Mid-Level Software Engineer (Full-Stack: Flutter + TypeScript + Applied AI)

Posted 6 hours ago

Worldwide

Summary

You'll be a hands-on engineer working across our whole product: the Flutter consumer app, the AI coach and publishing platform, and the Supabase backend they share. You'll own features end to end - scoping, building, testing, shipping, and monitoring them - with a high degree of autonomy and trust. We're hiring at mid level, deliberately: as the business grows, we want this person to grow into a senior technical leader on the product. You'll get increasing ownership of architecture decisions, internal tooling, and engineering practices as you demonstrate you can carry them. What you'll actually work on Consumer features in the Flutter app (iOS, Android, web): the coach chat experience, the audio player, onboarding and subscription flows. The AI lifestyle coach - our flagship AI feature, and real agentic engineering: an LLM coach with selectable personas, long-term memory (it extracts and recalls what matters to each reader across sessions), and a toolbox of actions - recommending books, pulling chapter content, saving daily intentions and takeaways, tracking goals — with safety guardrails and context management (compaction, resumable sessions) built in. The AI publishing pipeline — the machine that turns a raw book PDF into a polished, multi-language product: parsing → LLM summarization → translation → AI cover generation → ElevenLabs text-to-speech with audio stitching, orchestrated as durable, crash-safe workflows Backend work in Supabase: Postgres schema and migrations, Deno edge functions (payments webhooks, notifications, the coach backend). Internal tooling: publishing scripts, the LLM eval harness, developer-experience improvements. If a manual process annoys you, you're empowered to automate it. CI/CD: we run GitHub Actions, Codemagic mobile builds, and migration-validation pipelines — you'll help keep releases boring and frequent, and raise the bar on testing and deployment practice. AI-assisted development is how we work: we use AI coding tools (Claude Code and similar) as a core part of feature development, and we expect you to use them well — including knowing when not to trust them. What we're looking for These are our must have requirements. If you meet most of them, please apply. 4+ years of professional software engineering experience, including features you've shipped to production and supported afterwards. Strong in our two main stacks - Flutter/Dart and TypeScript/React Production experience with a relational database (we use Postgres via Supabase). Able to work independently in a remote team: you can take a loosely-defined feature, scope it, ask the right questions in writing, and drive it to done. Working proficiency in English (our working language). Degree in a STEM subject Nice to have (genuinely optional) Supabase, or Next.js App Router experience Building LLM-powered features (prompting, evals, AI SDK / LangChain-style tooling) Mobile release experience (App Store / Play Store, Codemagic or fastlane) Payments and subscriptions (Stripe, Adapty/RevenueCat)

  • More than 30 hrs/week
    Hourly
  • 6+ months
    Duration
  • Intermediate
    Experience Level
  • $15.00

    -

    $35.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

Contract-to-hire opportunity

This lets talent know that this job could become full time.
Learn more
Skills and Expertise
Mandatory skills
TypeScript
Flutter
LLM Prompt
Activity on this job
  • Proposals:50+
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Sep 1, 2025
  • NLD
    Vessem8:53 PM
  • $20K total spent
    37 hires, 24 active
  • 815 hours
  • Tech & IT
    Small company (2-9 people)

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