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Case study · Feedback tooling
QR Feedback
A feedback tool whose real product was physical: bulk-generated QR stickers a business puts on a counter, and the form behind them.
Live · Phase 3 in progress
- Engagement
- MVP design and engineering
- Platforms
- Web application and admin dashboard
- Role
- Full-stack engineering
- Market
- Germany Verify before publishing
- Industry
- Consumer feedback
- Users
- Businesses and their customers
- Output
- Printable QR stickers
- Platforms
- Web
- Role
- MVP build
- Status
- Live
01The business situation
Feedback fails at the moment of asking.
Businesses want feedback and customers are willing to give it, but only in the few seconds before they walk away. Sofa Networks GmbH of Germany set out to close that gap with something physical: a sticker on the counter that turns a scan into a form. Which meant the product was only half software: the other half was a printable sheet of QR codes that had to work when it came off a real printer.
Core challenge
Generate QR stickers in bulk that stay scannable in print, and put a feedback form behind them that a customer will actually finish.
Before
Feedback requested after the moment has passed
- Email Surveys
- Delayed Requests
- Low Response
- No Context
After
Feedback captured at the counter, in seconds
- Business
- QR Sticker
- Customer
- Response
QR Feedback Platform
02The system at a glance
One tool. Four connected parts.
- Admin Dashboard Batches, businesses and stickers
- Customer Form Scan straight into feedback
- Sticker Generation Print-ready PDFs in bulk
- Unregistered Stock Stickers claimed after purchase
Core PlatformPrint-first, phased delivery
- QR Generation
- Bulk PDF Export
- Feedback Forms
- German Localisation
- Unregistered Stickers
- Response Collection
03Workflow 01
The deliverable comes out of a printer.
An administrator generates a batch of stickers for a business as a print-ready PDF. Everything downstream depends on those codes surviving the trip to paper at the size they will actually be used.
assets/portfolio/qr-feedback/workflow-stickers.png · 16 / 11
- Bulk, not one at a timeStickers are produced in batches sized for a real business rollout.
- Print-ready outputThe output is a PDF laid out for printing rather than a screen graphic.
- Sized for the counterCodes are generated at defined physical sizes, because a sticker is a physical object.
04Workflow 02
Scan, answer, done.
The customer side is deliberately thin. A scan opens the form, the form is in the customer’s own language, and the response is recorded. Anything more would cost responses.
-
1Scan the sticker
Image placeholder A counter sticker being scanned by a phone, opening the feedback form directly. assets/portfolio/qr-feedback/step-scan.png · 1 / 2.04 -
2German-language form
Image placeholder The feedback form in German: rating, comment field and submit, kept to a single short screen. assets/portfolio/qr-feedback/step-form.png · 1 / 2.04 -
3Response recorded
Image placeholder Confirmation after submission, with the response appearing in the business’s collected feedback. assets/portfolio/qr-feedback/step-response.png · 1 / 2.04
05Workflow 03
Three phases, each shipped and learned from.
The client divided the work deliberately: generation first, the customer side second, and a third phase built entirely from what the first two revealed.
- Generation before captureThe first phase shipped only the sticker pipeline, which is what the business needed to start.
- Stickers that sell themselvesUnregistered stickers can be bought off a shelf and claimed afterwards by the business that uses them.
- A phase for the lessonsThe third phase exists specifically to absorb feedback from the first two rather than to add new scope.
assets/portfolio/qr-feedback/phase-progression.png · 16 / 10
assets/portfolio/qr-feedback/unregistered.png · 1 / 2.04
06Engineering behind the product
The system behind a scannable sticker.
A small product with one genuinely fiddly technical problem sitting right at its centre.
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QR generation at fixed sizes
Codes are produced at defined physical dimensions so they scan reliably once printed on a real sticker.
-
Pixelation control
Keeping codes crisp at the required sizes was the main technical challenge, and it governs whether the product works at all.
-
Bulk PDF composition
Batches are laid out into print-ready documents rather than exported one code at a time.
-
Unregistered sticker model
A sticker can exist before it belongs to anyone and be claimed by a business afterwards.
-
German localisation
The customer-facing product shipped in German for its first market rather than in English with a translation layer bolted on.
-
Queue-backed generation
Batch generation runs through a queue so a large export does not block the dashboard.
-
Split process deployment
Backend and frontend run as separate managed processes behind one web server.
07Technical architecture
Under the hood
A Django application with the backend and front end running as separate managed processes behind one web server.
Backend
- Django
- Django REST Framework
Frontend
- Vue.js
- Tailwind CSS
Async
- Redis
- Celery
Cloud & serving
- DigitalOcean
- Nginx
- Gunicorn
- supervisor
- pm2
Localisation
- German (first market)
Delivery tooling
- Slack
- Google Sheets
08Delivery journey
How the tool was delivered.
-
Idea stage
Scope the MVP with the client
-
Phase 1
Sticker generation and PDF export
-
Phase 2
Customer form and unregistered stock
-
Testing
Three rounds before release
-
Release
Live for the client’s customers
-
Phase 3
Iterations from earlier phases
-
Support
Maintain phases one and two
Phases one and two are live and supported; phase three is in progress. Dates and durations are withheld until confirmed. Verify before publishing
09What the system enabled
What the delivered tool enabled
- QR stickers generated in bulk as print-ready PDFs
- Codes that stay scannable at real sticker sizes
- A one-screen feedback form in the customer’s language
- Unregistered stickers sold and claimed afterwards
- Feedback collected at the point of service
- A phased release absorbing its own lessons
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