Steve Johnson
Verified Expert in Engineering
System Design Developer
San Francisco, CA, United States
Toptal member since May 13, 2022
Steve has worked in tech for 10 years, with 8 years of full-stack startup engineering experience. He has created AI, education, recruiting, bike-sharing, marketing, and sales software that millions of people have used. Steve loves delivering digital products that unlock value and reduce costs.
Portfolio
Experience
- System Design - 11 years
- TypeScript - 8 years
- Full-stack Development - 8 years
- MVP Design - 6 years
- CTO - 4 years
- Fractional CTO - 4 years
- Supabase - 3 years
- Next.js - 3 years
Work Experience
CTO | Co-founder
Bosmos
- Built a full-stack application enabling freelance matchmaking between sellers and buyers.
- Reached 1,000 MAU and $40,000 ($120,000 annual projected) revenue.
- Built chat, file, escrow, invoicing, fraud systems, and more.
CTO | Co-founder
YourStory
- Built a full web stack delivering AI-powered classroom lessons.
- Reached 10,000 MAU, 50,000 ARR, 100,000 fundraised (nine million cap).
- Built classroom management systems, creations, libraries, personal adaptations, visual aids, and more.
CTO | Co-founder
BeFluent
- Built web, Android, and iOS applications for AI-powered business English language learning.
- Developed AI chat and AI learning exercises tailored to user interests and goals.
- Built company internal tools so that company curriculum developers could tailor platform lessons.
CTO
PrepFactory
- Rebuilt the entire application stack: MySQL, PHP (Codeigniter), and React.
- Migrated servers from Azure custom machines to standardized Docker containers.
- Migrated self-hosted MySQL to modern Planetscale with auto scaling and leading security.
Software Engineer
PeerTeach
- Created printing, scanning, and grading systems for classroom assessments.
- Managed a MongoDB-to-PostgreSQL migration and database refactoring.
- Created onboarding tours and implemented product analytics.
Senior Software Engineer
SlashAuth
- Created an npm package for drop-in authorization components.
- Refactored an administrator portal to allow sub-administrators.
- Restyled a dashboard to Figma design standards with Tailwind CSS.
CTO
Quickcard
- Developed a sales document editor with text, image, video, and web embeds.
- Crafted a full analytics stack allowing users to track document interactions.
- Engineered a client link creation process that includes selecting resources, tailoring criteria, injecting variables, and providing alternative recommendations.
Full-stack Engineer
Studio Corsair
- Created a performance metric dashboard aggregating data from Google Ads, Google Analytics, Facebook Ads, and Shopify APIs.
- Engineered a cost-per-acquisition table breaking down costs by customer location.
- Built a Bash shell script to streamline the creation of version release notes.
Front-end Engineer
PrepFactory
- Created a calendar application with a drag and drop interface.
- Engineered a scientific calculator and question-overlay whiteboard.
- Developed a teacher onboarding flow with animations.
Software Engineer
LINKA Technologies
- Created a customer onboarding automation system with Shopify, Mailchimp, Typeform.io, HelloSign, HubSpot, Stripe, and Zendesk webhooks and APIs.
- Integrated Authorize.net's payment support into back-end payment infrastructure.
- Migrated payment systems to comply with Stripe Strong Customer Authentication (SCA).
Project History
Freelance Marketplace
AI and K-12 Education Startup
AI and English Learning Startup
Tutoring Application
https://www.prepfactory.com/Peer Tutoring App
http://www.peerteach.orgSales Deck Web App
Marketing Analytics
Bike Share Software
Education
Bachelor's Degree in Engineering
University of Maryland - College Park, MD, USA
Skills
Libraries/APIs
React, Node.js, REST APIs, Claude API, OpenAI API, Stripe, Google Maps API, OpenCV, Vue, Playwright, Google Maps
Tools
Claude, ChatGPT, Whisper, Claude Code, Codex, Slack, WebStorm, Figma, Amazon Cognito, Shadcn UI, Prisma, LearnDash, Shadcn
Languages
TypeScript, JavaScript, CSS, HTML, Python, SQL, PHP, Java, HTML5
Frameworks
Next.js, Tailwind CSS, Express.js, Ionic, Flask, CodeIgniter, NestJS, Electron, Svelte, React Native
Paradigms
E2E Testing, Testing, Automation, API Architecture, DevOps, Automated Testing, Test Automation, Real-time Systems, Model Context Protocol (MCP), Desktop App Development, Agile, Scrum, HIPAA Compliance, Mobile Development, UX Design, App Development
Platforms
Amazon Web Services (AWS), Vercel, Microsoft, Twilio, MacOS, AWS Lambda, WordPress, Android, Mobile, iOS, Shopify, Linux, Windows, Azure, HubSpot, Google Ads
Storage
PostgreSQL, JSON, Databases, MongoDB, MySQL, Amazon DynamoDB, Redis
Industry Expertise
Cybersecurity
Other
System Design, Full-stack, Full-stack Development, Software QA, Software Architecture, Technical Leadership, Back-end, APIs, Architecture, CTO, Supabase, Artificial Intelligence (AI), Large Language Models (LLMs), Web Development, API Integration, Retrieval-augmented Generation (RAG), Prompt Engineering, Agentic AI, AI Tools, Dashboards, Reliability, Security, JSON REST APIs, Front-end Development, SaaS, Technical Project Management, Quality Assurance (QA), Payment APIs, Authentication, Magic Link, AI-assisted Development, Generative Artificial Intelligence (GenAI), Minimum Viable Product (MVP), Product Management, AI Integration, Third-party APIs, Cloud Platforms, AI Automation, Scalability, Software Design, Code Auditing, Product Engineering, Web Scalability, Prototyping, Global Team Management, Product Strategy, System Integration, Business Requirements, Process Mapping, Solution Design, Workflow Automation, Row-level Security (RLS), AI Chatbots, Conversational AI, User Experience (UX), User Interface (UI), Webhooks, QA Automation, Leadership, Front-end, Software Engineering, MVP Design, Engineering, OpenAI, Startups, Vibe Coding, Proof of Concept (POC), Gemini, Gemini API, Cursor AI, AI-generated Code, Vector Databases, Anthropic, System Architecture, Financial UX, CRM, Customer Relationship Management (CRM), Accessibility, Web Accessibility, CI/CD Pipelines, WebSockets, Monorepos, AI Product Management, Fractional CTO, Legacy Code, Agentic Engineering, Cloud Infrastructure, Data Management, Data Modeling, AI Voice Agents, Scheduling, Message Queues, Queuing Systems, Real-time Data, Consulting, Technical Hiring, UI Design, Product Design, Team Building, Stakeholder Interviews, Agentic RAG Systems, AI Avatars, Avatars, RAG Architecture, Scalable Vector Databases, Entrepreneurship, Data Scraping, Web Scraping, Image Manipulation, Machine Learning, Recommendation Systems, Computer Vision, Monday.com, Identity Verification, Figma to React, Desktop App, Application Packaging, HIPAA, Railway, AI Model Training, LLM APIs, Marketplaces, Mobile Apps, Data Visualization, Integration
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