Senior full-stack developer with 8+ years experience. Rails, Python, Java, React — fractional dev capacity for funded startups. 10x performance improvements, month-to-month, no long-term commitment.
Fixed-price diagnostics from $1,500
N+1 query elimination, database optimization, caching strategy, and asset pipeline tuning. Most Rails apps have 2-3 quick wins that move PageSpeed scores 20-30 points.
Roadmaps from $2,500
Rails 6.1, 7.0, and 7.1 have lost security support. Upgrade to Rails 8 with Hotwire, Solid Queue, and ImportMaps. Migrate from deprecated Turbolinks and Webpacker.
Audits from $750
CSP, HSTS, and security header implementation. Dependency vulnerability scanning and patching. SOC 2 and compliance preparation for Rails applications.
Projects from $1,800
Web applications in any stack — Python/Django, Java/Spring, React/Next.js, or Rails. APIs, dashboards, internal tools, MVPs. I pick up your codebase and push features.
From $2,500/mo
Senior dev capacity without the recruiting overhead. I integrate with your team's workflow and start pushing production code within 48 hours. Month-to-month, cancel anytime.
Cybersecurity network discovery platform processing millions of device scans. Inherited slow Rails app with mounting N+1 queries and unoptimized SQL. Delivered 2x performance improvement through systematic query optimization and caching.
Built a Rails application connecting farmers with surplus produce to food banks in need. GraphQL API, ElasticSearch for location-based matching, and strict TDD throughout.
Optimized public health informatics systems including EpiTrax (disease surveillance) and health statistics applications. Rails + Python + Neo4j handling HL7/FHIR integrations for thousands of healthcare users.
Maintained Archnet at Performant Software Solutions - a Rails application hosting thousands of scanned historical architectural documents. Also contributed to their annotation studio using React, Ember, and Backbone.js microservices.
Lead management with kanban board, interaction tracking, and task management. Rails 8 API + React frontend.
Startup idea scoring across market, problem, solution, and business viability. PDF report generation with Prawn.
AI-powered cold email generator using Claude API. Website scraping, campaign management, and 3 email variations per prospect.
Template-based project generator with variable substitution and downloadable ZIP archives. Seeds React, Express, and Rails templates.
I'm Tim Dunn. I've spent 8+ years building and fixing web applications — Rails, Python, Java, React. From greenfield builds to inherited legacy apps with years of tech debt. My clients include cybersecurity platforms, public health agencies, and nonprofit startups.
I delivered a 2x performance improvement at Pwnie Express, built healthcare data pipelines (Rails + Python/Flask) at Southern Nevada Health District, and shipped production apps on deadline with zero launch-day bugs.
I work 10-20 hours per week on your codebase, integrating with your team's workflow. You get senior dev capacity without the recruiting overhead or long-term commitment. Month-to-month, cancel anytime.
For retainer clients: 24-48 hours for non-urgent issues, same-day for emergencies. US citizen, available for worldwide remote collaboration. I communicate async via Slack or your preferred tool.
Primary: Ruby on Rails, Python/Django, Java, React/Next.js. I also do one-time projects starting at $1,800 — performance fixes, feature builds, or full MVPs. No retainer required.
I've inherited plenty of legacy apps — Rails, Python, Java, you name it. First week is usually codebase audit and quick wins. I document as I go and communicate blockers early. No black boxes.
Book a free 15-minute call. I'll tell you what I'd fix first and give you a ballpark estimate. No pitch deck, no sales pressure.