Platform Developer Jobs in California

The Stockholm Environment Institute (SEI) seeks an outstanding software developer/scientist to contribute to the continued development of WEAP (Water Evaluation and Adaptation Planning), one of the world's leading platforms for integrated water resources planning and decision support. WEAP is used by governments, utilities, researchers, NGOs, and international organizations worldwide — including the California Department of Water Resources — to address drought resilience, climate adaptation, groundwater management, infrastructure planning, agricultural water use, and ecosystem sustainability.

The position combines advanced software engineering with scientific inquiry and close collaboration with researchers, modelers, and practitioners. The successful candidate will work closely with WEAP's lead developer and senior WEAP modelers and, operating with significant autonomy, translate scientific and policy needs into robust software for a global user community. They will help advance the integration of AI capabilities within WEAP, including AI-assisted workflows that support users in building, debugging, documenting, and analyzing models.

The SEI-US Center has three offices: Somerville, MA, Davis, CA, and Seattle, WA; you will be joining our twelve-person team based primarily in Davis, CA. The job location is in Davis, California.

Key Responsibilities

• Co-Lead the full development lifecycle of the WEAP software platform, architecture, design, implementation, testing, documentation, and release, including modeling tools, user interfaces, APIs, data processing workflows, and analytical functions.
• Develop and evaluate AI-assisted functionality that helps users construct, troubleshoot, document, interpret, and analyze WEAP models.
• Collaborate with researchers and modelers to translate scientific and policy needs into robust software solutions, including for cutting-edge water planning applications in California and other water-stressed regions.
• Guide and/or support integration of hydrologic, climate, economic, geospatial, and environmental datasets into modeling workflows, including approaches that help users in data-scarce environments.
• Support, cultivate and grow the international WEAP user community through technical engagement and collaborative problem solving.
• Lead the security, integrity, and responsible stewardship of WEAP software and digital assets, including applying secure software-development practices, identifying and addressing vulnerabilities, managing access and dependencies, and conducting appropriate due diligence when adopting new technologies, libraries, AI tools, or third-party services.
• Communicate technical concepts clearly to technical and non-technical audiences.
Maintain and evolve the WEAP website and online user resources, including supporting the platform’s transition to cloud-based services.

Requirements

Required Skills and Abilities:

• Excellent software engineering and programming skills, including experience developing and maintaining substantial, long-lived codebases.
• End-to-end desktop application development from architecture and UI design through implementation, testing, documentation, and release, with demonstrated use of good design principles.
• Ability, wisdom and interest in applying AI-assisted development tools and workflows, both in the development process and in scientific software features.
• Excellent analytical and problem-solving skills; creativity in reaching results in new ways.
• Ability to anticipate and address risks related to software architecture, data handling, access controls, third-party dependencies, licensing, and the appropriate protection and distribution of source code and other digital assets.
• Excellent verbal and written communication skills, with the ability to work effectively with both technical experts and non-technical stakeholders.
• Strong organizational and time management skills; proven ability to manage multiple priorities and meet deadlines. Ability to work effectively in interdisciplinary teams and international environments.
• Interest in sustainability, water resources, and environmental systems.

Preferred Technical Qualifications:

• Highly preferred: Delphi/Object Pascal, or strong experience with compiled, statically typed languages (e.g., C#, C++) and demonstrated ability to become productive in new languages; native Windows application development; scientific or numerical computing; AI-assisted software development tools and workflows.
• Also valuable: GIS and geospatial data processing; APIs and cloud-based workflows; data engineering and visualization; environmental, hydrologic, or systems modeling platforms; experience contributing to or using integrated water resources models or decision support tools.

Education and Experience

• Required: A computer science degree with 5+ years of relevant professional experience in software development, scientific computing, or modeling systems.
• Preferred: Expertise or strong interest in water resources or environmental systems; experience supporting external users or technical communities; experience in interdisciplinary or international settings; prior experience with numerical models, hydrological simulation, or integrated assessment tools.

SEI US values the wide variety of backgrounds and experiences of our research staff, and key elements in the consideration of qualified candidates include excellence; diversity of talents, backgrounds, and viewpoints; and a good fit with the institute’s mission, values, and goals.

Compensation, Location, Travel and Other Criteria

This is a full-time position at 40 hours per week. Compensation is determined by experience with a range of $90,000 to $135,000 per year.

Initially, the position will require on-site presence in the Davis, CA office at least four days per week for training and onboarding. Once that is complete, the work schedule can transition to fewer days per week in the office.

Occasional domestic and international travel.

Start Date: January 4, 2027

Application deadline: Applications are considered on a rolling basis until the position is filled.

You must either be a U.S. Citizen or Green Card (Permanent Resident Card) holder.

Applications should be written in English, and any materials generated with the assistance of AI should be clearly indicated.

No phone calls please.

Benefits

SEI offers a comprehensive benefits package, including health, dental, vision, a 5% retirement match, and paid parental and family medical leave after one year of employment.

We have a welcoming work environment with flexible work schedules, and offer 10 holidays, 20 days of vacation, and 10 days of sick leave each year to start.

Your benefits are adjusted according to your FTE (full-time equivalency.)

SEI reimburses up to $5,000 of moving expenses.

About SEI

SEI is an international not-for-profit research organization that has been engaged in environment and development issues at local, national, regional, and global levels since 1989. Our mission is to enable sustainable development by bridging science and policy and conducting integrated analysis that supports decision-makers. SEI works on cutting edge topics including climate change mitigation and adaptation, renewable energy, integrated energy and water resource modeling, short-lived climate pollutants, environmental governance, and sustainable production and consumption.

SEI’s approach is highly collaborative: stakeholder involvement is at the heart of our efforts to build capacity, strengthen institutions, and equip partners for the long term. We make sure our knowledge and findings are clearly communicated and accessible to decision-makers and civil society. We publish our own open access material in leading academic journals, and repackage our research to offer effective decision support. To promote debate and share knowledge, we convene decision-makers, academics, and practitioners, and we engage with policy processes, development action, and business practice throughout the world.

SEI is headquartered in Stockholm, Sweden, with additional centers in the United States, Colombia, Estonia, Kenya, Thailand, and the United Kingdom. Our US Center is a research affiliate of Tufts University; its main office is on the Tufts campus in Somerville, Massachusetts, and it maintains additional offices in Davis, California, and Seattle, Washington.

SEI US is an equal opportunity employer. We value diversity and an inclusive work culture. We do not discriminate on the basis of actual or perceived race, creed, color, religion, alienage or national origin, ancestry, citizenship status, age, physical or mental disability, medical condition, sex, gender (including pregnancy, childbirth, medical conditions related to pregnancy and childbirth, breastfeeding, or reproductive health decision-making), marital status, military or veteran status, sexual orientation, gender identity or expression, genetic information, past or present status as a workers’ compensation or whistleblower claimant, use of a service animal, or any other characteristic protected by applicable federal, state or local laws. We are dedicated to this policy with respect to recruitment, hiring, placement, promotion, transfer, training, compensation, benefits, employee activities and general treatment during employment. This policy and the law prohibit employment discrimination against any employee or applicant on the basis of any legally protected status outlined above.