QA Engineer/Test Lead - MVP Trading Platform at Wagglyn, London Area, £Contractor Rate

Role Summary

Wagglyn is looking for an experienced QA Engineer / Test Lead to work with the existing engineering team on the testing and release readiness of its MVP trading platform.

This is a hands-on contract role for someone who has tested complex financial or real-time systems before. It is not a generic web QA role and not a manual-testing-only role.

Scope

The contractor will help define and execute the QA process across the front end, backend services, market data, execution flows, deployment environments and operational readiness.

The role involves working with engineering, product and stakeholders to make sure releases are testable, repeatable and safe to promote through UAT and production-like environments. QA here is about proving the system behaves safely when data is live, services reconnect, orders are sent, risk state changes and deployments happen.

Profile

·      Hands-on QA engineer who has tested complex financial or real-time systems

·      Practical, structured, and comfortable working directly with engineers in a fast-moving environment

·      Comfortable building the QA process while delivery continues, rather than relying on a fully mature QA function

·      Strong on edge cases, failure modes, and operational behaviour, not just checking screens

·      Not suitable for a generic manual tester with only simple web-app experience

Immediate Priorities

·      Establish a QA test plan for the MVP trading dashboard

·      Create a smoke test checklist for each deployment

·      Define the regression pack for core trading flows

·      Validate market data, strategy, execution, and risk state visibility

·      Test UI reconnect, refresh, stale data, and service restart behaviour

·      Verify traceability across order and execution events

·      Support UAT readiness and evidence capture

·      Help engineering identify gaps before client-facing demos or releases

Core Responsibilities

·      Own the QA process for MVP releases

·      Define test plans for each release, feature, and environment

·    Build and maintain regression coverage across the UI, APIs, backend services, and key trading workflows

·   Validate end-to-end flows from market data through order creation, execution, risk state, and dashboard visibility

·      Verify API behaviour, data contracts, error handling, and edge cases

·      Support UAT with clear test scripts, evidence, and issue tracking

·      Work with developers to make features testable before they reach UAT

·      Create automated tests where appropriate — API, regression, smoke, and deployment verification

·      Help define release entry and exit criteria

·      Track defects clearly, with reproduction steps, expected and actual behaviour, evidence, and severity

·   Validate deployment outcomes across environments, including service health, configuration, connectivity, and rollback readiness

·      Contribute to runbooks and operational test checklists

Key Areas to Test

Trading Dashboard

·      Market data health and staleness indicators

·      Strategy, order, and execution status

·      Risk and limit-breach visibility

·      UI reconnect and stale-state handling

·      Correct display of backend state after refresh or reconnect

Market Data

·      Live data visibility and feed health

·      Gap and staleness detection

·      Handling of feed disconnects, delayed data, malformed messages, or missing data

Execution Flows

·      Order submission and lifecycle handling

·      Acknowledgements, fills, rejects, cancels, and disconnect behaviour

·      Duplicate order prevention

·      Session status visibility

·      Audit trail for order and execution events

Risk and Control

·      Risk state shown correctly in the dashboard

·      Halt and limit-breach behaviour

·      Strategy enable/disable and operator control state

·      Safe behaviour after service restart, reconnect, or partial outage

Deployment and Environment Readiness

·      Smoke testing after deployment

·      Service status and environment configuration checks

·      API connectivity and UI/backend compatibility

·      Database connectivity where relevant

·      Rollback and recovery validation

·      UAT test evidence and release notes

Technology Stack

Not the primary developer in all of these, but should be comfortable testing systems built with them.

·      Linux

·      GitHub / GitHub Actions

·      REST APIs and real-time feeds (WebSocket / SSE)

·      Financial messaging or FIX protocol testing

·      SQL and/or time-series databases

·      Rust services

·      TypeScript / React / Next.js front end

·      CI/CD pipelines

·      Docker / systemd-based service deployments

·      Log analysis using service and structured application logs

·      API testing tools such as Postman, Bruno, or curl

·      Test automation tools such as Playwright, Cypress, pytest, or JUnit

Required Experience

·      Strong QA experience on complex backend or trading-platform systems

·      Writing practical test plans and regression packs

·      Testing APIs, asynchronous systems, and real-time data flows

·      Working with production-like UAT environments

·     Reading logs to isolate whether an issue is front end, backend, data, configuration, deployment, or environment related

·      Good understanding of defect severity and release risk

·      Comfortable working directly with developers rather than as a separate test silo

·      Creating clear test evidence for stakeholders

Preferred Experience

·      Trading systems, OMS, EMS, FIX, market data, or financial platforms

·      Low-latency or event-driven systems

·      Real-time dashboards and monitoring interfaces

·      Risk controls, kill switches, order lifecycle testing, or audit traceability

·      Automated API and UI regression testing

·      Testing systems deployed across multiple environments

·      UAT coordination for external users or clients

Success Criteria

·      Releases have clear test coverage and pass/fail evidence

·      UAT issues are reproducible, prioritised, and clearly tracked

·      The team has a repeatable deployment smoke test

·      Core trading workflows are covered by regression tests

·      Dashboard state can be trusted by operators

·      Critical safety behaviours are tested, not assumed

·      QA improves delivery speed by catching issues early

Contract Structure

·      Full-time contractor

·      Rolling fixed-term arrangement

·      Immediate start preferred

·      Outside IR35

·      Strong preference for candidates who are immediately available

About Wagglyn

Wagglyn is a bespoke FX consultancy mandated by a single-family office to develop and implement a systematic total return strategy in foreign exchange markets.

We are building an institutional-grade algorithmic FX trading capability, combining quantitative research and high-performance engineering.