gain deep insights into how customers interpret and act upon data, identifying opportunities to enhance the insightfulness and actionability of the Analytics product.

  • Employ product analytics, customer feedback mechanisms, and tools such as Pendo and Sigma to rigorously evaluate the effectiveness of designs, pinpoint areas of friction, and drive continuous improvement based on observed user behavior.

  • Champion a high standard for design quality within the team and across the organization, contributing to the broader design practice through active participation in critiques, strategic design discussions, knowledge sharing initiatives, and mentorship of other designers.

  • Maintain close collaboration with the Engineering team throughout the implementation phase to ensure the fidelity of design intent, interaction quality, accessibility standards, and overall system cohesion are preserved through to product delivery.

  • Apply a systems-level perspective to the Analytics product, focusing on simplifying complex workflows, establishing reusable design patterns, and building a scalable architectural foundation for future product evolution.

📝 Enhancement Note: The responsibilities emphasize a senior-level contribution, requiring not just execution but also strategic input, influencing product direction, and establishing design standards. The focus on "data-intensive products," "complex data," and "systems thinking" points to the need for a designer experienced in handling large datasets and interconnected features.

🎓 Skills & Qualifications

Education: Bachelor's degree in Design, Human-Computer Interaction, Computer Science, or a related field, or equivalent practical experience.

Experience: 7+ years of dedicated product or UX design experience, with a demonstrated history of successfully launching and iterating on data-intensive products within domains such as analytics, business intelligence (BI), SaaS platforms, financial services, or healthcare.

Required Skills:

  • Demonstrated expertise in end-to-end product design, from initial problem discovery and user research through strategy formulation, ideation, high-fidelity prototyping, and iterative post-launch improvements.

  • Proficiency in designing data-dense interfaces, including sophisticated dashboards, comprehensive reporting tools, interactive data visualizations, advanced filtering and segmentation capabilities, drill-down functionalities, and comparative analysis workflows.

  • Strong command of UX and visual design principles, with the ability to translate complex data structures, intricate workflows, and challenging information architectures into intuitive, scalable, and actionable user experiences.

  • Proven product design thinking skills, with the capacity to independently identify critical problems, frame strategic opportunities, influence product direction, and make well-reasoned design decisions in close partnership with Product Management and Engineering.

  • Hands-on, practical experience with industry-standard design and prototyping tools, specifically Figma, for creating wireframes, high-fidelity mockups, and interactive prototypes.

  • Experience with various user research methodologies, including qualitative interviews, usability testing, and surveys, to gather actionable insights and validate design decisions.

  • Proficiency in utilizing product analytics tools (e.g., Pendo, Sigma, Maze, Amplitude, Mixpanel) to understand user behavior, identify friction points, and inform design iterations.

  • Exceptional communication, collaboration, and stakeholder management abilities, with a proven capacity to build consensus and drive alignment across diverse, cross-functional teams.

  • A balanced approach to decision-making, adeptly considering customer needs, business objectives, technical feasibility, and long-term scalability.

  • Meticulous attention to detail and a high standard for design craft, with a consistent focus on usability, accessibility, consistency, and overall quality across the entire user experience. Preferred Skills:

  • Experience designing for multi-tenant SaaS products and navigating the complexities of legacy systems and integrations.

  • Familiarity with or experience in the healthcare industry, particularly with the operational workflows and data needs of small-to-medium practices.

  • Knowledge of design systems, including their creation, maintenance, and application to ensure consistency and scalability.

  • Experience mentoring junior designers and contributing to the development of a design team's capabilities and standards.

  • Understanding of agile development methodologies and experience working effectively within agile product development cycles.

📝 Enhancement Note: The "Staff" designation and the specific requirements for data-intensive products and analytics workflows imply a need for deep expertise beyond basic UI design. The emphasis on Figma, Pendo, and Sigma points to a modern tech stack for design and product analytics. The requirement for 7+ years of experience reinforces the senior nature of this role.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

  • Demonstrate a strong portfolio showcasing end-to-end product design projects, with a significant emphasis on analytics, data visualization, and complex information architecture.

  • Include detailed case studies that highlight your process for problem discovery, user research synthesis, strategic design decisions, and iterative refinement based on data and feedback.

  • Present specific examples of how you have translated complex data and business requirements into intuitive, actionable user interfaces and workflows.

  • Showcase your ability to design for scalability, consistency, and usability within data-intensive product environments.

  • If applicable, provide examples of contributions to or utilization of design systems. Process Documentation:

  • Clearly articulate your design process, detailing how you approach problem definition, user research, ideation, prototyping, user testing, and collaboration with product and engineering.

  • Illustrate your methods for incorporating user feedback and product analytics (e.g., Pendo, Sigma) into iterative design improvements.

  • Document your approach to establishing and maintaining design consistency and scalability, especially within complex product ecosystems like analytics platforms.

  • Show how you ensure accessibility standards are met and integrated throughout the design and development lifecycle.

📝 Enhancement Note: For a Staff Product Designer role, especially one focused on analytics, the portfolio must go beyond visual polish. It needs to demonstrate strategic thinking, problem-solving skills related to complex data, and a robust, data-informed design process. Case studies should clearly articulate the "why" behind design decisions and the measurable impact.

💵 Compensation & Benefits

Salary Range: Given the role's seniority (Staff level), extensive experience requirements (7+ years), and the fully remote nature within India, a competitive salary range is expected. Based on industry benchmarks for senior product designers in India specializing in SaaS and analytics, the estimated annual salary range would be approximately ₹2,000,000 to ₹3,500,000 (INR). This range can vary based on the candidate's specific experience, skill set, and negotiation.

Benefits:

  • Comprehensive health insurance coverage (medical, dental, vision) for employees and potentially dependents.

  • Generous paid time off (PTO) policy, including vacation days, sick leave, and public holidays.

  • Retirement savings plan or provident fund contributions, in line with Indian regulations.

  • Opportunities for professional development, including access to training, conferences, and online learning platforms.

  • Home office setup stipend or reimbursement to ensure a productive remote work environment.

  • Potential for performance-based bonuses or stock options, depending on company policy.

  • Employee Assistance Program (EAP) providing confidential counseling and support services.

  • Regular virtual team-building activities and social events to foster connection among remote employees.

Working Hours: Standard full-time engagement, typically around 40 hours per week. Flexibility may be offered, with core working hours designed to facilitate collaboration across different time zones, particularly with teams in other regions. Asynchronous communication tools and practices will be crucial.

📝 Enhancement Note: The salary estimate is based on research for senior/staff-level Product Designers in India with significant experience in SaaS and analytics. Compensation in tech roles in India can vary widely by city and company, but this range reflects a competitive offering for a well-established company like Weave hiring for a critical senior role. Benefits are standard for established tech companies, adapted for a remote-first model in India.

🎯 Team & Company Context

🏢 Company Culture

Industry: Software / Technology - specifically focused on Healthcare Communications and Engagement Platforms for small-to-medium businesses (SMBs).

Company Size: Weave is a growing company, likely in the mid-to-large size range within the tech sector, indicated by its established presence and product offerings.

Founded: Weave was founded in 2011, giving it over a decade of experience in the market, suggesting a stable yet innovative company culture.

Team Structure:

  • The Product Design team is likely structured to support various product areas. This role reports to a Product Design Manager, indicating a clear reporting line and management support.

  • Designers are expected to collaborate closely with Product Managers and Engineering teams, forming cross-functional "squads" or "pods" focused on specific product domains like Analytics.

  • The company fosters a culture of collaboration across disciplines and potentially across different geographic locations, emphasizing the importance of effective remote teamwork. Methodology:

  • Weave emphasizes a customer-centric approach, using research and data to inform product decisions. This involves understanding the day-to-day realities of their target customers (healthcare practices).

  • Agile development methodologies are likely employed, requiring designers to work iteratively and adapt to changing requirements.

  • The company values designers who can bring clarity to ambiguity, demonstrate strategic thinking, and advocate for user needs while balancing business and technical constraints.

Company Website: https://www.getweave.com/

📝 Enhancement Note: The company's focus on healthcare SMBs means the Analytics product is designed for users who may not be data scientists but need actionable insights to run their practice. This context is crucial for understanding the design challenges and user needs. The founding date suggests a company that has moved beyond the startup phase and likely has mature processes.

📈 Career & Growth Analysis

Operations Career Level: This role is at the "Staff" level, signifying a senior individual contributor with significant autonomy and influence. It's beyond a typical senior designer role, implying expectations for leadership in design strategy, mentorship, and tackling the most complex product challenges. The focus is on deep expertise within the Analytics domain and its impact on the broader platform.

Reporting Structure: The Staff Product Designer will report directly to the Product Design Manager. This manager is likely responsible for the overall design vision, team performance, and career development of their direct reports. Close collaboration will be essential with Product Managers and Engineering Leads within the Analytics product area.

Operations Impact: The Staff Product Designer's impact will be measured by their ability to transform raw business data into clear, actionable insights that directly influence the success of Weave's SMB healthcare clients. This includes improving customer retention, driving product adoption, and enabling clients to make better business decisions, thereby enhancing Weave's value proposition and market position. The designer will play a critical role in shaping the future direction and user experience of a core product suite.

Growth Opportunities:

  • Deep Specialization: Opportunity to become a recognized expert in designing analytics and data visualization solutions within the healthcare SaaS domain, potentially leading to Principal or Lead Designer roles focused on data products.

  • Strategic Influence: Grow influence over product strategy and roadmap for the Analytics domain, shaping the future direction of a critical product area for Weave.

  • Mentorship & Leadership: Develop leadership skills by mentoring junior designers, contributing to design critiques, and establishing best practices for data-driven design within the company.

  • Cross-functional Impact: Expand influence by collaborating on broader platform design initiatives, contributing to the overall coherence and quality of the Weave product suite.

  • Industry Recognition: Potential to contribute to industry thought leadership through speaking engagements or publications related to designing for healthcare analytics.

📝 Enhancement Note: The "Staff" designation implies a career path that emphasizes deep expertise and influence rather than people management, although mentorship is expected. The growth opportunities are geared towards increasing strategic impact and subject matter mastery within the company and potentially the industry.

🌐 Work Environment

Office Type: This is a fully remote position within India. While there isn't a physical office requirement for this role, Weave likely maintains corporate offices elsewhere, which may be used for occasional in-person meetings or company events if feasible for remote employees.

Office Location(s): The role is remote within India. Weave's headquarters are in Lehi, Utah, USA, and they have additional offices in the US. The remote nature for this role specifically targets talent in India, implying a distributed team structure.

Workspace Context:

  • The remote work environment necessitates a high degree of self-discipline, proactive communication, and effective use of collaboration tools to maintain team cohesion and productivity.

  • Designers will have access to digital tools and platforms required for design, research, and communication. The company may provide a stipend for home office setup to ensure an optimal working environment.

  • Opportunities for interaction will be primarily through virtual channels, including video conferencing, instant messaging, and project management software. Regular virtual meetings with the Product Design Manager, Product Managers, and Engineering teams are expected.

Work Schedule: While the role is full-time (approx. 40 hours/week), the remote nature and potential global team structure means there will be a need for flexibility. Core hours will likely be established to facilitate synchronous collaboration with teams in different time zones. Asynchronous communication and documentation will be key to bridging time differences.

📝 Enhancement Note: The fully remote aspect for a role based in India requires a strong emphasis on asynchronous communication protocols and tools. The company's US-based headquarters mean collaboration might involve significant time zone differences, making clear documentation and proactive updates essential.

📄 Application & Portfolio Review Process

Interview Process:

  • Initial Application & Screening: Review of resume and portfolio for alignment with required experience and skills, particularly in data-intensive design and analytics.

  • Hiring Manager Interview: Discussion with the Product Design Manager to assess overall fit, design philosophy, strategic thinking, and alignment with company values. This stage will likely delve into past projects and career aspirations.

  • Design Challenge/Portfolio Review: A more in-depth session, potentially involving presenting a case study from your portfolio. This could include a live critique or a prepared presentation focusing on a complex analytics design problem you've solved, demonstrating your process, decision-making, and impact. Expect questions about how you handle ambiguity and complex data.

  • Cross-functional Interviews: Meetings with Product Managers and Engineering Leads from the Analytics team. These interviews will focus on your ability to collaborate, communicate technical concepts, understand business needs, and work effectively within an agile development environment.

  • Final Interview/Executive Review: Potentially a final conversation with a senior leader or executive to assess strategic alignment and overall impact potential.

Portfolio Review Tips:

  • Curate Selectively: Choose 3-4 of your strongest projects that best showcase your experience with analytics, data visualization, and complex SaaS products. Tailor your selection to highlight experience relevant to Weave's customer base (healthcare SMBs) if possible.

  • Tell a Story: For each case study, clearly articulate the problem, your role, the process you followed, the key decisions you made (and why), the challenges you encountered, and the measurable outcomes or impact of your work. Use visuals effectively to illustrate your points.

  • Highlight Process & Rationale: Emphasize your thought process, how you synthesized research, how you approached information architecture, and why you chose specific design solutions. Demonstrate your systems thinking and ability to create scalable patterns.

  • Showcase Data Expertise: Clearly illustrate how you've designed for data density, reporting, and visualization. Explain how your designs help users derive insights and take action.

  • Prepare for Questions: Be ready to discuss your design rationale, how you handle feedback, collaborate with stakeholders, and navigate technical constraints.

Challenge Preparation:

  • Understand the Domain: Familiarize yourself with the healthcare SMB market and the types of data and insights they rely on to manage their practices. Research Weave's current Analytics product and competitors.

  • Practice Articulation: Rehearse explaining complex design decisions and processes concisely and compellingly. Practice presenting your portfolio case studies.

  • Anticipate Analytics Problems: Consider common challenges in designing for analytics: data accuracy, user interpretation, dashboard overload, actionable insights vs. raw data, and diverse user needs within a single platform.

  • Focus on Collaboration: Prepare examples of how you have successfully partnered with Product Managers and Engineers, managed stakeholder expectations, and driven consensus.

📝 Enhancement Note: The interview process suggests a thorough evaluation of design craft, strategic thinking, and collaborative capabilities. The portfolio review is critical and should focus on demonstrating expertise in data-intensive design and a mature, data-informed design process.

🛠 Tools & Technology Stack

Primary Tools:

  • Design & Prototyping: Figma (Primary tool for wireframing, high-fidelity mockups, and interactive prototyping). Candidates are expected to be highly proficient.

  • Design System: Experience leveraging and contributing to design systems for consistency and scalability.

  • User Research: Proficiency in conducting and synthesizing qualitative user research (interviews, usability testing) and leveraging user feedback.

  • Product Analytics: Hands-on experience with tools like Pendo, Sigma, Maze, Amplitude, or similar platforms for understanding user behavior, tracking feature adoption, and identifying friction points.

Analytics & Reporting:

  • Data Visualization Tools: Experience designing effective data visualizations, dashboards, and reporting interfaces. Understanding of principles for clear and actionable data presentation.

  • BI/Analytics Platforms: Familiarity with the landscape of business intelligence and analytics platforms, even if not directly using them for design.

CRM & Automation:

  • While not explicitly stated as a primary design tool, understanding how analytics integrate with CRM and other business systems is beneficial for context.

📝 Enhancement Note: The explicit mention of Figma, Pendo, and Sigma indicates the core tools candidates should be familiar with. The role requires a designer who can not only create beautiful interfaces but also understand and leverage data to inform design decisions and measure impact.

👥 Team Culture & Values

Operations Values:

  • Customer Obsession: A deep commitment to understanding and serving the needs of small-to-medium healthcare practices, designing solutions that genuinely improve their operations and patient care.

  • Clarity in Ambiguity: The ability to take complex problems, particularly those involving intricate data and workflows, and distill them into clear, understandable, and actionable user experiences.

  • Systems Thinking: A focus on designing holistically, considering how individual components of the Analytics product fit into the larger platform and contribute to a cohesive user journey.

  • Data-Driven Impact: Valuing the use of data, both for user insights and for measuring the success of design solutions, to drive continuous improvement and demonstrate tangible business value.

  • Ownership & Proactivity: Taking initiative, driving projects forward independently, and holding oneself accountable for delivering high-quality outcomes.

  • Collaboration & Trust: Building strong, trusting relationships with Product, Engineering, and other cross-functional partners to achieve shared goals.

Collaboration Style:

  • Cross-functional Partnership: A highly collaborative approach, working hand-in-hand with Product Managers to define strategy and Engineers to ensure seamless implementation.

  • Design Critiques & Feedback: An open culture for giving and receiving constructive feedback through design critiques to elevate the quality of work.

  • Knowledge Sharing: A willingness to share learnings, best practices, and insights across the design team and with other departments to foster collective growth.

  • Remote-First Communication: Proficiency in asynchronous communication methods, clear documentation, and effective use of virtual collaboration tools to bridge geographical distances.

📝 Enhancement Note: The company's stated values like "stay hungry, care more, stay curious" and the emphasis on understanding the "day-to-day reality of healthcare practices" highlight a culture that values empathy, continuous learning, and practical problem-solving.

⚡ Challenges & Growth Opportunities

Challenges:

  • Data Complexity: Designing intuitive experiences for highly complex and potentially large datasets, ensuring users can easily find, interpret, and act on critical business information.

  • User Segmentation: Catering to a diverse user base within healthcare practices (e.g., front office staff, practice managers, owners) who have varying levels of data literacy and business needs.

  • Scalability & Consistency: Establishing scalable design patterns and maintaining consistency across a broad analytics suite that is continuously evolving, while also integrating with a larger product platform.

  • Balancing Power & Simplicity: Creating analytics tools that are both powerful enough to meet sophisticated business needs and simple enough for SMB users to adopt and utilize effectively.

  • Remote Collaboration: Effectively collaborating with cross-functional teams across different time zones, requiring strong asynchronous communication and proactive engagement.

Learning & Development Opportunities:

  • Deep Dive into Healthcare Analytics: Gaining specialized knowledge in the unique data and operational challenges faced by healthcare SMBs, becoming an expert in this niche.

  • Advanced Data Visualization Techniques: Exploring and implementing cutting-edge data visualization patterns and best practices for complex datasets.

  • Design System Evolution: Contributing significantly to the expansion and refinement of Weave's Design System, particularly for data-centric components.

  • Mentorship & Influence: Developing leadership capabilities by mentoring junior designers and influencing product strategy at a senior level.

  • Industry Best Practices: Staying abreast of emerging trends in product analytics, BI tools, and UX design for data-intensive applications.

📝 Enhancement Note: The challenges highlight the core complexities of the role, particularly around data and user needs in a specific industry context. The growth opportunities are well-aligned with a Staff-level designer's progression, focusing on deepening expertise and increasing strategic influence.

💡 Interview Preparation

Strategy Questions:

  • "Describe a time you led the design of a complex data-intensive product. What was the problem, your process, and the outcome?" (Focus on your approach to ambiguity, data synthesis, and user impact.)

  • "How would you approach designing a new dashboard for healthcare practice owners to track key performance indicators (KPIs) related to patient acquisition and retention?" (Demonstrate your understanding of user needs, data, and actionable insights.)

  • "Walk us through your process for establishing or contributing to a design system, especially for data visualization components. How do you ensure scalability and consistency?" (Highlight your systems thinking and attention to detail.)

  • "How do you balance the needs of different user segments (e.g., practice managers vs. front-office staff) when designing analytics tools?" (Showcase your user empathy and ability to cater to diverse needs.) Company & Culture Questions:

  • "What interests you about Weave and our mission to serve healthcare practices?" (Research Weave's mission, values, and products.)

  • "How do you approach collaborating with Product Managers and Engineers, especially in a remote, cross-functional environment?" (Be prepared to share examples of successful partnerships and conflict resolution.)

  • "Describe a situation where you had to influence product strategy with your design insights. How did you build alignment?" (Demonstrate your strategic thinking and communication skills.)

  • "How do you stay current with trends in UX design, data visualization, and analytics?" (Show your commitment to continuous learning.) Portfolio Presentation Strategy:

  • Structure is Key: For your chosen case study, clearly outline the problem statement, your role and responsibilities, the research conducted, your design process (sketches, wireframes, prototypes, user testing), key design decisions and rationale, challenges faced, and the final outcome/impact.

  • Quantify Impact: Whenever possible, use metrics to demonstrate the success of your designs (e.g., increased user engagement, improved task completion rates, positive customer feedback).

  • Show, Don't Just Tell: Use visuals effectively to showcase your work at different stages of the design process. Explain your design choices clearly and concisely.

  • Focus on Data & Systems: Emphasize how you handled complex data, designed for clarity, and contributed to a scalable system. Discuss your understanding of information architecture and interaction design for data-rich environments.

  • Be Prepared for Deep Dives: Expect detailed questions about your process, rationale, and how you would tackle specific challenges within Weave's product.

📝 Enhancement Note: The interview preparation focuses on demonstrating core competencies for a Staff Designer: strategic thinking, deep domain knowledge (analytics, healthcare), strong process, and excellent collaboration skills. The portfolio is the primary vehicle for showcasing these abilities.

📌 Application Steps

To apply for this Staff Product Designer - Analytics position:

  • Submit your application through the provided link on Ashby, ensuring your resume and portfolio are up-to-date and tailored to the role's requirements.

  • Curate Your Portfolio: Select 3-4 of your most impactful projects, prioritizing those that demonstrate expertise in designing complex analytics, data visualization, and SaaS products. Ensure each project clearly outlines the problem, your process, your specific contributions, and measurable outcomes.

  • Optimize Your Resume: Highlight your 7+ years of relevant experience, emphasizing skills in product design, UX design, data-intensive products, Figma, user research, and collaboration. Use keywords from the job description naturally.

  • Prepare Your Pitch: Practice articulating your design philosophy, your approach to tackling complex data problems, and your experience with tools like Figma and product analytics platforms. Be ready to present a detailed case study from your portfolio.

  • Research Weave: Familiarize yourself with Weave's mission, target market (healthcare SMBs), product offerings, and company culture. Understand how their analytics product supports their overall mission.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.

Application Requirements

Requires 7+ years of product or UX design experience with a focus on data-intensive products and SaaS platforms. Candidates must possess strong visual design fundamentals, proficiency in Figma, and the ability to synthesize research into clear, scalable design solutions.