React Native Developer Needed - FinTech Integrations

Senior Full-Stack React Native Developer — Supabase & Fintech API Integrations

Company: The Gold App Inc.
Project: The Gold App
Platforms: Existing iOS & Android Apps and Two Websites
Engagement: Freelance, Milestone-Based, Long-Term Potential

Project Overview

The Gold App is an established fintech platform with live applications on the Apple App Store and Google Play, two operational websites, existing backend infrastructure, and established compliance and security controls.

We need an experienced developer to maintain our platform, improve functionality, troubleshoot problems, and complete banking, payment processing, card issuing, and other financial API integrations.

THIS IS NOT A NEW APP PROJECT. We do not want our existing applications rebuilt, redesigned, or unnecessarily migrated.

PRIMARY HIRING REQUIREMENT: VERIFIED COMPLETED WORK

Proof of completed projects and professional references is mandatory.

Every bidder must provide:

* At least TWO completed, operational applications or websites with direct working links.
* Apple App Store or Google Play links where applicable.
* Specific details of their personal contributions and completed API integrations.
* At least TWO genuine professional references from previous clients, employers, or project owners, available for verification with permission.
* Evidence of successfully completed financial API or Supabase development.
* Willingness to demonstrate previous work during a live technical interview where reasonably possible.

Screenshots, mockups, unfinished projects, generic portfolios, and unverifiable claims are insufficient.

We will verify completed work, references, technical experience, and the identity of the actual developer before awarding the project.

Required Technology Stack

Strong production experience required with:

* React Native: iOS and Android development and maintenance.
* React.js: Existing website development.
* Node.js: Backend services and APIs.
* Python: Backend development and integrations.
* Supabase: PostgreSQL, authentication, Row Level Security (RLS), Edge Functions, storage, and database security.
* Plaid: Banking connectivity and financial APIs.
* REST APIs, JSON, OAuth 2.0, Webhooks: Secure integrations and transaction processing.
* Git/GitHub: Version control, repositories, and deployment.
* Cloud Infrastructure: Databases, hosting, security, and production environments.

Firebase, AWS, CI/CD, and app store deployment experience are advantageous.

Named Financial APIs & Integrations

Our development involves existing systems and approved or prospective integrations.

Banking & Financial Connectivity

* Plaid: Existing banking connectivity, account linking, and verification.
* Yodlee: Financial account aggregation where applicable.
* Banking APIs: ACH, account verification, transfers, payouts, and reconciliation.

Payments & Merchant Processing

* Finix: Merchant processing, payment APIs, transactions, and settlements.
* Kurv / AltruPay: Merchant processing and gateway integration.
* Authorize.net: Payment gateway functionality where applicable.
* Additional approved payment processors and financial providers.

Precious Metals & Custody

* StoneX Precious Metals: Supplier connectivity where available.
* International Depository Services (IDS): Custody and operational connectivity where available.
* Precious metals pricing APIs, inventory, purchasing, sales, and order management systems.

Identity & Financial Services

* Existing KYC/AML and customer verification workflows.
* AeraPass-related functionality where applicable.
* Additional approved banking, card issuing, authentication, and financial APIs.

Integrations are subject to provider availability, agreements, underwriting, and company approval.

Development Responsibilities

* Maintain existing React Native mobile apps and React.js websites.
* Develop and troubleshoot Node.js and Python backend services.
* Maintain Supabase PostgreSQL, RLS, authentication, Edge Functions, and database integrations.
* Review existing code, architecture, repositories, and APIs.
* Implement banking, payment processing, card issuing, and financial APIs.
* Maintain and expand Plaid functionality.
* Integrate approved pricing, supplier, inventory, and custody services.
* Develop secure REST APIs, OAuth authentication, and webhooks.
* Maintain data synchronization across apps, websites, databases, and providers.
* Resolve API failures, duplicate transactions, database issues, and settlement discrepancies.
* Support iOS and Android releases.
* Deliver tested, documented, secure, maintainable code.

All existing operational functionality must be preserved.

Regulatory Compliance & Security

The Gold App already operates within an established regulatory compliance and security framework.

Developers must preserve existing authentication, authorization, transaction monitoring, and compliance-related controls.

Requirements include:

* Secure APIs, encryption, webhook verification, and credential management.
* Supabase RLS protections and restricted database permissions.
* Financial transaction integrity, audit logging, and data protection.
* Approval before modifying compliance-sensitive workflows.
* Security testing, code review, and controlled deployments.
* Identification of potential compliance or security impacts before implementation.

Developers implement approved technical requirements and are not independently responsible for determining regulatory obligations.

Identity Verification & Contractor Protection

The person performing the development MUST be verified. Unidentified substitute developers are prohibited.

Selected bidders must agree to:

* Identity verification and a live video interview.
* Verification of previous completed projects and references.
* NDA and intellectual property assignment agreements.
* Company-controlled GitHub repositories and development environments.
* Restricted access, MFA, and secure credential handling.
* No subcontracting or additional developers without written approval.
* No disclosure of proprietary code or sensitive information to external AI tools without authorization.
* Protection of source code, customer information, credentials, and financial data.
* Prompt security incident reporting and return or deletion of company materials upon completion.

Unrestricted production access, live banking credentials, and sensitive customer information will not be provided by default. Sandbox environments and limited permissions will be used where practical.

English Proficiency

VERY HIGH SPOKEN AND WRITTEN ENGLISH PROFICIENCY IS MANDATORY.

Developers must communicate clearly during live video calls, explain technical work, understand instructions, produce English documentation, and provide professional progress updates.

English proficiency will be evaluated during interviews.

Mandatory Bidder Screening

All 12 questions must be answered. Generic or incomplete bids will be rejected.

1. Provide links to TWO completed, operational applications or websites you personally developed. Describe your contributions.
2. Provide TWO professional references who can verify your work, with contact information or an agreed introduction method.
3. Which financial APIs have you personally integrated? Include experience with Plaid, Yodlee, Finix, Authorize.net, banking, card issuing, or comparable services.
4. Describe one completed financial API integration, including backend technology, authentication, webhooks, and production functionality.
5. Explain your Supabase experience with PostgreSQL, RLS, authentication, Edge Functions, and database security.
6. Can you independently handle React Native, React.js, Node.js, Python, Supabase, and production deployments? Identify limitations.
7. How do you prevent duplicate transactions, verify webhooks, handle API failures, and reconcile payments?
8. How would you add a financial API to our existing platform without disrupting operational systems?
9. Describe your experience with fintech security, PCI DSS-related controls, KYC/AML workflows, or audit logging.
10. Will you personally perform the work, complete identity verification, and participate in a live technical interview?
11. Confirm your spoken and written English proficiency and willingness to sign NDA/IP agreements and follow restricted access requirements.
12. Will you complete a small, paid technical assessment before receiving larger assignments?

Clarification Board

Bidders asking questions on the public clarification board may not be considered for hiring. Review the complete listing before bidding. Confidential technical questions can be discussed privately with shortlisted candidates.

Working Arrangement

Freelance, milestone-based development with potential ongoing assignments. Deliverables, timelines, and pricing will be agreed upon before work begins.

We prefer individual developers who personally complete the work and communicate directly.

Generic AI-generated bids, copied portfolios, intermediaries, unverifiable experience, and unnecessary rebuilding are unacceptable.

Bid Submission Instructions

BEGIN YOUR BID WITH: GOLD API READY

Your bid MUST include:

* Two completed, operational projects with direct links.
* Two verifiable professional references.
* Personally completed financial API integration examples.
* Answers to all 12 screening questions.
* Supabase and full-stack experience.
* Confirmation of very high English proficiency.
* Agreement to identity verification and a live interview.
* Availability, start date, and hourly rate or milestone pricing.

COMPLETED WORK, VERIFIED REFERENCES, IDENTITY VERIFICATION, AND VERY HIGH ENGLISH PROFICIENCY ARE NON-NEGOTIABLE REQUIREMENTS.