Senior Full Stack TypeScript Developer

Reports to: VP of Engineering

Extendly builds mission-critical tools that power thousands of marketing agencies and support hundreds of thousands of end users. Today, we are the backbone of customer experience across the GoHighLevel ecosystem. Tomorrow, we aim to become the core infrastructure through which SaaS companies and modern SMBs manage their data, relationships, and insights—with the help of AI.

We're solving some of the hardest problems in multi-tenant systems, content inheritance, and support-at-scale — all while pushing the limits of what's possible with generative AI. If you want to work at the edge of AI agents, multi-model orchestration, and deep product extensibility, this is your moment.

• Lead the design, implementation, and operation of full-stack product features across our platform using TypeScript, NestJS, React Router, Postgres, and MongoDB.
• Navigate and evolve our complex multi-tenancy inheritance model, ensuring clean boundaries and scalable, permissioned experiences for every customer type.
• Architect systems that work at scale — for hundreds of thousands to millions of end users, with high performance, high availability, and clear observability.
• Collaborate with Product, Support, and Leadership to ship outcomes, not just features.
• Build and maintain tools, services, and workflows that enhance internal velocity and enable AI-driven support experiences.
• Participate in (and often lead) design reviews, architecture discussions, and code audits with an emphasis on Extendly's high standards.
• Use AI as part of your daily toolkit, and help shape how it's used inside the product itself — from prompt chaining to autonomous agents to multi-context processors and LLM-driven Rapid Application Development.
• Mentor engineers and elevate the technical culture through documentation, demos, and hands-on pairing.
• Have 5+ years of experience building and scaling production-grade full-stack applications.
• Are fluent in TypeScript, with mastery over modern patterns in React, NestJS, and MongoDB.
• Can architect large systems with modularity, separation of concerns, and tenancy-aware logic.
• Are deeply familiar with REST APIs, GrraphQL, performance optimization, observability, and CI/CD pipelines.
• Have real-world experience with AI tooling — whether it's prompt design, using OpenAI APIs, building with LangChain/LlamaIndex, or orchestrating agents with multiple memory stores.
• Understand that AI isn't magic — and can clearly explain why it can't (yet) replace what you do, even as you use it to go faster and build smarter.
• Thrive in high-ownership, low-ego environments where speed and precision coexist.
• Believe in clean code, customer obsession, and the power of relentless iteration.

• Have experience working with multi-tenancy, inheritance trees, and permissioned content propagation. Think Git-like distributed versioning for user content
• Have built AI agents or agent frameworks, ideally using tools like OpenAI functions, LangGraph, Model Context Protocol, or memory-augmented chaining.
• Understand or have worked with multi-modal LLMs, custom embeddings, and hybrid chunking strategies.
• Have scaled features that touch hundreds of thousands of users — or systems that process millions of data points. Are capable of technical storytelling — aligning engineering complexity to business outcomes.
• Infra: Docker, Docker Swarm, GitHub Actions, AWS
• Data & Observability: Mongo Aggregations, ClickHouse, Custom Analytics, OpenTelemetry, Grafana LGTM Stack

• Reliability: We say what we'll do, and do what we say — with stable, scalable systems to match.
• Supportiveness: We unblock each other, elevate the team, and listen before we speak.
• Efficiency: We move fast — but we move with purpose and without waste.
• Work Ethic: We hustle with clarity, because execution is everything.
• Results Matter: Shipped > planned. Measured > assumed. Outcomes > output.
• Customer Obsession: We know our support is often our customers' lifeline — we act accordingly.
• Extreme Ownership: If something breaks, we fix it — even if we didn't build it.
• High Standards: We continuously raise the bar, and help others do the same.
• Humility & Kindness: No egos. Just people solving hard problems together.
• Persistence: Roadblocks don't slow us — they sharpen us.
• Client Empowerment: Everything we build makes our clients smarter, stronger, faster.
• Innovation: We invent at the edge — in AI, architecture, and automation.

This is a high-leverage role. You'll help shape the foundation of a platform that will empower not just SaaS platforms, but also the millions of small businesses that need to operate like tech companies — but don't have the in-house resources to do so.

You're not just building features. You're building the infrastructure that helps businesses of all kinds scale.

Job Type Full-Time (Remote) Location Lahore, Pakistan Application period 2025-07-04 - 2025-07-18 Salary and compensation $4000 - $5000 USD per month exclusive of taxes Have any question? drop us a line hello@solaceltd.io