Smart contracts and on-chain systems for DeFi teams, from London
Contracts an auditorcan actually read
Most of what goes wrong on chain was plain in the code long before it cost anyone money. Invariants first, in writing, and one test per invariant, written to break it. A keeper that runs as real infrastructure, with the stale price case decided up front. Continuum is built that way, five contracts and eight devnet markets behind a four-state oracle risk machine, pre-mainnet with audits pending.
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London, UK · Available for new projects
What actually slows DeFi and web3 teams
The keeper is always somebody's side project
The service that pushes prices, settles positions and runs liquidations is production infrastructure that gets treated as a script. It is also the thing that decides whether your protocol is solvent at three in the morning.
Oracle risk gets designed last
Staleness, confidence intervals and what the contract does when a feed stops publishing are usually handled after the maths is settled. They are the maths.
smart contracts and on-chain systems
Contracts in Rust and Anchor, written so an auditor can read them. The things that must always be true go in writing before the code, and each one gets a test that tries to break it. The keeper runs as production infrastructure, and what the contract does with a stale price is decided up front. Continuum works like this, 5 contracts and 8 devnet markets behind a 4-state oracle risk machine, pre-mainnet with audits pending.
- The invariant list and the tests for it
- Every rule the contract must always hold, written down, with a test that tries to break each one. The oracle failure states sit in the same document, so an auditor reads the intent first.
- What stays off chain, listed
- Some of what a team wants on chain belongs off it, in a keeper or a database with a signature over the record. The first pass tells you which parts.
Built one of these already. Continuum. A Solana DeFi protocol for 24/7 synthetic exposure to real-world assets.
See the full serviceSelected projects
Products I built and open-source projects I maintain. Open a project to see the work for yourself.
- 01
2026Continuum
Web3 · DeFi protocol
A Solana DeFi protocol for 24/7 synthetic exposure to real-world assets
Deposit USDC, mint matched long and short tokens at NAV, sell the leg you don't want. A constant-product invariant keeps the pair redeemable back to the deposit.
- Rust
- Anchor
- Solana
- TypeScript
- Pyth
- Next.js
- Bun
- Railway
Pre-mainnet. Devnet markets, audits pending.
Protocol · Frontend · Infra
- 5 Solana smart contracts in Rust
- 8 synthetic markets on devnet
- 4-state oracle risk machine
- Volatility-scaled fee curve
- 02
2025 →Delta Xi
E-commerce · Brand
A mathematics apparel brand on a storefront I wrote from scratch
I built the cart, checkout, product recommendations, affiliate programme and support desk, and run the infrastructure myself.
- Next.js
- React Server Components
- Stripe
- Auth.js
- Tailwind
- Umami
- Chatwoot
- Cloudflare
Founder · Engineer · Operator
- Custom checkout on Stripe + Klarna
- Server-rendered recommendation engine
- Self-hosted analytics and live chat
- 50+ STEM explainers driving organic search
See 4 more projects
- 032026
Dr Flavia Pretti Aslanian
Healthcare · Practice site
A bilingual dermatology website for a practice in Harley Street and Wimbledon
A new landing page guides patients to medical, aesthetic and surgical care. The practice edits its own content, and staff have a password-protected dictation tool in the same app.
- Next.js
- Sanity CMS
- Tailwind v4
- Radix
- Motion
- ISR
- Railway
- Cloudflare
Design · Build · Deploy
- 84 published English and Portuguese routes
- 72 treatment pages with clinic-editable content
- Custom before/after comparison UI
- Internal clinician dictation tool
- 042026
Dray
AI tools · Product website
A product website for keeping project context across AI agents
An editorial landing page introduces shared project context, shows illustrative agent workflows and explains setup and privacy ahead of beta.
Beta coming soon. The public demos illustrate the workflow; they are not live agent connections.
Design · Build
- Interactive agent-linking illustration
- Project-context walkthrough
- Setup and privacy guidance
- 05
2026Tallylamp
Open source · Browser infrastructure
A browser for AI agents that you can watch and take over
I built the browser service, dashboard, MCP server and public website. Agents use Chrome on your server while you watch the same browser live. Take control to sign in, then hand it back; saved profiles carry between sessions.
- TypeScript
- Next.js
- Chrome
- MCP
- SQLite
- Docker
- Railway
Public site at tallylamp.dev. The browser service and dashboard are self-hosted.
Creator · Engineer · Maintainer
- Live viewing and explicit human handoff
- Separate agent permissions and reusable profiles
- MIT licensed, with a Railway deploy template
- 06
2025 →CarClout
SaaS · AI content engine
A subscription app that turns a phone photo of a car into something worth posting
Upload a photo, pick a template, get the edit back a moment later. Thirteen AI models sit behind a metered credit ledger, next to a layer editor, a post scheduler and a live chat room.
- Next.js
- SurrealDB
- Auth.js
- Stripe
- fal.ai
- Cloudflare R2
- Stream.io
- Railway
Engineering · Infra · SEO
- 724 generated landing pages, all live
- 128 API routes behind one app
- 13 AI models on a metered credit ledger
- Instagram posting, scheduling and analytics
One runs on the client's own domain and one is internal to theirs, so there is nothing here of mine to show you.
- ClientJooyontechAI sales assistant, Korean and English
- ClientPHFWeb, AI and automation · private medical practices, UK
Not everything is public. A fair amount of the work sits in private repositories I cannot hand you a link to. Ask, and I will walk you through it.
Ask to see moreHow a project runs
- 01Before code
Scope
One call, then a written spec. What it does, what it deliberately does not do, and what milestone one is. You sign that off before I write a line.
- 02Early
First deploy
A narrow slice that actually works, running where it belongs. A URL you can open, a build on your phone, a job on your own servers. Real data, real hosting, no placeholder screens.
- 03Ongoing
Build in the open
Deploys land as the thing fills in, not in one drop at the end. You watch it happen. And you get to change your mind while changing it is still cheap.
- 04Handover
Yours to run
The product runs in your accounts, with the domain, hosting and documentation under your control. Source-code transfer is quoted separately; we agree what is included during scoping.
Rafael Aslanian
I got my hands on a computer at 6 and never really stopped.
Now it is decentralised finance, tokenising real-world assets and topological deep learning, then building whatever those turn into. Continuum came out of that. So did Delta Xi (δξ, an infinitesimal change in a random variable).
Bossa nova and MPB were always on at home, so I sang before I played anything. Guitar and piano came later, then jazz.
- Based
- London, UK
- Languages
- English, Portuguese; intermediate Spanish and Chinese
- Focus
- Web3, DeFi, real-world asset tokenisation
- Also
- Music
Have an idea? Tell me.
Need the audience too?
I can build the thing. Getting people to notice it is a separate job, and not mine. For that I work with Nytforge, who film, edit and put the work in front of a local audience. They are strongest with automotive and local businesses.