Growth Engineer (Full-Stack)

About the role

We're starting a new growth squad at Zaapi, and you'll be its first engineer. The squad's job is to grow revenue through the product itself. That means turning new sign-ups into active merchants, getting existing customers to adopt our AI Agent, and helping them upgrade as their business grows.

You'll work day to day with our Head of Growth, who acts as the squad's product manager, and with our product designer. You'll report to our Head of Engineering, who supports your technical growth and holds your code to the same standard as the rest of the engineering team.

Our product has two halves that need to work as one. The Helpdesk is where merchants run their day-to-day customer conversations across every channel their buyers use: WhatsApp, LINE, Facebook, Instagram, Shopee, Lazada, TikTok Shop and Shopify. The AI Agent resolves those conversations automatically. It retrieves the right knowledge, follows the merchant's own procedures, and takes real actions inside marketplaces and storefronts on the merchant's behalf. Every merchant's journey through the product is an opportunity to grow: connecting a first channel, trying the AI Agent for the first time, and reaching the point where a bigger plan or more AI capacity makes sense.

One week you might be rebuilding the first-login experience so new merchants connect a channel in minutes. The next, you might be building an in-product prompt that shows a merchant how much time the AI Agent would save them, or an upgrade flow that appears exactly when they hit their plan's limits. You'll ship quickly, measure whether it worked, and iterate. You'll see your impact in revenue every week, whether from new subscribers or from existing customers growing with us.

What you'll do

• Activation, adoption and expansion (40%). Build and improve the journey from sign-up to first integration: social sign-in (Google, Outlook), the sign-up and verification flow, first-login channel setup, in-product prompts and guidance, and a smooth handoff between mobile and desktop. Build the in-product flows that drive AI Agent adoption and upgrades, such as usage prompts, upgrade paths and AI credit top-ups.
• Lifecycle messaging (30%). Build the triggers, logic and integrations behind emails and in-product nudges that bring merchants back at the right moment: to finish setting up, try the AI Agent, or upgrade when they're ready.
• Funnel instrumentation and data (20%). Own the tracking that tells us what works: event instrumentation from landing page to first integration and beyond, analytics setup (GA4, Amplitude), ad platform conversion tracking (Meta CAPI, Google Ads), and the dashboards the growth team uses every week.
• Experiments and engineering quality (10%). Design, build and measure experiments with the Head of Growth. Choose measurement approaches that give real answers at a scaling B2B startup's volumes. Ship production code that meets our engineering standards, goes through code review, and is maintainable by the wider team.

What success looks like

• In your first month, the full funnel from sign-up to first integration is properly instrumented, and we trust the numbers.
• From there, you ship a steady cadence of activation, adoption and upgrade improvements and experiments.
• You're measured on the conversions the squad owns: sign-up to first integration, AI adoption among existing customers, and upgrades.

Location

• Bangkok, hybrid: in the office 3 days a week, near Thonglor BTS station.
• We're looking for candidates based in Bangkok. Visa sponsorship is available for exceptional candidates willing to relocate.

Minimum qualifications

• 3–5 years' experience as a full-stack software engineer, shipping production code across frontend and backend.
• Strong with TypeScript, React, Node.js / NestJS and MongoDB, including authentication, event triggers and third-party APIs.
• Experience with product analytics and event instrumentation.
• Experience running experiments and A/B tests.
• A strong bias for shipping: you build quickly, measure results and iterate.
• Excellent written and verbal communication skills in English.

Preferred qualifications

• Thai language skills.
• Experience building onboarding, activation, upgrade or trial-to-paid flows at a self-serve or product-led SaaS company.
• Familiarity with Southeast Asian e-commerce and messaging platforms (LINE, Shopee, Lazada, WhatsApp).
• Experience with lifecycle email tooling, Meta CAPI or Google Ads conversion tracking.
• Experience building LLM-powered features.
• Previous experience in a growth team, or at an early-stage or fast-scaling B2B SaaS startup.

Our hiring process

1. Intro call (10 mins)
2. Technical interview (60 mins)
3. Conversation with our Head of Engineering (45 mins)
4. Conversation with our Head of Growth (30 mins)
5. Final conversation with our leadership team (15 mins)