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Hanabi Ai Inc.

Software Engineering

Posted on Sep 15, 2026

Own the full path from database design and APIs to web frontends and deployment.
Take AI products from zero to one, shipping independently across the stack.
Partner closely with product on growth experiments and data-informed iteration.

Design and develop platform web products, admin dashboards, and API services - TypeScript + Next.js on the front end, Python + MongoDB on the back end.
Independently complete the full path from database design and API development to frontend implementation and deployment.
Participate in product growth experiments, including retention, conversion, and funnel optimization.
Use data tools such as Amplitude or PostHog to propose executable growth plans.
Participate in user feedback analysis, requirement breakdown, and feature iteration.

Strong command of React and Next.js, with understanding of modern patterns such as App Router and Server Components.
Strong Python backend development skills and familiarity with ASGI async frameworks such as FastAPI or Starlette.
Familiarity with MongoDB.
Hands-on experience building LLM applications, calling multi-model APIs, and orchestrating AI workflows.
Strong TypeScript skills and the ability to maintain type consistency across frontend and backend - e.g., generating TypeScript clients from OpenAPI specs via openapi-typescript.

Experience in product operations, growth, or data analysis.
Experience building a product from zero to one.
Experience in paid acquisition, SEO, content operations, or community operations.

Send your resume along with GitHub, personal project, or technical writing links to the contact below.
For open-source contributions or past projects, direct links or short write-ups are welcome.
Take-home tasks, if any, will be paid at a reasonable market rate.
No requirements around years of experience or degree - we evaluate on technical depth and past work.