Senior Backend Engineer

Sean Floyd

I help scaling SaaS companies reduce Rails infrastructure costs 30-50% through performance optimization. From 98% performance improvements to €160k annual savings, I deliver measurable impact via remote B2B consulting.

Backend engineer specializing in Rails performance optimization and cost reduction. 9 years experience with PostgreSQL, Redis, Sidekiq, API architecture, and CI/CD optimization. Proven track record scaling multi-tenant SaaS platforms. M.Sc. in ML/distributed systems. Available for remote B2B consulting.

QUICK STATS

9 years
Engineering Experience
17+ countries
Worked remotely from
€160k saved
Annual infrastructure costs
Ruby + Rails
Core expertise

TRACK RECORD

Real Results at Hivebrite

3+ years scaling a multi-tenant SaaS platform serving 600+ communities and millions of users. Reduced annual infrastructure costs by €160K while supporting 4x engineering team growth from 9 to 40 developers—preventing customer churn through performance optimization and maintaining delivery velocity through improved tooling.

98%
Performance Improvement

Architected data export system using Sidekiq Batch processing and database optimization (PostgreSQL query improvements, chunking) reducing processing time from hours to minutes for communities with 1M+ users, preventing critical customer churn

€160k
Annual Cost Reduction (8% of infrastructure)

CI/CD pipeline optimization through Buildkite migration. Additional infrastructure improvements: 66% faster background job processing (Sidekiq optimization) and Kubernetes autoscaling reducing compute costs

50%
Faster Deployments

Cut CI/CD build times in half (Buildkite optimization, Docker layer caching) while doubling deployment frequency, enabling faster feature delivery and iteration

75%
Faster Onboarding

Created CLI tooling (hivecli) automating Docker setup, database seeding, and local environment configuration, reducing developer setup from days to hours and supporting team growth from 9 to 40 engineers

"Every optimization tells a story. The 98% improvement meant clients could export their data on-demand instead of waiting overnight. The €160k savings funded new features. The faster builds meant developers shipped code confidently. I don't just write code—I solve real problems."

EXPERTISE

What I Bring

Ruby/Rails Expertise

9+ years production Rails experience (Rails 3-7) with PostgreSQL, Redis, Elasticsearch. Including 9-year volunteer platform and 3+ years scaling multi-tenant SaaS with background jobs (Sidekiq Pro), REST APIs (Grape), gRPC microservices, and database optimization. Architected versioned API infrastructure with OAuth2 authentication. Led Ruby 3 and Rails 7 migration and large-scale Rails modularization (Packwerk, engines-to-packs migration). Contributor to Rails core and Ruby 3 ecosystem.

Infrastructure Optimization

Docker, Kubernetes, web servers (Puma, Nginx), CI/CD pipelines (Buildkite, GitHub Actions, CircleCI, Travis CI), autoscaling strategies. Proven track record of reducing costs while improving performance through monitoring (Datadog, Sentry, OpenTelemetry) and optimization.

Developer Productivity

Building tools that make teams more effective. From CLI utilities to automated workflows, testing (RSpec, TDD), and test reliability improvements (fixing flaky tests, improving CI stability), I eliminate friction and improve developer experience.

Global Remote Work

Grew up in diplomatic and international education environments across 6 countries (India, France, Germany, Canada, South Korea, Morocco) before high school, developing deep cross-cultural fluency. 7 years fully remote from 17+ countries across Asia, Europe, and Americas. Expert at async communication, documentation, and self-directed work across time zones.

Bilingual Communication

Native fluency in English and French. Canadian/French dual citizen with experience communicating across cultures and navigating international business contexts.

Technical Leadership & Mentoring

Led engineering team growth from 9 to 40 developers. Developed technical interview processes, conducted training sessions, and provided architectural guidance. Experience communicating technical decisions to executives and stakeholders.

Ruby Rails Grape API gRPC Sinatra Python PostgreSQL Redis SQL Docker Kubernetes Dokku Nginx CI/CD Buildkite GitHub Actions CircleCI Travis CI REST APIs API Versioning OAuth2 OpenAPI/Swagger Performance Optimization Background Jobs Sidekiq Sidekiq Pro Puma RabbitMQ RSpec TDD Packwerk Rails Engines Stimulus Webpack Node.js JavaScript Selenium OpenTelemetry LLM Integrations Elasticsearch Datadog Sentry AWS S3

PORTFOLIO

Notable Work

API Architecture (Hivebrite)

Architected versioned REST API infrastructure supporting third-party integrations. Built API version management system with Hydra OAuth2 authentication, OpenAPI/Swagger documentation (Redocly), rate limiting (Rack::Attack), and automated changelog generation. Separated 500+ monolith routes into dedicated API pods.

Rails & Ruby Ecosystem

Discovered performance bottleneck during production profiling and contributed fix to Rails ActiveSupport achieving 20x-670x speedup. Contributed Rails 7 compatibility fixes to stateful_enum, ruby-activerecord-opentracing, and jaeger-client-ruby.

View Rails PR →

Rails Async Migrations (Hivebrite)

Reimplemented async migrations system for zero-downtime deployments at scale. Enhanced open-source gem with Slack notifications and improved error handling. Deployed to production serving millions of users across 600+ communities.

View fork →

Jazzify Platform

Built and maintained volunteer management platform for Ottawa Jazz Festival for 9 years. Full-stack Rails app handling thousands of applications with complete CI/CD (CircleCI→Dokku), monitoring, and security infrastructure. Managed production deployment and operations.

View archived site →

Weather MCP Server

Built Model Context Protocol server integrating Canadian government weather data for AI agents. Demonstrates capability to build AI-native tooling and LLM integrations.

View project →

still_active Gem

RubyGem for analyzing dependency maintenance status. Helps teams identify abandoned dependencies and manage technical debt.

View gem →

ML Research: Stream Processing

Published research at ECML PKDD achieving 160x performance improvement in partially-labeled data stream processing. M.Sc. thesis work in machine learning systems.

View publication →

APPROACH

How I Work

1

Pragmatic over Perfect

Find the simplest solution that solves the actual problem. No over-engineering, no premature optimization.

2

Data-Driven Decisions

Instrument everything. Use metrics and observability to guide optimization, not gut feelings.

3

Document the Why

Write clear documentation explaining decisions and trade-offs. Make systems understandable for future maintainers.

4

Gradual Improvements

Prefer measured, incremental changes over risky big-bang rewrites. Ship value continuously.

5

Impact-Focused

Every technical decision should connect to business value or user experience improvement.

LOOKING FOR

Ideal Engagement

Seeking remote B2B consulting with scaling SaaS companies facing performance or cost challenges. Modern Rails applications (Rails 7+)—not legacy modernization projects. Flexible engagement structures: project-based, retainer arrangements, or longer-term embedded consulting.

Type of Work

  • Infrastructure cost optimization and performance engineering (Rails, PostgreSQL, Redis, Sidekiq)
  • API architecture and design (versioning strategies, OAuth2, OpenAPI, third-party integrations)
  • Scaling challenges (database optimization, background jobs, REST/gRPC APIs, caching)
  • AI/LLM feature development and integrations (Python, REST/gRPC APIs)
  • Developer productivity tooling and CI/CD improvements (Docker, Buildkite, GitHub Actions)

Not a fit for: Legacy Rails modernization (Rails 3-6 upgrades), traditional employment (W-2/CDI), on-site office requirements

Company Fit

  • Scaling SaaS companies (Series A-C) with infrastructure challenges
  • Modern Rails applications (Rails 7+) facing performance or cost issues
  • Remote B2B consulting (flexible on hours and duration for compelling work)
  • Open to EMEA, Americas, or APAC-based companies

Why Contract?

I deliver focused infrastructure optimization without full-time employment overhead. Ideal for companies with specific performance or cost challenges requiring senior-level expertise. Work thrives when I have location flexibility—7 years remote from 17+ countries proves this works. Canadian/French dual citizen comfortable with global teams.

Let's Build Together

Working on interesting technical challenges with a great team? Let's talk about how I can help you ship better software, faster.