iOS Engineer

About the Role

FluxInk is bringing our next‑generation AI-powered productivity and inking experience from Windows to iOS. We are looking for a iOS engineer who is passionate about
handwriting, creativity tools, AI-assisted workflows, and high‑performance on‑device machine learning
.

You will be responsible for rebuilding the FluxInk Windows experience on top of native Apple technologies—including
SwiftUI, Metal, PencilKit, CoreML, and iOS sandboxed file architecture
. This is a highly technical role involving graphics, real-time rendering, on-device AI, and advanced editor design.

Key Responsibilities

1. Application Development & Architecture

- End-to-End Build:
Develop the FluxInk iOS app using Swift and SwiftUI.
- Performance Optimization:
Engineer a modular, fast-loading application specifically tuned for the unified memory of modern iPad and iPhone hardware.
- Feature Parity:
Ensure the iOS app maintains the same core capabilities as our Windows app while delivering a "native-first" mobile user experience.

2. Custom Inking Engine Implementation

- GPU Rendering:
Implement and refine our custom GPU-accelerated rendering engine using
WebGPU (or Metal)
.
- Input Precision:
Deeply integrate
PencilKit
while developing custom stroke smoothing, velocity filtering, and vector path modeling.
- Zero-Lag Goal:
Achieve industry-leading precision and sub-millisecond perceived latency for a true "pen-to-paper" feel.

3. Advanced Editor & Data Systems

- Markdown Native:
Build or integrate a native Markdown editor with support for frontmatter, syntax highlighting, and real-time AI assistance.
- Reliable Data Sync:
Design robust local sandboxed storage and iCloud Drive integration using
SQLite or CoreData
.
- Security:
Manage secure credential storage via the iOS Keychain.

4. Collaboration & Quality

- Team Synergy:
Work closely with Windows, backend, and AI teams to ensure seamless cross-platform document pipelines.
- Debug Tooling:
Develop internal tools for profiling render loops, ink pipelines, and AI behavior.

Required Qualifications

- Experience:
4+ years of professional experience with Swift and SwiftUI, with a portfolio of complex, high-performance apps.
- Graphics Expertise:
Proven experience with custom drawing engines, vector graphics, or GPU-accelerated rendering.
- Technical Mastery:
\* Proficiency with
WebGPU
or
Metal Performance Shaders (MPS)
.
- Solid understanding of the iOS file system, sandboxing, and background task management.
- Hands-on experience with
SQLite
,
CoreData
, and
WKWebView
.
- Execution:
Able to work autonomously, take ownership of technical challenges, and communicate effectively with cross-functional teams.

Nice to have skills:

- AI & Machine Learning:
Experience with
CoreML
and converting
ONNX/PyTorch
models for the Apple Neural Engine (ANE).
- AI Features:
Familiarity with handwriting recognition, OCR, or RAG integration.
- Hardware Integration:
Experience with Apple Pencil
Hover
and
Scribble
APIs.
- Domain Knowledge:
Previous experience shipping a major stylus, note-taking, or digital art application.

What We Offer

- Opportunity to build the
next-generation AI inking experience
on Apple platforms
- Influence over core architecture and technical direction
- Work with a world-class AI, product, and design team
- Chance to define the future of cross‑platform AI notetaking