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01 — OVERVIEW

Lumi

Personal money. Business planning. A clearer picture.

Lumi is a financial awareness and planning product that brings personal finances and business planning into separate workspaces. It connects income, recurring costs, spending, future commitments, and interactive calculations to help people understand their current position and explore possible next steps.

Role

UI/UX & Product Designer

Responsibilities

UI Design · UX Design · Interface Design · Interaction Design

Project context

Independent · Solo

Platform

Web application

Scope

Personal finances and business scenarios

Status

Working product with features in development

The workspace overview provides separate entry points for personal finances and business planning.
02 — THE CHALLENGE

Understanding the money behind the numbers

A balance shows an amount. Planning requires understanding what affects it: recurring obligations, everyday spending, future commitments, and the costs behind an income target. Lumi brings these relationships into view through records, comparisons, and scenarios.

Central design question

How can people understand what is available and explore future scenarios while keeping recorded money distinct from planning assumptions?

01

Overview and detail

A summary needs to be easy to scan, but the records and assumptions behind it must remain accessible.

02

Shared access & separate contexts

Personal finances and business planning belong in one tool, but involve different records and terminology.

03

Useful estimates & limits

A calculation can support planning only when people can inspect its inputs, assumptions, and relationships.

03 — FINANCIAL SITUATIONS

Different questions need different views

Lumi’s structure supports three practical situations: planning between paydays, exploring future commitments, and evaluating business income against costs.

01 / Payday Planning

“What needs to be covered before my next payment, and how does actual spending compare with my plan?”

Difficulty

Income schedules and bills do not always align neatly with calendar months.

Design response

Payment-cycle workspace combining planning period, obligations, and expenses.

02 / Future Commitments

“How would a different repayment horizon change the monthly amount required?”

Difficulty

A debt total alone does not explain the relationship between time and monthly commitment.

Design response

Simulator updates required payment for a selected horizon without changing saved records.

03 / Business Scenarios

“What remains from revenue after operating costs and selected reserves?”

Difficulty

Revenue, costs, and take-home estimates answer different questions.

Design response

Project-based records and calculation breakdowns expose the inputs behind each scenario.

Note: These situations are design assumptions used to explain the experience. They have not been validated through formal user research.

04 — ARCHITECTURE & CONNECTED SYSTEM

One product. Two financial contexts. Connected records.

Lumi separates personal finances and business planning into dedicated workspaces with shared navigation, connecting detailed inputs with summaries and scenario models.

Architecture Tree & Scope Hierarchy

Hierarchical relationship between dual workspaces and shared utility services.

Lumi Root Application

Personal Workspace

  • Spending Cycle
  • Savings Goals
  • Wishlist Queue
  • Debts & Simulator
  • Calendar Reports

Business Workspace

  • Project Switcher
  • Services & Income
  • Cash Flow & Invoices
  • What If & Pricing Tools

Shared Floating Utilities

  • Profile
  • Bank connection
  • Learning
  • Financial companion

Business groups are sections within the workspace rather than separate pages.

Personal relationships

Income & fixed billsInform the payment-cycle summary.
Budgets & categorized expensesSupport planned vs actual comparisons.
Financial recordsRoll up into calendar-month reports.

Business relationships

Active projectDetermines which records and metrics display.
Service costsProvide the baseline for pricing and viability.
Project settingsSupply reserve assumptions alongside calculations.
The shared header provides access to both financial contexts.

Connected system view

Summary cards communicate period, inputs, and meaning without ambiguity.

Project context connects operating costs with planning calculations.

Business relationships

05 — DESIGN DECISIONS

Four decisions that shape the experience

These decisions explain the rationale of the current design with alternatives and structural tradeoffs. Alternative approaches explain the current design; they are not documented historical concepts tested with users.

1

Separate financial contexts, shared access

Problem

Personal and business records involve different questions and terminology.

Alternative approach

Combined workspace places all items together, requiring repeated context selection.

Current design

Dedicated Personal and Business workspaces with a shared header switch.

Tradeoff

Switching adds a step, requiring persistent cues for active context.

2

Plan by payment cycle, review by calendar month

Problem

The period used for planning differs from the period used for monthly reporting.

Alternative approach

Using calendar months everywhere ignores non-standard pay frequencies.

Current design

Spending uses payment-cycle periods; Reports provide calendar-month summaries.

Tradeoff

Requires clear period labeling so totals are not misinterpreted.

3

Explore a scenario without changing the record

Problem

Trying a repayment horizon must not be confused with committing a repayment.

Alternative approach

Placing scenario controls inside record editing blurs saved reality with what-if ideas.

Current design

Debt simulator displays dynamic payment scenarios without updating logged balance.

Tradeoff

Must explicitly differentiate exploratory slider states from saving actions.

4

Show the assumptions behind the answer

Problem

A single output figure hides the costs and reserve assumptions that produced it.

Alternative approach

Output-only calculator is cleaner but offers less guidance for decision confidence.

Current design

Business calculators show step-by-step inputs and formulas alongside totals.

Tradeoff

Requires thoughtful progressive disclosure to prevent dense visual clutter.

06 — PERSONAL PLANNING

Record the detail. Understand the position.

Lumi brings income, fixed bills and actual spending into one payment-cycle overview, with calendar-month reports for reviewing spending over time.

Record

Income & Bills

Recurring income and fixed bills establish the starting point for the plan.

Compare

Spending & Budgets

Inline transaction entry paired with planned vs actual category bars.

Reflect

Monthly Report

Calendar-month reports bring income, bills and spending together for review.

Keep actual spending distinct

An expense can include a name, amount, optional date, and category. The entry form keeps actual spending separate from the fixed-bill list.

07 — FUTURE COMMITMENTS

See the commitment. Explore the horizon.

The Debt Tracker presents an obligation alongside its monthly payment and payoff horizon. An inline simulator allows users to model durations without changing saved entries.

The debt summary brings the current obligation and estimated payoff date together.
Changing the target duration updates the required monthly payment. This is a scenario, not a recorded repayment.

Savings Goals

Connects a future target amount with allocated savings funds.

Wishlist Queue

Item capture keeps planned purchases distinct from live spending.

08 — BUSINESS PLANNING

Connect project costs with possible outcomes

Business planning combines active project context with subscription pricing and what-if simulation models.

The project overview distinguishes raw costs from monthly equivalents.
The active project's service list contains operating expenses such as tools, hosting, and subscriptions.

Subscription Pricing Calculator

Input cost per user and target margin; inspect recommended price options and VAT deduction details.

Pricing inputs and formula explanations make the calculation visible. Any example shown is a hypothetical scenario.

What If Scenario Simulator

Adjust pricing, customer count, and variable expenses to pinpoint the estimated break-even client count.

Minimum hourly rate

Works backward from desired annual take-home and billable hours.

Runway estimator

Calculates how long a cash reserve sustains selected monthly burn rate.

Salary goal planner

Converts take-home target into gross project revenue requirements.

Planning note: Outputs are estimates based on selected inputs. Calculation consistency and tax assumptions remain part of the product’s ongoing review.

Switching projects changes the active context and all associated cost baselines.
09 — COMPONENTS & INTERACTION STATES

A consistent language for complex information

Lumi uses pale backgrounds, green emphasis panels, grouped cards, and supportive language. Large amounts establish hierarchy, while labels and breakdowns explain the figures.

Product specimens

  1. Typography in Context

    Clear hierarchy and consistent typography help users scan and manage information efficiently, even in larger lists.

  2. Colour in Context

    Pale backgrounds and green emphasis panels create a calm, approachable interface while guiding attention to key information.

  3. Controls & Components

    Consistent components, such as navigation, profile cards and activity lists, help users understand where they are and what to do next

  4. Information Labels

    Labels, tags and visual groupings make it easier to understand content at a glance and find relevant information.

Interaction examples

These examples show how the interface communicates empty, error, confirmation and over-budget states.

  1. Empty State

    Neutral guidance helps users understand what to do next without confusion.

  2. Validation Error

    Clear, field-level alerts help users quickly understand and fix mistakes.

  3. Save Confirmation

    A subtle inline message confirms actions without disrupting the user's flow.

  4. Over-Budget State

    Proportional alerts use colour and clear language to highlight important information.

10 —Visual Foundations

A clear visual system for financial information

Lumi uses pale backgrounds, green accents and grouped cards to organize financial information. Prominent amounts highlight key totals, while labels and breakdowns explain what each figure represents.

01 / Typographic Foundation

2 Typefaces
AaTypeface 01

Plus Jakarta Sans

Medium 500 · SemiBold 600 · Bold 700 · ExtraBold 800

Used for display headings and prominent financial figures. Larger sizes give key totals emphasis within the page hierarchy.

In context

Safe to spend: $11,300

09Typeface 02

Manrope

Regular 400 · SemiBold 600

Used for body text, navigation, labels, buttons, inputs and smaller headings. Size and weight distinguish supporting information from actions and section titles.

In context

RUNWAY 14.2 MONTHS

02 / Color System

1 Palette

Terra Modern Core

Pale backgrounds separate the page from its cards and inputs. Green accents highlight key information and primary actions. Supporting text and borders provide quieter structure, while feedback colours identify states that need attention.

5 colors
Soft Mint White
#edf4edPage background
Muted Sage Green
#688863Cards & panels
Powder Sage
#bfd4c2Primary actions & labels
Deep Forest Green
#1f2a24Panels & text
Pure White
#ffffffCards & Inputs

03 / Iconographic Vocabulary

1.5px Line Stroke
Liquidity
Cycle
Escrow
Payoff
Business
Simulate

Simple line icons with a consistent stroke weight label the core financial concepts, so each one stays recognisable across the Personal and Business workspaces.

04 / Component Anatomy & Archetypes

Interactive Primitives

Component examples showing button states, inputs and content cards. Sample figures and entries are illustrative.

LifestyleCancel
How much do you want it?
Open link
Oct 1 - Nov 1, 2026

Payment day for this month: 1

Click to set a custom date for this month

Financial PeaceOn track
Money left€1,396.18

Your monthly plan is holding steady.

You're in a good position after bills and spending.

You can safely spend

€66.48 / day

Keep it up!

You're on track.

€2,834.46

Fixed Bills

€1,438.28

20 days until next payment

Budget Used

0%

Under budget €384.00

High Savings Rate

Remaining Rate

49.3%

Lumi · Visual Design SystemA visual language for calm financial decisions
11 — EVALUATION & REFINEMENT

What the product review revealed

I used an AI-assisted critique to identify potential usability issues, then reviewed the suggestions against the product and prioritised refinements.

Finding 01

Financial definitions

Observation

Payment-cycle and calendar views use different timeframes; daily allowance needs clearer documentation.

Proposed refinement

Make summary periods, cost bases, and underlying assumptions explicit across all related views.

Finding 02

Navigation and completion

Observation

Some destinations do not strictly match nav labels, and several settings interactions remain incomplete.

Proposed refinement

Align labels with destinations and visibly badge features currently in active development.

Finding 03

States and accessibility

Observation

Over-budget empty copy needs calibrated tone; form fields require persistent labels for screen readers.

Proposed refinement

Match status messages to financial reality; audit keyboard focus and mobile touch target sizes.

Accessibility note: The product review found semantic controls and visible keyboard focus in inspected states. Persistent labels, contrast, keyboard behaviour, and responsive layouts require further verification.

What remains to validate

  • Can a new user immediately identify their active payment cycle period?
  • Can they cleanly distinguish a fixed recurring bill from a discretionary expense?
  • Can they explain why a calendar-month report differs from a cycle summary?
  • Can they explore debt horizon scenarios without fearing their balance was saved?
  • Can they identify the costs and reserve assumptions behind a business calculation?
12 — FINAL EXPERIENCE & REFLECTION

Three ways to understand the money

01 / Plan my month

Payment Cycle Journey

  1. 1Review income and fixed bills
  2. 2Compare planned vs actual spending
  3. 3Record new expenses inline
  4. 4Review calendar-month report
Personal connects detailed financial records with planning and review views.
02 / Explore debt payoff

Future Commitments Journey

  1. 1Inspect total liability & interest
  2. 2Adjust target payoff duration slider
  3. 3Compare recalculated monthly cost
  4. 4Retain saved balance intact
The payoff simulator makes an alternative repayment scenario visible.
03 / Evaluate business

Business Scenario Journey

  1. 1Select client project workspace
  2. 2Inspect service baseline costs
  3. 3Input client tier & volume assumptions
  4. 4Inspect break-even take-home breakdown
Project context and calculation breakdowns support the exploration of business assumptions.

Current Delivery

A working product with separate Personal and Business workspaces, financial records, monthly reports, debt simulation, and business calculators. Some features remain in development.

Next Steps

Unify definition tooltips, complete in-progress configuration flows, and test core navigation patterns with users across desktop and mobile devices.

Reflection

Clarity in financial tools depends upon consistent labels and assumptions across views. Periods, assumptions, and terminology must align as people move between recording daily facts and exploring speculative future possibilities.