Abdelwahab Mahmoud
Senior Software Engineer · Full-stack & Platform
I build and run production systems end to end, from React in the browser to AWS underneath. Most recently: the LLM engine and cloud platform behind an AI translation product that peaked at ~100K requests an hour.
About
I studied geophysics, then started in software in 2018 on Extreme Programming teams: pair programming, the test written first, small slices shipped continuously. Most of how I work still comes from there.
I work across the stack: React, Next.js and React Native in the product, Rails and Node.js services behind it, and the AWS platform and databases underneath. The last few years leaned toward the platform half: autoscaling, database load and LLM provider failover.
I like owning a system from the architecture decision to the incident review. When production breaks, I write down what is verified and what is only inferred before I change anything. The write-ups on this site come out of that habit.
Experience
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AI translation platform (under NDA)
Senior Software Engineer
Scaled AI translation to 500K jobs an hour at peak without killing a job mid-run
The product was an AI translation platform that ran LLM jobs on AWS. I did full-stack product work in Rails and React and owned the AWS platform under it. Load sat at ~5K jobs an hour and peaked at 500K. Jobs could run for hours, and the default ECS autoscaling stopped busy tasks on scale-in, so every peak cost work in progress. I migrated the product onto ECS Fargate with Terraform and replaced the scaler with a queue-depth autoscaler on Lambda, deployment state in DynamoDB, that drains a task before stopping it. The fleet handled ~100K requests an hour at peak across background processing and LLM inference.
Write-up: Scaling ECS workers on queue depth without killing long jobs →
- Built the multi-provider translation LLM engine with the team (Bedrock, OpenAI, Gemini): fallback chains, JSON repair and rate-limit retries kept translations flowing when a provider degraded.
- Cleared Aurora MySQL's worst-query backlog query by query: rewritten plans, covering indexes and restructured hot reads, until CPU pressure stopped turning into incidents.
- Fixed lock contention under concurrent writes: exclusive advisory locks on hot paths, batch-processing rewrites for load management, and connection-pool tuning after autoscaling exposed pooling contention on the shared database.
Show 5 more
- Built the MCP server the team's agents ran behind, exposing live databases, logs and selected APIs through authenticated, monitored access. It became the team's standard agent integration path.
- Owned credits and billing correctness for a metered LLM product, and replaced scattered permission checks with one authorization architecture.
- Owned an agentic triage platform that handled first-line incident and support inquiries, cutting Mean Time To Resolve.
- Owned the GitLab CI/CD pipelines: build, e2e test, SAST and deploy gates for every service in the product.
- Kept public APIs backwards compatible across releases with deprecation paths and contract tests.
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Dailymealz Senior Software Engineer
Pulled fulfillment out of a PHP monolith while 100K daily users kept ordering
Dailymealz runs meal subscriptions across Saudi Arabia, and every order moves through kitchen, driver and delivery in real time. I built the order service that pushes that status to mobile and web clients over Node.js and Socket.IO, then took the fulfillment component out of the PHP/Laravel monolith behind it. A full rewrite was off the table: a team of six could not freeze features for months to run two partially consistent systems. So fulfillment came out piece by piece, as a standalone service passing state changes over AWS SQS behind a REST API contract.
Dailymealz Write-up: Extracting fulfillment from a PHP monolith over SQS →
- Cut Mean Time To Resolve by 30% by instrumenting order, driver and kitchen flows with Datadog and OpenTelemetry.
- Served hot order state from Redis in a write-behind cache with MySQL behind it, keeping status fan-out off the transactional path.
- Migrated the real-time order service from JavaScript to TypeScript, so event and message payload mismatches failed at compile time instead of in front of customers.
- Led a team of five building a driver location check-in system in the React Native driver app: planning, reviews and pairing.
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Nformacy Full-Stack Developer
Took a two-sided marketplace from empty repo to beta launch
Nformacy connects business advisors with companies that need their expertise. I built it full stack in React and Ruby on Rails, from the first MVP to the beta launch, along with the cloud infrastructure and deploy pipelines it ran on.
Nformacy Write-up: Building a booking marketplace from empty repo to beta →
- Led full-stack features from requirements to deployment, and moved the web apps to a SaaS model.
- Built mentor calendar booking on Zoom, ClickUp and calendar integrations.
- Wrote BDD tests and owned the CI/CD pipelines.
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DevSquads (formerly Fikr Labs) Software Engineer
Built Shapa's mobile app and backend test-first, and mentored teams adopting XP
DevSquads started as Fikr Labs, a Cairo venture studio, and became an agile consultancy that takes Extreme Programming seriously: TDD, pair programming and continuous delivery. I delivered products for its international clients. For Shapa, a US health product built around a numberless smart scale and a behavior change program, I built the mobile app and the backend behind it in React Native, Node.js and Java Spring.
- Built software in self-organizing Extreme Programming teams with TDD, thin vertical slices and test-covered refactoring of legacy code, across React Native, Ruby on Rails, Java Spring and React.
- Mentored teams adopting XP and Agile practices: pairing, code review discipline and iterative planning.
Writing
Handling backpressure in Node.js streams
A Node.js stream says slow down with one boolean. Ignore it and a single stalled client parks 200 MiB in your process. Here is how the signal travels.
Case studyBuilding a booking marketplace from empty repo to beta
A booking marketplace from empty repo to beta. Why CI came in week one, and why double booking is a database problem, not a UI check.
NotePreventing stock overselling in Redis with Lua scripts
Every Redis command is atomic. The check-then-write your app wraps around them is not, and that gap is how 100 units become 121 orders.
Open source
- ecs-drain-scaler Backlog-driven scaling for queue workers on ECS Fargate, with a worker protocol that keeps scale-in and deploys from killing a task mid-job. Author · Design stage: ADRs and the scaling policy in Go, with tests.
- focusflow Offline-first daily planner and focus timer, with an optional local agent that proposes tasks from open tickets, merge requests and parked branches. Author · Built for my own working day.
- handoff-mcp-server MCP server that saves an AI coding agent's task state and loads it back in the next session as a short briefing. Author · A briefing, not a transcript: one to two thousand tokens.
- egy-finance-radar Research tool for the Egyptian Exchange: positions in Postgres, fundamentals, technical signals and dated recommendations. Author · Every number carries where it came from.
Skills
Languages
- PHP
- TypeScript
- JavaScript
- Go
- Ruby
- Java (Spring)
- Python
- SQL
Backend
- Ruby on Rails
- Node.js
- REST API design
- service-oriented architecture
- SQS
- Kafka
Frontend
- Next.js
- React
- Redux
- Hotwire (Turbo & Stimulus)
- React Native
- Tailwind CSS
AI & LLM
- AWS Bedrock
- OpenAI
- Gemini
- agentic workflows
- Claude Agent SDK
- MCP
- Langfuse
- evals
Cloud & Infrastructure
- AWS (ECS Fargate, Lambda, SQS, Step Functions, CloudWatch, S3, IAM)
- Kubernetes
- Terraform
- Docker
- GitHub Actions
- GitLab CI
Observability
- Datadog
- OpenTelemetry
- AWS CloudWatch
- Langfuse tracing
Databases
- PostgreSQL
- MySQL
- Aurora
- Redis
- DynamoDB
- ClickHouse
Testing
- TDD
- Spec-driven development
- RSpec
- Capybara
- Playwright
- Cypress
- Jest
- VCR
Compatibility & i18n
- backwards compatibility
- deprecation paths
- contract tests
- i18n
Spoken Languages
- English
- Arabic (native)
Education
Faculty of Science Cairo University
BSc in Geophysics
Contact
Contact me
Hiring for a senior full-stack or platform role, or stuck on a production problem? Email me.
[email protected]