WHO I AM

Hey, I'm Saleh.

Building backend systems that stay correct when real money moves.

Senior Backend Engineer: Ruby on Rails, payment infrastructure, subscription billing, and the PostgreSQL performance work that keeps it all fast. Rails core contributor.

IDEMPOTENCYRECONCILIATION WEBHOOKSPOSTGRESQL RAILS CORE
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RAILS CORE CONTRIBUTOR TECHNICAL WRITER POSTGRESQL TUNER MENTOR
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NAMESALEH SALEM ALHADDAD
ROLESENIOR BACKEND ENGINEER
STACKRAILS · POSTGRESQL · AWS
DOMAINPAYMENTS & BILLING
EXPERIENCE8+ YEARS
AVAILABILITYREMOTE | HYBRID | ON-SITE
BASEHADRAMOUT, YEMEN · GMT+3
SA·RAILS·PGSQL·SQS·CHARGEBEE
SELECTED WORK JISR · SUBSCRIPTION SAAS
Virtual IBAN & Bank Transfer Rails
Per-organization account provisioning across two banking providers: idempotent issuance, graduated retries with backoff, async fallback.
FINTECHIDEMPOTENCYSQS
Payment Retry & Idempotency
Exponential backoff on Chargebee payments, safe to retry by construction: no double charges, ever.
BILLINGCHARGEBEE
Dunning & Payment Recovery
Failed-payment pipeline: batched status reconciliation, notifications, automated offline-billing fallback.
PAYMENTSRECOVERY
Subscription Churn-Save Funnel
Tier-based retention offers applied transactionally, one offer per account, with a clean revert path.
GROWTHRETENTION
Event-Sourced Audit Log
Subscription history with jsonb snapshots, async SQS writes, and partial composite indexes.
POSTGRESQLEVENT SOURCING
CRM & Analytics Integrations
Bidirectional HubSpot sync and a Segment pipeline delivered over SQS with scheduled reconciliation.
HUBSPOTSEGMENT
OPEN SOURCE

Fixed where.associated in Rails core.

Join types in complex ActiveRecord queries now stay what you wrote: predictable SQL for every app on Rails.

PR #51078 · MERGED
WRITING MEDIUM
Optimizing Ruby on Rails apps for high performance
Finding database bottlenecks, and what to do about them. PERFORMANCE How to benchmark your Ruby code
Measuring before optimizing, with Ruby's own tools. TESTING TOTP with a Ruby on Rails API
Time-based one-time passwords, end to end. SECURITY
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