
Closed
Posted
We are hiring an experienced backend-focused full-stack developer to work on a live, production SaaS platform. The platform handles complex, regulated workflows with multiple external API integrations — both REST and SOAP-based, including certificate-authenticated and OAuth2-secured endpoints. This is not a startup greenfield project. The platform is already in production. You will be working inside an existing codebase with real users, not building from scratch. What you'll be working on: • Migrating a legacy database abstraction layer to native [login to view URL] (incremental, tested, phased — not a big-bang rewrite) • Adding a PostgreSQL-backed background job worker to handle long-running external API calls asynchronously • Hardening workflow state management — ensuring all status transitions are guarded and audited centrally • Structured logging improvements (pino is already set up) • Supporting and extending external REST/SOAP API integrations • Backend improvements to document processing and confidence-scoring features • Admin/operator tooling — queues, dashboards, review surfaces Required skills — must have in production, not just tutorials: • TypeScript — strict mode, Zod validation, discriminated unions • [login to view URL] 14 App Router — Route Handlers, Server Components, auth patterns • PostgreSQL — schema design, transactions, migrations, partial indexes, concurrency • [login to view URL] — native tagged template API • External API integration — SOAP/XML, OAuth2 machine-to-machine, or certificate-based APIs • Async backend patterns — idempotency, retry/backoff, dead-letter handling Strongly preferred: Background in regulated or compliance-critical software; SOAP/XML signing experience; pg-boss or BullMQ; structured observability (pino/OpenTelemetry); multi-jurisdiction integration architecture What you must NOT do without written approval: redesign the stack, introduce ORMs (no Prisma/Drizzle), change workflow lifecycle semantics, alter submission payload structures, modify auth or certificate handling, rewrite working modules Deliverable format: Git PR per task with clear commit history. Per-task technical note: what changed, why, migration impact, rollback plan, test coverage, known limits. For API work: request/response mapping, retry behaviour, error cases handled. To apply, include: 1. 2–4 projects that are directly comparable — stack, your role, production scale 2. Specific experience with [login to view URL] App Router backend development 3. How you approach idempotency in external API submission pipelines 4. One example of a risky production refactor you shipped safely, with the risk you managed 5. Your timezone and weekly availability If you have worked in regulated, auditable, or compliance-critical backend systems and understand what it means when bugs have financial consequences — we want to hear from you first.
Project ID: 40391223
168 proposals
Remote project
Active 21 secs ago
Set your budget and timeframe
Get paid for your work
Outline your proposal
It's free to sign up and bid on jobs

Staines-upon-thames, United Kingdom
Payment method verified
Member since Apr 30, 2021
£750-1500 GBP
£20-250 GBP
£20-250 GBP
£750-1500 GBP
£20-250 GBP
₹400-750 INR / hour
$250-750 USD
$250-750 USD
$250-750 USD
$250-750 USD
$30-250 USD
$30-250 USD
$2-8 USD / hour
$250-750 USD
$30-250 USD
$250-750 USD
₹750-1250 INR / hour
₹10000-15000 INR
$250-750 USD
₹1500-12500 INR
₹100-400 INR / hour
$250-750 USD
₹250000-500000 INR
₹1500-12500 INR
₹1250-2500 INR / hour