Daniel Chen

Daniel Chen · Independent fintech engineer

Fintech products, from architecture to launch.

I work directly with founders, brokers and prop firms as a hands-on technical partner. MetaTrader 5 integrations, trading platforms, payment and wallet systems: one senior engineer who owns the architecture, the backend, the front end and the deployment.

Discuss your projectSee the engineering work

Taking on selected engagements · Remote from Kuala Lumpur (GMT+8)

Experience from

  • CFI Financial
  • Appnovation
  • Tencent
  • TradersFlow
  • SolveMY

What I help build

One engineer who owns the hard parts.

Most of the risk in a financial product sits where money, trading data and third-party systems meet. That is where I work, and I stay hands-on from the first architecture sketch to production.

Also available

Selected work

Evidence, labelled honestly.

Production systems from jobs and contracts, and my own product. Every card says which is which.

  • Built in a full-time job
  • Freelance contract
  • My own product

All case studies

How we can work together

Start small. Commit when it works.

Every engagement starts with a written scope. You know what you are getting, what it costs and what is left out before any work begins.

  1. 01Fixed fee · 1 to 3 weeks

    Technical discovery sprint

    I review your requirements, existing code and third-party access, then deliver a written architecture, a feasibility and risk report and a milestone plan. Yours to keep, whoever builds it.

  2. 02Paid by milestone

    Fixed-scope MVP build

    A defined first release, built in milestones on a staging environment you can use throughout. You pay for delivered milestones, not for hours.

  3. 03Monthly

    Founding engineer contract

    I join as your hands-on technical owner: architecture, backend, front end, infrastructure and releases, working directly with you.

  4. 04Part-time · monthly

    Fractional technical lead

    You already have a developer or a small team. I own the architecture and the risky parts, review the work and keep delivery honest.

I quote each engagement in USD after a first call. I work from Malaysia with no agency layer, so the budget goes into engineering, not account management. I price on scope and responsibility, and I am not the cheapest option.

  • You work with the person doing the work
  • Written scope and milestones
  • Source code, access and documentation handed over
  • NDA on request

Now · full-time role

Senior Backend Engineer at CFI Financial.

A crypto trading platform and payment integrations at an online multi-asset broker. Two databases, one back office, one client portal, and RabbitMQ in between.

Since July 2026

Read the case study

  1. Payments

    Three wallets, live in production.

    Apple Pay, Google Pay and Benefit as separate Checkout.com deposit methods. Then I wrote the guide nobody had: running deposits and refunds end to end on a laptop, traps included.

  2. Debugging

    Bugs traced to the exact line, on both sides.

    An HTTP 500 on trades: correlation id, Loki, duplicate asset pairs, deterministic resolution on every order path. A KYC edit that never reached the portal: dropped at the producer and the consumer, proven on pinned versions before a line changed.

  3. Building

    Endpoints with permissions down to the field.

    Paginated, filterable lists and CSV/PDF exports behind field-level access control for the maker-checker cancellation flow. 8-decimal precision for crypto amounts across APIs, models and ACL. Braze events for first deposits.

  4. Shipping

    Learning the lead’s side of the job by doing it.

    Splitting stories into sub-tasks by layer, sequencing shared-library releases with tags and consumer pins, writing deploy order and Notes for QA, and demoing in sprint review. 38 PRs merged through lead review.

By the numbers

Wallet payment methods in productionApple Pay · Google Pay · Benefit
3
Breach-check cycle on live MT5 accountsProp-firm risk monitor
~5 s
REST endpoints in one Go APISolveMY, 31 domain services
235
Go test functionsSolveMY backend
1,006

Work history

Experience at a glance.

Where the experience comes from. Each row says whether it was a full-time job, a freelance contract or my own product.

  • Jul 2026 to PresentFull-timeCFI FinancialSenior Backend Engineer
  • Jan 2026 to PresentOwn productSolveMYCTO and hands-on engineering lead
  • Nov 2025 to Jun 2026FreelanceTradersFlow (TRFC)Full-Stack Engineer
  • Sep 2025 to Aug 2026Full-timeAppnovationFull-Stack Developer
  • Sep 2024 to Sep 2025Full-timeTencentOverseas Lead Developer, AMS
  • Jun 2023 to Sep 2024Full-timeCorebase TechnologiesFull-Stack Developer

Full work history

Notes

Technical write-ups from building trading platforms, payment systems and products. Each one says whether it comes from production or is a design proposal.

All notes