Drawing register

Proof, framed by what it demonstrates

A club platform is multi-tenant SaaS engineering. A drawing set becoming a priced bill is document intelligence. Read these for the engineering underneath rather than the industry on top, because the industry on top is the part least likely to be yours.

Five pieces of work: three live, one a prototype and one a proof of concept. Nothing here is described as more finished than it is. What each word means.

Sheet
A-01
Title
Work
Issued for
Information
Drawn by
Snilld

Adoption across a very wide user baseMembership and hospitalityLive

Multi-tenant SaaS in productionSport and recreationLive

Document and drawing intelligenceManufacturing and fit-outProof of concept

Confidential records — isolation and auditHealthcarePrototype

Offline-first multi-tenant business appSales and business developmentLive
Preview · W-016 screens
The home screen of an invented demo club: a greeting to the member, an illustration of the clubhouse and its courts, and the member’s next booking.
01 / 06The club, on a member’s phone
A booking screen listing the tennis, squash and badminton courts with what is free now, the coach for each, and games that want a player.
02 / 06Book a court
The same booking screen switched to a junior member, showing only what juniors may book and saying that adult open games are not offered.
03 / 06Booking for a child
The members’ book: an alphabetical directory of invented members with their membership type, the year they joined and their sections.
04 / 06The members’ book
The noticeboard: upcoming fixtures, and a question put to members about extending court hours, with three answers to choose from.
05 / 06Notices, and a question put to members
The booking screen in large-text mode, with bigger headings, labels and buttons.
06 / 06Large text, for older members

Demo data. Every name and number is invented.

Read sheet W-01 ↓
Preview · W-024 screens
The home page of a demo swimming club: its own badge and colours, a pool drawn at rest with the time of the next session, and buttons to join or find a program.
01 / 04A demo swimming club
The home page of a demo football club on the same platform, in its own green, with a court drawn at rest and the time of its next session.
02 / 04A demo football club, same code
The swimming club’s programs: Learn to Swim for ages six to ten, with its weekly batches, their times and how many places are left in each.
03 / 04Programs and batches, with places left
The football club’s programs on the same screen: Grassroots Football for ages six to ten, its batches and places left, in the football club’s colours.
04 / 04The same screen, another tenant

Demo data. Every name and number is invented.

Read sheet W-02 ↓
Preview · W-036 screens
Every job on an invented fit-out line: counts at the estimate, design, check and site steps, and a card for each job saying what it waits on, such as three flagged lines in a bill.
01 / 06The line, on an invented week
Three lines the reading was unsure of, each asked as a question: a logo whose size the drawing does not give, an LED strip read at 78 per cent, and a driver the drawing does not show. Each has Correct and Fix it.
02 / 06What it is unsure of, asked rather than guessed
The quote for an invented wall bay: materials, then wastage, overheads, labour and profit, and a quote total. The send button stays disabled until three more questions are answered.
03 / 06Priced, but not sent until every question is answered
A wall bay set to 1,200 mm wide, its shelves drawn sagging in the 3D view, and a red note that the shelf span breaks the maximum unsupported span for the board and needs a mid-span support.
04 / 06A size that breaks a structural rule is blocked
A generated elevation sheet for an invented wall bay: front and side elevations dimensioned in millimetres, and a title block marked for approval.
05 / 06The drawing set, generated
The finish check for a built unit: points such as measured sizes against the drawing, handles level and shelves straight, each with OK or Problem, and a count of points checked.
06 / 06Finish QC, point by point

Demo data. Every name and number is invented.

Read sheet W-03 ↓
Preview · W-045 screens
A tenant isolation panel for an invented polyclinic: the session is marked isolated, with its workspace, tenant key and host, and no other workspace loaded.
01 / 05One session, one workspace
A read from another clinic’s workspace shown as SQL, returning zero rows, with a note on why the answer is zero rows rather than permission denied.
02 / 05Another clinic’s records: zero rows
Sealed session notes behind a PIN, with the ciphertext the database actually stores and a note on how production would harden the key.
03 / 05Sealed; the database holds only ciphertext
An unsealed session note for an invented client, with a symptom trajectory chart and a working formulation, visible only to the clinician.
04 / 05Unsealed for the clinician alone
An append-only audit trail of three rows: the notes decrypted, a session note encrypted and saved, and the sign-in, each with its time, actor and workspace.
05 / 05Who saw what, and when

Demo data. Every name and number is invented.

Read sheet W-04 ↓
Preview · W-053 screens
A morning briefing: pipeline value, deals won this month, conversion rate, today’s priority deals and what is due next.
01 / 03The morning briefing
An analytics screen with a conversion funnel, a revenue heatmap, days spent in each stage and a won-to-lost ring.
02 / 03Where deals slow down
A customer page for an invented company, with lifetime revenue, order history and tabs for notes and activity.
03 / 03After the deal is won

Demo data. Every name and number is invented.

Read sheet W-05 ↓

Sheet W-01 · Adoption across a very wide user base · Membership and hospitality

Live

Our operating system for members’ clubs: court booking, dining, guests, directory and committee governance, built for a membership whose youngest user is nine and oldest is ninety.

The home screen of an invented demo club: a greeting to the member, an illustration of the clubhouse and its courts, and the member’s next booking.
01 / 06The club, on a member’s phone
A booking screen listing the tennis, squash and badminton courts with what is free now, the coach for each, and games that want a player.
02 / 06Book a court
The same booking screen switched to a junior member, showing only what juniors may book and saying that adult open games are not offered.
03 / 06Booking for a child
The members’ book: an alphabetical directory of invented members with their membership type, the year they joined and their sections.
04 / 06The members’ book
The noticeboard: upcoming fixtures, and a question put to members about extending court hours, with three answers to choose from.
05 / 06Notices, and a question put to members
The booking screen in large-text mode, with bigger headings, labels and buttons.
06 / 06Large text, for older members

Demo data. Every name and number is invented.

Goes in
A noticeboard, a phone call, and a secretary who remembers everything
What we built
Booking, announcements, an open-play partner board, a directory and guest passes
Comes out
A member does it on their own phone — in large-text mode or kids mode if they need it
The line it does not cross
Each club is isolated by Postgres row-level security, not by application code alone

Note 1 · The constraint

A heritage private members’ club in Goa with more than 2,500 members runs on a noticeboard, a phone call and a secretary who remembers everything. Existing club software is priced for the United States and assumes members who will happily learn a new app. Most of this membership will not.

Note 2 · What transfers

The discipline that decides whether a shop floor, a depot or a field team actually uses what you commissioned. Most systems in this bracket fail on adoption rather than on features.

Members at launch club
2,500+
Client
Anonymised
Isolation
Postgres row-level security
Hosting
Oracle Cloud, India region
Accessibility
WCAG 2.2 AA as the floor
Interactive demo
Public, no sign-up
The full write-up →clubs.snilld.in/demo →A platform we operate →

Sheet W-02 · Multi-tenant SaaS in production · Sport and recreation

Live

Our operating system for sports academies and activity clubs: one codebase serving several fully branded tenants with isolated data and role-based access, running in production.

The home page of a demo swimming club: its own badge and colours, a pool drawn at rest with the time of the next session, and buttons to join or find a program.
01 / 04A demo swimming club
The home page of a demo football club on the same platform, in its own green, with a court drawn at rest and the time of its next session.
02 / 04A demo football club, same code
The swimming club’s programs: Learn to Swim for ages six to ten, with its weekly batches, their times and how many places are left in each.
03 / 04Programs and batches, with places left
The football club’s programs on the same screen: Grassroots Football for ages six to ten, its batches and places left, in the football club’s colours.
04 / 04The same screen, another tenant

Demo data. Every name and number is invented.

Goes in
One codebase, one deployment, one owner console
What we built
The host decides which tenant you are, and every query is scoped to it
Comes out
Four branded sites, each with its own content, roles and members
The line it does not cross
No tenant can read another tenant’s data

Note 1 · The constraint

An operator running more than one site, brand or franchise usually ends up with a separate installation per customer. Every change then has to be made several times, and the copies drift apart within a year.

Note 2 · What transfers

This is the engineering that lets one system serve many customers, branches or franchisees without forking it per customer. A vendor portal, a dealer network or a multi-site operations tool is the same problem wearing different clothes.

Tenants live
Four
Public club sites
Two, each on its own domain
Automated tests
~1,290
Hosting
Oracle Cloud, Hyderabad
Tenant isolation
Per-tenant data scoping
Clients
Anonymised
The full write-up →A platform we operate →

Sheet W-03 · Document and drawing intelligence · Manufacturing and fit-out

Proof of concept

Drawing sets become priced bills of quantities, recurring fixtures are redrawn to a new site’s dimensions, and finish checks run from a phone, with anything uncertain flagged rather than guessed.

Every job on an invented fit-out line: counts at the estimate, design, check and site steps, and a card for each job saying what it waits on, such as three flagged lines in a bill.
01 / 06The line, on an invented week
Three lines the reading was unsure of, each asked as a question: a logo whose size the drawing does not give, an LED strip read at 78 per cent, and a driver the drawing does not show. Each has Correct and Fix it.
02 / 06What it is unsure of, asked rather than guessed
The quote for an invented wall bay: materials, then wastage, overheads, labour and profit, and a quote total. The send button stays disabled until three more questions are answered.
03 / 06Priced, but not sent until every question is answered
A wall bay set to 1,200 mm wide, its shelves drawn sagging in the 3D view, and a red note that the shelf span breaks the maximum unsupported span for the board and needs a mid-span support.
04 / 06A size that breaks a structural rule is blocked
A generated elevation sheet for an invented wall bay: front and side elevations dimensioned in millimetres, and a title block marked for approval.
05 / 06The drawing set, generated
The finish check for a built unit: points such as measured sizes against the drawing, handles level and shelves straight, each with OK or Problem, and a count of points checked.
06 / 06Finish QC, point by point

Demo data. Every name and number is invented.

Goes in
A multi-sheet drawing set or a fixture to adapt, exactly as the client sent it
What we built
Layout-aware extraction and vision for reading, rule-checked parametric redesign for drawing
Comes out
A bill of quantities in the manufacturer’s own tender spreadsheet, or a fabrication-ready drawing set
The line it does not cross
A line it cannot read is left blank, and a design that breaks a structural rule is blocked rather than drawn

Note 1 · The constraint

A luxury interior fit-out manufacturer working across two hubs spends days reading client drawings before pricing can begin, redraws the same fixtures by hand for every new store, and checks finishes by eye on the factory floor. Rushed bids lose margin. Slow bids lose the job. The company cannot install new hardware in the factory and cannot expose its ERP, so anything we build has to work from the files and the phones already there.

Note 2 · What transfers

Any business that quotes from documents it did not author has this problem — tenders, specifications, schedules of work, supplier price lists. The reading is the bottleneck, not the arithmetic, and the same design carries to any repeat engineering work that is redrawn by hand.

Stage
Proof of concept, next steps in progress
Client
Anonymised
Modules
Estimating, CAD redesign, finish QC, field
Validated against
Six real past projects
Automated tests
981 backend, 34 accuracy harness
Inputs
PDF, DWG, DXF, XLSX, phone camera
Integration
File in, file out. No ERP coupling.
The full write-up →

Sheet W-04 · Confidential records — isolation and audit · Healthcare

Prototype

A working prototype of the isolation and audit design needed where confidentiality is contractual rather than optional.

A tenant isolation panel for an invented polyclinic: the session is marked isolated, with its workspace, tenant key and host, and no other workspace loaded.
01 / 05One session, one workspace
A read from another clinic’s workspace shown as SQL, returning zero rows, with a note on why the answer is zero rows rather than permission denied.
02 / 05Another clinic’s records: zero rows
Sealed session notes behind a PIN, with the ciphertext the database actually stores and a note on how production would harden the key.
03 / 05Sealed; the database holds only ciphertext
An unsealed session note for an invented client, with a symptom trajectory chart and a working formulation, visible only to the clinician.
04 / 05Unsealed for the clinician alone
An append-only audit trail of three rows: the notes decrypted, a session note encrypted and saved, and the sign-in, each with its time, actor and workspace.
05 / 05Who saw what, and when

Demo data. Every name and number is invented.

Goes in
A session note, in a practice that cannot treat records casually
What we built
Per-tenant scoping, encrypted notes, and an append-only audit trail
Comes out
A record whose history can be shown rather than asserted
The line it does not cross
A correction is a new entry. Nothing is overwritten.

Note 1 · The constraint

An independent practice carries a documentation burden but cannot accept a tool that treats patient records casually. The interesting question is not whether a model can draft a note. It is whether the surrounding system can prove who saw what, and when.

Note 2 · What transfers

The same design applies wherever confidentiality is a contractual obligation — legal files, HR records, financial casework, anything covered by a data processing agreement.

Stage
Prototype. Storage simulated.
Audit model
Append-only
Isolation
Per-tenant scoping
Not claimed
Production security
The full write-up →

Sheet W-05 · Offline-first multi-tenant business app · Sales and business development

Live

Our sales cockpit: a morning briefing, the pipeline as a board, contacts and companies, a timeline of every call and message, and a page per customer once the deal is won. Multi-tenant, invite-only, and usable without a signal.

A morning briefing: pipeline value, deals won this month, conversion rate, today’s priority deals and what is due next.
01 / 03The morning briefing
An analytics screen with a conversion funnel, a revenue heatmap, days spent in each stage and a won-to-lost ring.
02 / 03Where deals slow down
A customer page for an invented company, with lifetime revenue, order history and tabs for notes and activity.
03 / 03After the deal is won

Demo data. Every name and number is invented.

Goes in
Deals in a spreadsheet, notes in WhatsApp, follow-ups in someone’s head
What we built
A local-first app that reads from a validated copy in the browser and syncs a queue of changes
Comes out
A briefing, a pipeline and a timeline per customer, on any phone, with or without signal
The line it does not cross
The server takes the workspace from the signed-in session, never from the request, so one company cannot read another’s

Note 1 · The constraint

A small sales team works from its CRM all day, often on a phone with a weak signal. Most CRMs answer with slow page loads and a grey table per screen, so the real notes end up in WhatsApp and the CRM falls behind the truth.

Note 2 · What transfers

Any team that works from a phone away from a desk, in sales, service, collections or site visits, needs the same two things: a screen that is fast on a bad connection, and data that is never shared across customers. The same design carries to a field-service log, a dealer portal or a case tracker.

Business app
Multi-tenant, invite-only
Sign-in
Google
Automated tests
199 app, 27 API
Hosting
Cloudflare Pages and D1
Runtime dependencies
None
Public demo
Invented companies, no sign-in
The full write-up →crm.snilld.in →

Legend

How to read this register

Four status words and two rules. The words are load-bearing: each one is a claim about how finished something is, and we use them literally.

Live
Running in production and used by people who are not us. If it says live, you can look at it.
In build
Being built now, with a client, against a date. Some of what is described is working and some of it is not finished.
Prototype
Demonstrates a design rather than carrying real load. Where the stored state is simulated instead of a production database, the facts panel says so.
Proof of concept
Proves the hard part works on real inputs. It is not a product and it is not in production.
Clients
Anonymised. No client is named unless they have given written permission, so most entries describe the organisation rather than naming it. The constraint and the engineering are described exactly as they are.
Numbers
No accuracy or confidence figure appears anywhere on this page, because none has been measured under conditions we would be willing to publish.

Related drawings

Two of these are platforms we operate

Both are live and both have their own site. Sports OS has published pricing; Club OS is quoted per club while we onboard founding clubs.

Sports OS, the operating system for sports and activity clubs →Club OS, the operating system for members’ clubs →