Fullstack/Backend Developer (API & AI Integration specialist)

Vessel is hiring a Fullstack/Backend Developer to help build the AI-powered fundraising and investor relations platform trusted by some of the world’s most renowned venture capital and private equity firms. Small team. Senior engineers. Real product impact. Our stack includes: Node.js • SvelteKit • Twirp/Protobuf • Postgres/Kysely • Docker • Cloudflare • AWS • Nix • OpenAI/Claude.

About Vessel

Vessel is building the AI-powered platform redefining how capital is raised globally. Today, leading venture capital and private equity firms rely on Vessel to run digital closings, unlock investor insights, and deliver a modern investor experience.

We exist to make private markets more transparent, more efficient, and more human.

Vessel has already helped fund managers secure hundreds of millions of dollars through our platform — a strong signal of the industry’s appetite for a better way to raise and manage capital. We are backed by leading venture capital firms, including Inovia Capital, Afore Capital, FJ Labs, BYVP, and Golden Ventures. And we’re just getting started, with an ambitious roadmap ahead of us.

We’re a small, senior team shipping fast across a modern stack:

• Monorepo: pnpm + Turborepo
• Backend: Node.js (TypeScript) microservices
• Frontend: SvelteKit web apps
• API: Twirp RPC + Protobuf (strongly-typed contracts, fast iteration)
• Database: Postgres + Kysely (type-safe SQL, zero ORMs)
• Infra: Docker, Cloudflare, AWS, Nix-driven DX
• AI: OpenAI + Claude for summarization, categorization and insight generation

We’re building features like the AI-powered IR Assistant, automatic PDF parsing/categorization, and LLM-enhanced investor insights. You’ll work directly on these capabilities, shaping how fund managers use AI to understand and communicate with LPs.

At Vessel, developers have real product influence, deep technical ownership, and the chance to build the future of private markets from the ground up.

What You’ll Do

• Design and implement new API endpoints and services using Node.js, TypeScript, and Twirp RPC
• Collaborate with product and frontend teams to build AI-powered investor workflows (LLM summarization, insights, categorization)
• Extend and maintain internal packages (e.g., RPC, utils) across the monorepo
• Design and maintain relational database structures. Optimize queries. etc.
• Write and maintain robust unit and integration tests
• Contribute to performance and scalability improvements in our API services
• Experiment with AI models and API integrations to unlock new product capabilities

You’ll Thrive Here If You

• Have 5+ years of industry experience with a focus on backend and some knowledge of Node.js/TypeScript
• Enjoy building clean, modular APIs with a focus on reliability and type safety
• Are comfortable with relational databases (especially Postgres)
• Have worked in monorepo environments (pnpm, Turborepo, or similar)
• Are curious about AI/LLM development — and eager to apply it in production settings
• Appreciate working in a small, fast-moving, async-first team
• Value code quality, testing, and product impact equally

Nice to Have

• Experience with protobuf/Twirp or gRPC
• Prior work integrating LLMs (OpenAI, Claude, etc.) into backend systems
• Familiarity with SvelteKit or modern frontend frameworks
• Contributions to open-source TypeScript projects
• Understanding of fund management, fintech, or investor platforms

What You’ll Get

We believe in transparent and competitive compensation. Salary for this role ranges from $100,000 to $160,000, based on the potential value you bring — not just the number of years on your résumé. You’ll also receive early-stage equity, so as Vessel grows, you grow with it.

Our health and dental coverage plan is generous and above market. You’ll get 20 days of paid vacation and 5 paid sick days. Additionally, everyone gets a full paid week (sometimes more!) between Christmas and New Year while the whole office is closed — no emails, no Slack.

The role is hybrid in our Mile End office: 3 days a week on-site to collaborate and build strong relationships. For 60 days per year, you can work from wherever you do your best thinking, as long as your schedule overlaps 4 hours with ET.

We also believe in building culture and connection beyond the day-to-day, so you’ll get:

• Competitive salary + meaningful equity

• Annual offsites with the global team

• A seat at the table shaping the future of private markets with leading VC and PE firms

• Autonomy, ownership, and the opportunity to do the best work of your career

What to expect

To apply to the role, you’ll need a résumé that helps us gauge your suitability. If you don’t have formal experience, showcase your skills and potential in writing — tell us about something you’ve built, something relevant to the work we do, or something that excites you. You don’t need a fancy job history.

After we review your application, you will either be invited to a virtual interview or notified via email that we will not be proceeding. Please give us a few days to get back to you.

We aim to make the interview process as quick and painless as possible, and encourage everyone to apply if they think they’re ready to do some of the best work of their careers.

Vessel looks forward to hearing from you!