--- title: SecretoCho Design description: "I design and engineer whole products, end to end: brand, design system, web, native iOS, backend and infrastructure." url: https://secretocho.design/ type: WebPage --- # SecretoCho Design > I design and engineer whole products, end to end: brand, design system, web, native iOS, backend and infrastructure. ## I design and engineer whole products, end to end. Brand, design system, web, native iOS, backend, infrastructure. Two products live, one launching. **Abdullah Kahvecioglu** · Lead Design Engineer, DC Development · Belgrade [open to design engineer roles · cv](https://secretocho.design/cv/) - [**Novi Kvadrat** · property platform · Serbia · since Dec 2025 · novikvadrat.rs · LIVE](https://secretocho.design/work/novi-kvadrat/) - [**ProbaBaby** · twins-first baby tracker · May 2026 · v1.0.4 · LIVE](https://secretocho.design/work/probababy/) - [**Sultana Express** · B2B sourcing · Türkiye · beta · Nov 2026 · IN BUILD](https://secretocho.design/work/sultana-express/) [cd ./work](https://secretocho.design/work/) // 01 · **live** · for Novi Kvadrat Group DOO ## A five-language property platform for Serbia, built end to end. Marketplaces, business portal, admin console and in-browser floor-plan and 3D studios. Designer and developer in a core team of four since December 2025. - 277 pages - 5 languages - 390 migrations · RLS on every table *Diagram: Floor Plan Studio, step by step: a calibration line locks the scale at 6.00 metres; walls are traced with 90-degree snaps until the loop closes; four rooms flood with their areas, 58.5 square metres in all; doors and windows snap onto the walls; three photos land in their rooms and camera cones turn to their bearings; the readiness checks pass and the plan becomes a listing in five languages.* rent + sale · admin + portal · 5 languages a scanned plan goes in. **a walkable listing comes out.** [open ./novi-kvadrat](https://secretocho.design/work/novi-kvadrat/) // 02 · **live** · App Store · v1.0.4 ## A twins-first baby tracker I designed and built, shaped every day by its first real user. Pregnancy, newborn and postpartum tracking for iPhone, iPad and Apple Watch, in 32 languages. - 32 languages - 8 Live Activities · 17 widgets - offline-first sync *Diagram: One timer, two phones: phone A starts a feed and writes it locally; the server upserts it under a one-active-session lock; a trigger sends push-to-start through APNs, and phone B's Lock Screen shows a read-only mirror of the same running timer. When phone B stops it, the canonical row closes and every mirror clears.* live activities 8 · widgets 17 · sync scenarios 25 start it on one phone. **the other one already knows.** [open ./probababy](https://secretocho.design/work/probababy/) // 03 · IN BUILD · beta November 2026 ## A B2B sourcing marketplace for Turkish manufacturing, rebuilt as a platform. As CTO, I’m rebuilding it from a no-code prototype in Go, Next.js and SwiftUI. - 145-phase plan · 45 ADRs - 556 API operations - 4,430 visual baselines *Diagram: Escrow, money moves when goods do: the buyer's deposit passes an idempotency gate, where a duplicate webhook is a no-op, into an escrow vault; the double-entry, append-only ledger always sums to zero. On the buyer's QC acceptance a T plus 1 release splits the money to supplier, commission and tax, and the supplier payout waits for a KYB seal. The live-payments leg is in test mode, drawn faint.* ∑ = 0 · T+1 release · payout after KYB money moves when goods do. **not before.** [open ./sultana-express](https://secretocho.design/work/sultana-express/) // 04 · SHIPPED · Q3 2025 · for Axel Properties ## A brand system for a riverside development, from mark to signage. Logo suite, colour, type, icons and patterns, in guidelines that hold from print to signage. Design Lead, 2025. - 42 assets - 38 guideline sections - 15 colours · NCS, RAL, Pantone *Diagram: Logo construction, drawn from the brand's construction sheet. Dashed guides: horizontals at the square's top and bottom, the tops of the strokes, the step, the pillar's top and the baseline; verticals at the square's sides and the pillar's sides; diagonals that extend the strokes' edges beyond the square and cross at the apex, the top of the A. The square and its strokes fill in along those lines; the pillar is the small rectangle at the base. Clear space: 2x around the symbol, 1x between symbol and wordmark; minimum size 32 pixels.* symbol + wordmark · NCS · RAL · Pantone · 3 typefaces one mark on a grid. **every surface follows.** [open ./axel-properties](https://secretocho.design/work/axel-properties/) \[HOW\] the method, not the headline ## Products get built in a loop. Listen, decide, explore, build, prove, run, and listen again. Agents work at four of the seven stations; the call is mine at all of them. *Diagram: The method as a loop of seven stations: listen, decide, explore, build, prove, run and listen again; agents work at listen, explore, build and prove* - 14 sub-phases on one Saturday - 4 directions → 1, after 8 rounds - 57,423 tests passing [cd ./method](https://secretocho.design/method/) \[CAP\] 17, each with its proof ## What I do, and where to see it. ### design/ - [Brand and identity](https://secretocho.design/work/axel-properties/ "Axel Properties: logo suite, colour, type; ProbaBaby’s mark") - [Design systems](https://secretocho.design/work/novi-kvadrat-design-system/ "Novi Kvadrat: 187 colour roles, one system on every surface") - [Motion and diagram language](https://secretocho.design/work/sultana-express/ "Sultana’s Living Diagrams") - [Product thinking and UX research](https://secretocho.design/work/probababy/ "ProbaBaby’s data-led twins pivot") - [Enterprise product design](https://secretocho.design/archive/ "CPM Software 2020–22") - [Creative coding](https://secretocho.design/lab/ "28 public Framer components") ### engineering/ - [Frontend and web](https://secretocho.design/work/novi-kvadrat/ "Novi Kvadrat: 277 pages, Floor Plan Studio") - [Native Apple platforms](https://secretocho.design/work/probababy/ "ProbaBaby: Watch, widgets, Live Activities") - [Backend and distributed systems](https://secretocho.design/work/sultana-express/ "Sultana: Go monolith, outbox → JetStream") - [Data, maps and 3D](https://secretocho.design/work/novi-kvadrat/ "Novi Kvadrat 3D buildings, official-data pipeline") - [AI inside products](https://secretocho.design/work/novi-kvadrat/ "Novi Kvadrat: validated-filter AI search") - [Payments and money correctness](https://secretocho.design/work/sultana-express/ "Sultana’s double-entry escrow ledger") ### quality/ - [Security and data integrity](https://secretocho.design/work/novi-kvadrat/ "RLS everywhere, default-deny authorization") - [AI-orchestrated delivery](https://secretocho.design/work/novi-kvadrat/ "gated agent builds, mutation-tested SQL proofs") - [Infrastructure, CI and release](https://secretocho.design/work/sultana-express/ "sharded visual wall, release control plane") - [Localization and accessibility](https://secretocho.design/work/probababy/ "32 languages, right-to-left included") ### leadership/ - [Technical leadership](https://secretocho.design/work/sultana-express/ "145-phase plan, 45 ADRs") [cat ./about](https://secretocho.design/about/#capabilities) \[LAB\] ## Experiments and notes. [ls ./lab](https://secretocho.design/lab/) - [SC Neon Wave Shader](https://secretocho.design/lab/sc-neon-wave-shader/) A glowing neon wave. shaders · fx - [SC Debug Overlay Pro](https://secretocho.design/lab/sc-debug-overlay-pro/) Graphs FPS, captures logs. utilities · debug - [SC Typewriter Title](https://secretocho.design/lab/sc-typewriter-title/) Type & erase rotating phrases. typography · motion ### Four platforms in four months Oct 2026 · 9 min[cat ./notes/four-platforms-in-four-months](https://secretocho.design/notes/four-platforms-in-four-months/) \[LOG\] still frames ## Before the flagships. [ls ./archive](https://secretocho.design/archive/) - 2025[Axel Properties](https://secretocho.design/work/axel-properties/) · brand, mobile design lead - 2025[SecretoCho](https://secretocho.design/lab/) · web, code 28 components - 2023–25[client identities](https://secretocho.design/archive/client-identities/) · brand 7 marks - 2023–24[Leverate](https://secretocho.design/archive/leverate/) · web, brand, mobile, print UX/UI and web designer - 2022–23[HYLA North America](https://secretocho.design/archive/hyla-north-america/) · brand, web, mobile Senior UX/UI designer - 2020–22[CPM Software](https://secretocho.design/archive/cpm-software/) · ERP, BI, mobile, desktop UX/UI designer - 2018–22[Palamut Group](https://secretocho.design/archive/palamut-group/) · mobile, web, research UX/UI designer \[MSG\] ## Hiring a design engineer? I’m open to senior design engineer roles: remote from Belgrade, or relocation with visa sponsorship. Write to me, or read the CV first. Client work stays selective, one project at a time. [sc@secretocho.design](mailto:sc@secretocho.design) [read the CV](https://secretocho.design/cv/) · [LinkedIn](https://www.linkedin.com/in/secretocho/) SecretoCho Design · Abdullah Kahvecioglu · 2026