Mobile &
Fullstack
Engineer

OVERVIEW

Timefio is my own product — designed, built, monetized, and operated solo. It helps users organize schedules, build recurring routines, and understand daily productivity through reminders, full-screen alarm flows, and recap insights with scoring and streaks. The full product surface is mine: authentication, cloud synchronization, localization (ID/EN), in-app purchases, privacy, and Play Store distribution.

OUTCOME

A complete production mobile product — scheduling workflows, reminder reliability, recap analytics, monetization, and multilingual UX — shipped and operated as a solo founder.

CONTRIBUTIONS

• End-to-end design and development in Flutter — every screen, every state
• Flexible scheduling engine with configurable recurrence and full-screen alarm flows
• Productivity recap: scoring, streaks, and period insights that turn activity into visible progress
• Full product surface: auth, cloud sync, localization (ID/EN), IAP, and Play Store distribution

CHALLENGES → SOLUTIONS

• Reliable alarm & notification delivery

  Full-screen alarm interactions with snooze/completion handling and follow-up notifications to reduce missed tasks while respecting user preferences.

• Turning activity into useful feedback

  Recap and productivity scoring based on completion, consistency, streaks, and time patterns.

OVERVIEW

An enterprise HRIS serving real daily employee operations. I worked on the v3 evolution of a live product: refactoring UI across 20+ screens to design-system guidelines, strengthening interconnected HR workflows (attendance, leave, overtime, appraisal, business trips), push-notification handling, and the OTA release lifecycle — all without disrupting active users.

OUTCOME

Sharpened a live enterprise HR product through its v3 cycle — more consistent UX, sturdier workflows, and a faster, lower-risk release loop.

CONTRIBUTIONS

• UI refactor across 20+ screens — attendance, leave, and overtime modules aligned to design-system guidelines
• Interconnected HR workflows spanning attendance, leave, overtime, appraisal, and business trips
• Push-notification handling for real-time HR workflow updates
• Shorebird OTA release lifecycle — faster iterations without disrupting active users

CHALLENGES → SOLUTIONS

• Evolving a live production app to v3

  Refactored UI and flows alongside analysts and backend engineers while preserving functionality for existing users.

• Scalability in a growing codebase

  BLoC state management and dependency injection for clarity, predictability, and long-term maintainability.

OVERVIEW

A production CRM application I helped build from scratch to support sales teams managing leads, tracking customer interactions, and monitoring performance on the go. I worked closely with business analysts and backend engineers to translate sales requirements into a structured mobile workflow — applying Clean Architecture and BLoC for predictable state management, and managing the Shorebird OTA release pipeline for ongoing production updates.

OUTCOME

Delivered a structured, efficient sales workflow — customer relationships, activities, and performance insights accessible directly from the field.

CONTRIBUTIONS

• Lead management module — data model, workflow, and UI for field sales teams
• Sales activity tracking and customer interaction logging
• Real-time reporting dashboards consumed by field teams
• Clean Architecture + BLoC across the full feature set for predictable state management

CHALLENGES → SOLUTIONS

• Translating sales requirements into a structured mobile workflow

  Collaborated closely with business analysts to model lead management, activity tracking, and reporting around how field teams actually work day to day.

• Consistent state management across a growing feature set

  Applied BLoC with clean architectural boundaries to keep behaviour predictable and the codebase maintainable as features expanded.

• Reliable deployment and update strategy

  Managed application builds, deployment pipelines, and Shorebird OTA updates, enabling faster iteration and smoother production releases.

OVERVIEW

Porto Portal is a centralized mobile gateway built to unify access to internal enterprise systems, simplifying navigation and reducing the need for multiple logins across different tools. I contributed to developing the app from scratch as part of a cross-functional team, working closely with backend engineers and business analysts to design and ship the platform.

OUTCOME

Unified access to several internal services behind a single mobile gateway, simplifying workflow navigation for employees and strengthening consistency across the enterprise mobile ecosystem.

CONTRIBUTIONS

• Core navigation and access control architecture for the unified gateway
• Flexible service-integration layer connecting to multiple enterprise back-ends
• Reusable UI component library and design tokens for cross-module consistency
• Clean Architecture patterns keeping feature modules isolated and testable
• Shorebird OTA pipeline — deployment, distribution, and iterative updates across Android and iOS

CHALLENGES → SOLUTIONS

• Unifying access across multiple internal services

  Designed a flexible navigation and access model that consolidates links to various enterprise back-end services into a single, coherent mobile interface.

• Maintaining UI consistency across a growing module surface

  Collaborated with UX designers and backend engineers to define reusable components and design tokens, ensuring visual and interaction consistency as modules expanded.

• Keeping the architecture scalable as integrations multiplied

  Adopted Clean Architecture and BLoC state management to modularize feature sets, making the portal maintainable as new internal services were onboarded.

• Smooth production rollouts across platforms

  Managed application builds, deployment pipelines, and Shorebird OTA updates, enabling efficient distribution and iterative improvements across Android and iOS.

OVERVIEW

An academic information system where I designed and implemented the digital-signature capability end to end: multi-step document approval, RSA-based cryptographic signing with SHA-256 hashing and encrypted private-key storage, PDF embedding via TCPDF/FPDI, and a public QR verification endpoint that validates authenticity without authentication barriers.

OUTCOME

Replaced manual wet-signature processes for academic documents, cut administrative overhead, and made verifiable digital approval part of daily academic operations.

CONTRIBUTIONS

• RSA-based digital-signature system — key generation, SHA-256 hashing, and encrypted private-key storage
• Multi-step document approval workflow with configurable validation rules
• PDF signing pipeline: signature embedding, QR verification, and tamper detection via TCPDF/FPDI
• Public verification endpoint — QR-based, no authentication required

CHALLENGES → SOLUTIONS

• Secure, verifiable signatures

  RSA + SHA-256 with controlled key management and identity validation for authenticity and non-repudiation.

• PDF integrity after signing

  Processing pipeline embedding signatures and QR codes directly into documents, enabling tamper detection and long-term verification.

• Public verification without login

  QR-based public endpoint validating authenticity while keeping the system itself secured.

OVERVIEW

The official app for the Informatics student association at UMT, centralizing event information, member engagement, and attendance in one platform. Built from scratch solo: modular architecture, member-only authenticated check-ins, environment-based dev/prod configuration, and Shorebird OTA updates to cut release friction.

OUTCOME

Became the association's primary digital platform for communication and event attendance — improving participation tracking and information distribution on a maintainable foundation.

CONTRIBUTIONS

• Architected and developed the entire app from scratch in Flutter
• Implemented event management with real-time updates
• Built member-only attendance with secure authentication
• Integrated Shorebird OTA updates and environment-based config

CHALLENGES → SOLUTIONS

• Maintainable architecture as a solo developer

  Clean, modular patterns keeping the codebase scalable as features grew.

• Frequent updates without user disruption

  Shorebird over-the-air updates, reducing dependency on full Play Store releases.