Full-Stack Engineer Needed: Next.js 15, Convex, Blaxel & AI-SDK + Agents (like Bolt.new)
Location: []
Project Overview: We are building a high-performance AI coding agent platform (similar to Bolt.new or Lovable) that allows users to generate, run, and deploy full-stack web applications in the browser on sandboxes powered by our OpenCode based agent served via ai-sdk. Current State: The application is in a transition phase. We are migrating from a legacy architecture (Prisma/Postgres + Client-side WebContainers) to a robust, scalable architecture using Convex (Realtime DB) and Blaxel (Server-side Sandboxes with REST api). We need a Senior Developer to finalize this migration, unify the data layer, and stabilize the AI agent’s execution environment. The codebase is modern (Next.js 15, React 19, Tailwind v4) but requires an expert hand to resolve split-brain state management and finish the infrastructure integration. The Tech Stack Framework: Next.js 15.4 (App Router, Turbopack) Language: TypeScript (Strict) Database & Realtime: Convex (Primary), Prisma/Postgres (Legacy/To-be-removed) AI Orchestration: Vercel AI SDK (streamText, tool calling), OpenAI/Anthropic models via Vercel gateway - base off of the OpenCode agent Execution Environment: Blaxel (Serverless GPU/CPU Sandboxes with persistent volumes) Styling: Tailwind CSS v4, CossUi, Lucide React Auth & Payments: Clerk, Stripe Key Responsibilities Database Unification (Prisma → Convex): The codebase currently reads from both Prisma (via tRPC) and Convex. You must migrate remaining tRPC procedures (subscriptions, project management) to Convex Queries/Mutations and remove the Prisma dependency. Sandbox Orchestration (Blaxel): Solidify the BlaxelSandboxService. Ensure robust bi-directional file syncing between the Sandbox filesystem and the Convex database. Make sure that the 502 error we currently get subsides. We must have Sandboxes boot within 5s (Vercel Timeouts), and make sure that there is full persistence. Meaning if I build something 3 months ago, we keep the Volume on Blaxel, and if I boot it, it should boot in under 5 seconds, to the exact same state with the dev server running. Also, use react-idle-timer on the front-end to make sure that after 3 mins of inactivity, we can turn off the sandbox to save costs. Handle edge cases in src/ai/tools/create-sandbox.ts to ensure volumes are correctly mounted and persisted across sessions. AI Tooling Stability: Refactor AI tools (generateFiles, runCommand, applyCodeEdit) to handle failures gracefully. We must bind all tools to all the methods we have (Blaxel provides really powerful ones: https://docs.blaxel.ai/api-reference/compute/list-sandboxes) to a tool the agent can use. Reference OpenCode's GitHub (MIT) to use styles it has and what makes it so powerful. We must be on Par with Claude Code - but fully web based! Ensure the streamText response correctly updates the UI state via Convex subscriptions, replacing the legacy useProjectChat local state hacks. Frontend Refactoring: Fix hydration mismatches in components like integrations-tab.tsx and model-selector.tsx. Clean up “God components” like project-view.tsx which currently mix tRPC and Convex hooks. Cleanup: Remove legacy WebContainer code and dependencies once the Server-side Sandbox implementation is stable. Cleanup entire codebase too, and organize file structure, as its heavily vibe coded. Required Qualifications Convex Expert: You must have deep experience with Convex schema design, internal vs public functions, and realtime subscriptions. You know how to replace useEffect polling with reactive queries. We need the app deployed on domain fixa.dev for full payment to be released. You can use Vercel or Blaxel or Google Cloud - we do not want to pay the Vercel Pro! Next.js 15 & React 19: You are comfortable with Server Actions, RSCs, and the latest React hooks (use, useActionState). AI/LLM Experience: You understand the Vercel AI SDK, how tool-calling works, and how to manage context windows. The agent should always be loaded with a file tree, and any relevant info, and if it wants to add context, it can use tools - like read-file. We need the Agent on par with OpenCode (open source) and Claude Code. Infrastructure Aware: You understand concepts like persistent volumes, container lifecycles, and remote command execution. Sandboxes must have persistence. And they must boot to the exact same state within 5 seconds, no matter what. Screening Questions Please answer these 3 questions in your proposal: Looking at our dual-database situation (Prisma & Convex), what is your strategy for migrating the Stripe webhook handler (src/app/api/webhooks/stripe/route.ts) to use Convex mutations instead of Prisma, ensuring idempotency? In src/lib/blaxel/sandbox-service.ts, we sync files from the Sandbox back to Convex. How would you handle a race condition where the AI writes a file, but the user edits it simultaneously in the UI? We are using Tailwind v4 with @theme blocks in globals.css. Have you worked with v4 yet, and are you comfortable debugging style issues without a tailwind.config.js? We use coss ui - which is beautiful and opensource: coss.com/ui To Apply: Start your proposal with the word “BLAXEL” so I know you read the full listing. We are looking for someone who can start immediately and ship production-ready code. GitHub: https://github.com/DevEtaiGabbai/vibe/tree/coss-update-v2-fixa - NDA - No sharing or reproducing.