SaaS Product & Scheduling Engine • 2026
otoodo
Our own SaaS product: a to-do app that does the arithmetic, working out what today has to contain for every deadline to land — and saying plainly, in hours, when one cannot.
Client
Oasis Digital
Industry
SaaS / Productivity Software
Year
2026
Platform
Next.js, Supabase and Stripe
Visual showcase
A closer look at the design, structure and digital experience.
Project overview
From business need to digital system.
otoodo is not client work. It is a product Oasis Digital designed, built, shipped and now sells, which makes it the most direct evidence of what the engineering side of the studio can do without a brief to work from. The premise is narrow and genuinely hard: every other to-do app takes your work and hands it straight back in order, but sorting is not planning. A list sorted by due date still does not know that the four things due Friday need eleven hours and you only have six. otoodo does that arithmetic — and when a deadline is already impossible, it says so, in hours, before the week starts rather than after it ends.
You can explore the live product at Oasis Digital.
Challenge
The hard part was never the interface. A naive planner that greedily fills every day to the brim puts work due in three months on today's list, and a list you cannot finish is one you stop believing. The genuinely difficult question is much narrower: what do I need to touch today so that everything still lands on time? Answering it means modelling real working hours, subtracting fixed commitments, spreading deadline work sensibly, and deciding feasibility exactly rather than guessing — then wrapping all of it in a product with authentication, subscriptions and a marketing site that can actually sell it.
Solution
We built the planner as a set of pure functions with no database and no React anywhere near them, so the scheduling logic could be tested properly rather than trusted. Recurring commitments come off the top of each day. Deadline work is then spread rather than crammed — a ten-hour task with ten working days left asks for an hour a day — served earliest-deadline-first, never in slices under thirty minutes, and aiming to finish slightly early so one bad day does not become a missed date. A separate backward pass finds every task's latest responsible start, which is where the slack figures come from. Feasibility is computed exactly, so an at-risk warning is always a real capacity problem with a real number attached, never an artefact of how the plan happened to be laid out.
What we delivered
The key systems, assets and improvements created for the project.
Deadline-Aware Scheduling Engine
The core of the product: pure, dependency-free functions that model working hours, subtract fixed commitments, spread deadline work earliest-deadline-first and never schedule a slice under thirty minutes. Covered by tests rather than by hope.
Exact Feasibility Warnings
A separate calculation that decides, for every deadline, whether the work due by then fits in the hours available by then — so a warning reads "you are 8 hours short" rather than a vague amber flag.
Backward Pass & Slack
A mirror-image pass running latest-deadline-first to find each task's latest responsible start, which is what lets the app show when something can no longer safely be put off.
Today & Calendar Views
A Today view showing fixed commitments and the day's share of project work against a capacity bar, and a month calendar that reads as a load map so an overloaded week is visible before you walk into it.
Working Hours & Overrides
Per-weekday focused hours with one-off overrides for holidays, half days or a Saturday you are working — because a planner built on assumed hours produces plans nobody keeps.
Recurring Commitments
Tasks repeating daily, every N days or on chosen weekdays, each occurrence completed or skipped on its own day, so a habit is never marked done forever.
Subscription Billing
Stripe checkout and webhooks with a free tier, a Pro plan and a fortnight of Pro on signup with no card. Entitlements are derived from what Stripe last said rather than stored, so access corrects itself when a payment fails or a refund is issued.
Voice & API Access
An HTTP endpoint a ChatGPT Custom GPT can call, so a task can be added by speaking to a phone. Tokens are Pro-gated, checked on every request and stored only as a hash.
Marketing Site & Content
A marketing site, pricing page and MDX writing section, plus comparison pages against Todoist, Motion and Notion that open by naming who the competitor suits better.
Project impact
Designed to create long-term business value.
A shipped, monetised SaaS product rather than a prototype — signup, billing, subscriptions and support all live.
A scheduling engine written as pure, tested functions, so the planning logic is verifiable rather than assumed.
Exact feasibility maths: warnings quote the precise shortfall in hours, so they can be acted on.
Stripe subscriptions where entitlements are derived from Stripe's own record, never stored as a flag that can go stale.
A voice route — tasks added by speaking to a ChatGPT Custom GPT, with natural-language dates and sensible defaults.
A marketing site with honest competitor comparisons that lead with what the alternatives do better.
Proof that the studio can take a product from an idea to a paying customer without a client brief.
Design details
Interface, brand and content details from the final delivery.
Our process
A clear process from first idea to final launch.
01
Discovery
We review the business, audience, goals, existing digital presence and project requirements.
02
Strategy
We define the structure, UX direction, content approach and technical requirements before design begins.
03
Design & build
We create the visual system, develop the platform and connect the core functionality required for launch.
04
Launch & optimise
We test, deploy, optimise performance and support improvements after the project goes live.
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