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Hire the best Java Developers in San Francisco, CA

Check out Java Developers in San Francisco, CA with the skills you need for your next job.
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Clients rate Java developers
Rating is 4.7 out of 5.
4.7/5
based on 398 client reviews
  2. Development & IT Talent
  3. Java Developers
  4. United States
  5. (Current) San Francisco, CA
  • $67 hourly

    • 5.0/5
    • (20 jobs)
    The two-second version: Oracle-trained engineer with 5+ years of software experience, impacting millions of users globally. Built cloud services powering industry giants and praised for top-tier project delivery. Clients say: 'Andrew is an expert of the highest caliber.' Ready to bring Fortune 500 expertise to your next project? Let’s create something extraordinary. -------- The longer, sit-down version: Pleasure to meet you! I'm Andrew. Most clients enjoy working with me because of my cheerful demeanor, prompt communication, and ability to build productive relationships where they feel better off after collaborating with me. I’m passionate about delivering results that exceed expectations while making the experience enjoyable and professional. As a skilled Software Engineer with over 5 years of experience, including a pivotal role at Oracle (Fortune 500), I’ve built scalable solutions that have impacted millions of users globally. I bring a deep understanding of cloud services, web/mobile development, and DevOps, delivering high-impact results. 💡 Key Achievements: •Developed managed cloud services like OpenSearch and Redis at Oracle, powering critical workloads. •Played a key role in building healthcare services (FHIR), delivering in time for audit deadlines, supporting thousands of users. ⭐️ Client Testimonials: • "Andrew is an expert of the highest caliber. He delivered a custom-built webpage that exceeded my expectations." • "Very good communication, delivered on time. It was nice working with him!" 💼 How I Can Elevate Your Project: •Web Development: Expert in JavaScript, React.js, Node.js, Python, and more •Mobile Development: Proficient in Java, Kotlin, Swift, and Flutter •Cloud & DevOps: Extensive experience with AWS, Azure, GCP, and Oracle Cloud •Database Management: Skilled in MySQL, PostgreSQL, MongoDB, and Oracle DB •API Integration: Specialized in RESTful APIs, OpenAI, Stripe, Elasticsearch, and Redis, Rentec, Real Estate Software, Twilio 🌟 Why Choose Me: • Fortune 500 Expertise: Built cloud services used by millions. • Versatile Skill Set: Full-stack development, cloud infrastructure, DevOps, mobile development. •Client-Centric Approach: Focused on clear communication and exceeding client expectations. •Proven Results: Consistently delivered high-quality work on time and within budget. 📩 Let's connect and discuss how I can help turn your ideas into reality. Whether you're a startup looking to launch your first product or an established company seeking to modernize your tech stack, I'm ready to bring my Fortune 500 expertise to your project and create something extraordinary together!
    Featured Skill Java
    Back-End Development
    Full-Stack Development
    Web Application
    Web API
    Database
    iOS Development
    WordPress
    API Integration
    HTML
    Python
    Desktop Application
    Android App Development
    Python Script
    ChatGPT
  • $80 hourly

    • 4.6/5
    • (5 jobs)
    Over 10 years of experience in backend, mobile, desktop, and cross-platform development with a myriad of languages & platforms for major software companies in the bay area and around the world. Strong background in advanced algorithms, data structures & high-performance multithreading. Specialization in advanced build tooling including Bazel, Buck & Pants, and a leading Bazel community expert with proven expertise in porting many millions of lines of code to build & test with Bazel.
    Featured Skill Java
    Buck
    Golang
    Build Automation
    Reactive Programming
    Android SDK
    iOS Development
    Kotlin
    Scala
    Swift
    C++
  • $150 hourly

    • 5.0/5
    • (6 jobs)
    Howdy there! I started off as an AI trainer for OpenAI in 2019 where I worked on a number of tasks involving hallucinations and GPT's ability to interpret natural language. Most recently, I was a prompt engineering consultant for Northbeam, where I investigated the viability of proposed LLM products; most prominently a product that used the GPT API to convert natural language questions about customer data into SQL queries. I've also started CitationAI on the side, a company that with the goal of using LLMs to help researchers extract relevant passages from academic literature based on user input. I am proficient in the following skills: -Out-of-the-box prompt design methods -RLHF -Few-shot prompting -Zero shot prompting -Python -Writing GPT API calls -SQL -BigQuery -Excel and Google Sheets -AI training and writing AI training documentation -Data labeling -Data entry
    Featured Skill Java
    HTML
    Scientific Writing
    SEO Audit
    Molecular Biology
    Social Media Plugin
    Biochemistry
    Digital Marketing
    SQL
    Python
    Prompt Engineering
  • $75 hourly

    • 4.7/5
    • (22 jobs)
    A Senior Software Engineer with a strong background in developing innovative APIs and software applications. My expertise lies in JavaScript, TypeScript, Node.js(NestJS/Express.js/Strapi), React, Next.js, Vercel, React Native, Tailwind CSS, HTML5/CSS3, Material UI, AngularJS/Angular, Ruby on Rails, Python/Django, FastAPI, Hubspot, and Restful APIs, among others. I have a proven track record of successfully integrating digital applications with physical devices, focusing on scalability, security, and interoperability. I've worked closely with cross-functional teams to align API development with user requirements and mission objectives. My innovative approach to connectivity challenges has resulted in improved device communication and user experience. I'm skilled in implementing rigorous testing and optimization to ensure API stability and performance. My experience also includes designing and developing desktop applications, incorporating machine learning techniques, and ensuring data security and privacy. I'm proficient in utilizing AWS, Electron, and GitHub Actions for cloud-based services, native desktop environments, and CI/CD. The projects I contributed have received positive feedback for their innovative approach to accessibility and data security.
    Featured Skill Java
    FastAPI
    Django
    Ruby on Rails
    RESTful API
    Amazon Web Services
    ExpressJS
    NestJS
    Web Development
    Web Application
    Next.js
    Node.js
    TypeScript
    Python
    React
  • $80 hourly

    • 5.0/5
    • (20 jobs)
    I help companies make strategies and visual assets to inform, impress, and influence their stakeholders. I weave together software, UX, and graphic solutions to transform complex data into compelling and memorable statements. With extensive experience in the public, private, and nonprofit sectors, I bring a comprehensive skillset and diverse background to my work, underpinned by a deep understanding of analytical insights. My mission is to assist companies looking to leave a lasting impression in the digital age, and I am proud to have played a role in bringing their environmental and technology-driven concepts to life. Your investment in my design services will come along with consistent support, rapid responsiveness, and documentation made to guide you along in the process. By creating a unique brand and successful marketing campaign through eye-catching design, you will increase your brand recognition and customer engagement. I focus on keeping styles concurrent with industrial standards while setting your business apart from the competition. In turn, long-term benefits can be seen when you have a recognizable and consistent visual identity.
    Featured Skill Java
    UX & UI
    Interactive Data Visualization
    Data Visualization
    Mapbox
    Web Scraping
    GIS
    Blender
    Video Editing
    QGIS
    ArcGIS
    Adobe After Effects
    Adobe Illustrator
    Infographic
    Adobe Photoshop
  • $150 hourly

    • 5.0/5
    • (7 jobs)
    Hi I’m David. I’m a Principal Software Engineer with over a decade of experience working at startups and big tech companies in the Bay Area, most recently TikTok and Salesforce. At TikTok I was a leader on several teams, including user growth focusing on the new user FYP recommendations engine. 🔵 Expert-Vetted top 1% at Upwork 🔵 I'm experienced in building AI, AI RAG, Ad Tech, Mar Tech, CRM, and other business software. 🔵 Core backend developer for multiple Billion+ DAU applications Can help your business with: ⭐️ Developing high-performance backend architectures using the latest cloud technologies. ⭐️ Implementing DevOps strategies for streamlined and secure software deployment. ⭐️ Building scalable CRM and marketing solutions with dynamic integration frameworks. ____________________________________________________________________________________________ As a seasoned Software Engineer focused on AI, backend systems, DevOps, and full-stack development, I am dedicated to empowering startups and established enterprises to exceed their technological objectives. If you're aiming to surpass industry standards and innovate at scale, you've found the right expert! Why work with me? Here are the facts: 🦖 10+ years of hands-on industry experience 📍 Located in the heart of Silicon Valley, San Francisco, CA, USA 🛠️ Mastered technologies including Generative AI, RAG, AWS, Spring Framework, Kafka, Go, and MySQL 🌟 Led key initiatives at TikTok, enhancing user growth onboarding and developing a comprehensive SAAS CRM platform 🚀 Played a pivotal role at Salesforce leading AdTech projects and real-time data processing advancements 📈 Built and managed systems with ultra-high throughput and complex data pipelines 🔗 Facilitated dynamic integrations and machine learning model implementations for lead scoring and actionable insights ___________________________________________________________________________________________ Skillset: 🧠 Generative AI (OpenAI, ChatGPT, API integration, GPT-3.5, GPT-4, TensorFlow, OpenCV, Python, Retrieval Augmented Generation, PyTorch, LangChain, Open-source LLMs Mistral AI, LLaMA2, WizardLM, Falcon LLM) 📊 Backend Engineering Mastery (Java, Spring Boot, Spring Framework, Go) 💡 Expert in Cloud and Big Data (AWS, Apache Hive, Kafka, Redis, DynamoDB) 🔧 DevOps Excellence (Terraform, Amazon EC2, CDN, Puppet, Networking) 🔄 Full-Stack Development Proficiency (Java, Python, TypeScript, Node.js, React) 🗄️ Database Architecture and Design (MySQL, Database Scaling, Performance Optimization) 🤝 Leadership and Team Collaboration (Tech Lead, Cross-Functional Team Management) 🎛️ Backend Framework Expertise (Django, Flask, Play Framework) 🛠️ Infrastructure and Deployment (Kubernetes, Nginx, Amazon RDS, Amazon Lambda) 📈 Real-time and Large-Scale System Design (High QPS API Design, Real-time Segment Processing) 📜 Certifications (AWS Certified Solutions Architect, CCNA) ___________________________________________________________________________________________ If you're looking for a proven technology leader who can navigate the complexities of your backend systems and scale your infrastructure to meet tomorrow's demands, let's connect and explore how we can achieve your vision together.
    Featured Skill Java
    MySQL
    Salesforce CRM
    Django
    CRM Development
    Network Engineering
    Google Cloud Platform
    Apache Kafka
    Spring Framework
    Data Ingestion
    Amazon Web Services
    CRM Software
    Marketing API Integration
    Golang
    Advertising Platform
  • $100 hourly

    • 5.0/5
    • (3 jobs)
    Hey! I'm originally from San Francisco, CA. I spent 7 years at Twilio, most recently serving as the Technical Lead for the IoT Usage and Billing team based out of Berlin. I have created - and improved - dozens of systems during my time at Twilio. I have experience working on backend high-scale distributed systems, leading projects from the design phase all the way to release and long term support. On the frontend I've also shipped changes to Twilio's React based console. I've spent my entire career working in teams to accomplish more than we could individually. Specific Skills - Managed servers running in AWS - Expert in Java/Scala (especially ZIO/cats, akka), Python (gevent, flask, fastapi, SQLAlchemy) - Expert in REST API design - Experience using various datastores, MySQL/Postgres, Dynamo DB, Cassandra, (+ data and schema migrations on these systems) - Experience writing data scraping scripts - Experience in NodeJS - Passionate about frontend design - Have built websites from the ground up in Typescript, React JS, Recoil, Tailwind, NextJs. - Led a team of engineers for 2 years, where I pushed for high coding standards and maintainability, and reduced team technical debt by 50% - Build out the Super SIM product at twilio from MVP all the way to 1M+ SIMs - 7 years experience in shipping changes to production code with no downtime. In my free time I enjoy working on personal programming projects, reading blogs, playing basketball, going skiing, and traveling. I recently just wrapped up a trip through Thailand and Vietnam :). I'm looking to do freelance work to have more flexibility in the work I take and the hours I work.
    Featured Skill Java
    Apache Kafka
    Asynchronous I/O
    BigQuery
    CI/CD
    HAProxy
    Functional Programming
    API Development
    Docker
    Scala
    Amazon DynamoDB
    Git
    Amazon Web Services
    MySQL
    Python
  • $50 hourly

    • 5.0/5
    • (1 job)
    - Master's Computer Science from Northeastern University - 3 years' experience in developing full-stack applications. - Coding Languages: Python, JavaScript, Java, C - Other Language/tool: HTML, CSS, R, TailwindCSS, Bootstraps, Jira, Docker - Framework: Flask, React, Node, Express, AWS DynamoDB, MongoDB, MySQL, AWS Chalice - Native fluency in English and Chinese - 1 year Start-up experience: - Set up CI/CD pipelines with AWS Code Pipeline - Developed serverless applications with AWS Lambda and API Gateway using the AWS Chalice framework, - Configured domain servers with AWS Route 53.
    Featured Skill Java
    User Interface Design
    API Development
    REST API
    Figma
    Jira
    AWS Lambda
    Flask
    Git
    CSS
    HTML
    TypeScript
    JavaScript
    React
    Python
  • $45 hourly

    • 5.0/5
    • (5 jobs)
    Hi there! I’m a Senior Software Engineer with over 10 years of experience in the software development industry. I specialize in designing, developing, and deploying software applications and features. I have a strong background in the software development life cycle (SDLC) and am proficient in writing clean, concise, and efficient code. I have experience managing code documentation and version control, and I’m comfortable working in an agile environment to release software on a regular schedule. I’m passionate about staying up-to-date with the latest technologies and enjoy collaborating with internal teams to architect, build, and test new features. I’m confident that my skills and experience make me a great fit for your project.
    Featured Skill Java
    Flutter
    Swift
    React
    Android
    iOS Development
    Architectural Design
    Agile Software Development
    App Development
    Cloud Computing
    Node.js
    React Native
  • $50 hourly

    • 5.0/5
    • (1 job)
    I'm a backend developer with 5+ years of industry experience who is interested in building scalable and efficient backend systems. I am most knowledgeable in scaling large databases, building complex APIs, and streamlining data pipelines. I also have a strong sense of ownership and leadership and will fully close out any task with no loose ends.
    Featured Skill Java
    Data Engineering
    Back-End Development
    SQL
    Kotlin
    Python
    GraphQL
  • $45 hourly

    • 4.6/5
    • (6 jobs)
    Hi, I’m Teiana and I'm new to Upwork (as of April 2024!) and I'm a highly motivated data scientist, who has worked as a bioinformatician, has 4+ years of life sciences research experience with a great track record of building data platforms and innovative solutions to drive actionable insights for business cases. I'm experienced in automating data workflows, building analyses, high-throughput pipelines for various inquiries, consulting with colleagues to optimize business products, and writing technical reports and publications. I am interested in any general programming, bioinformatics, business analyst, or technical writing opportunities you may have! - Computational skills: Nextflow, Python, R, C++, Java, bash, Tableau, Power BI, Unix/Linux, SQL, Git, and experience with AWS infrastructure (including EC2, S3, and batch).
    Featured Skill Java
    pandas
    Clinical Trial Management System
    Microbiology
    Sequence Analysis
    Genomic Data Analysis
    Tech & IT
    Bioinformatics
    Technical Project Management
    Technical Writing
    Digital Publication
    R Shiny
    RStudio
    AWS Cloud9
    Python
  • $50 hourly

    • 5.0/5
    • (1 job)
    I'm a QA engineer with over 12 years of industry experience in software quality and testing. I acquired a wide array of skills and insights from leading and supporting QA in multi-team projects. Whether you need targeted feature testing or an in-depth test execution plan before release, I can help. -Test planning and execution for Web, API, and mobile devices -Create or update automation framework or CI/CD infrastructure -Create Jira dashboards and TestRail projects -Can help manage testing from start to finish (SIT, UAT, Regression, Release)
    Featured Skill Java
    API Testing
    Test Execution
    CI/CD
    Jenkins
    Selenium
    TestNG
    TestRail
    Jira
    Test Management
    Test Plan
    Mobile QA
    QA Management
    QA Software & Testing Tools
    Test Automation
  • $65 hourly

    • 5.0/5
    • (24 jobs)
    I have worked in software development for 15 years both as coder implementing backend (Java) and front technologies (HTML, CSS) as well as a software architect. I have been responsible for end user documentation for APIs as well requirements and design specifications. I've worked with various project stakeholders and clients to develop requirements and projects plans. I have worked with UX engineers to help refine designs and created mocks ups of wireframes, UML diagrams and other visual assets. When not working, I am a singer/songwriter. I have released multiple albums and perform regularly in the Bay Area. I maintain my own music publishing company and my own website as an artist. I have been writing creatively from a young age -- I was illustrating my own short stories as early as kindergarten and wrote the play for the student production my senior year of high school. I also paint with acrylics.
    Featured Skill Java
    Technical Editing
    Requirements Specification
    API Documentation
    Sequence Diagram
    SEO Writing
    Technical Writing
    XML
    Swagger
    Unified Modeling Language
    SQL
    CSS
    JavaScript
    HTML
  • $75 hourly

    • 0.0/5
    • (1 job)
    I am a Software Developer and Data Engineer with work experience in Python. I have experience with APIs, web scrapers, and data pipelines!
    Featured Skill Java
    pandas
    SQL
    ETL
    GitHub
    Bash Programming
    NumPy
    Bash
    Python
    Selenium
    Beautiful Soup
  • $62 hourly

    • 0.0/5
    • (0 jobs)
    Software engineer with more than 10 years of experience and a deep passion for clean and efficient code. I am very proficient working on the backend but also can work on the front-end if needed.
    Featured Skill Java
    Cloud Computing
    Angular
    Cloud Application
    TypeScript
    SQL
    Python
  • $70 hourly

    • 5.0/5
    • (1 job)
    Authorized to work in the US. I'm a software development engineer with 9 years' practical experience in the development of various business applications. I have knowledge of the full-stack technologies in the frontend, backend and Mobile(IOS,Android) development (for the last 5 years). I keep in mind end-user needs, develop solutions with a user-friendly and intuitive interface.
    Featured Skill Java
    SQL
    Jira
    Git
    iOS
    Swift
    Kotlin
  • $110 hourly

    • 0.0/5
    • (0 jobs)
    My company is focused on developing software for autonomous UAV/UGV and also providing NLP solutions to customers. My career has been a journey through diverse roles – from engineer in a major corporation like Oracle Inc to an entrepreneurial. This varied experience has shaped my approach to technology: endlessly curious, deeply focused on business outcomes, and consistently centered around people. My passion lies in harnessing technology not just for innovation but for its potential to empower individuals and communities. Here are the key attributes that define my approach: Technically Curious and Versatile: Constantly learning and adapting to new technologies across industries and roles. Business Acumen and Mission-Driven: Merging deep business insight with a clear understanding of mission to deliver impactful technology solutions. People-Centric Technology Solutions: Advocating for solutions that amplify human potential, with a focus on putting people at the forefront of technological progress. Broad Leadership Experience: Leading with empathy, energy, and dedication in both startup environments and major global corporations. Mentorship and Collaboration: Guiding younger professionals, aiming to create a future where technology and humanity harmonize. Strong Interpersonal and Communication Skills: Building enduring relationships and communicating effectively across all levels of organizations. At this pivotal stage of my career, my commitment is to drive significant change – by mentoring emerging technologists, contributing to impactful projects, and ensuring that our advancements in AI and technology enrich and elevate our human experiences. I also completed graduate certification from Stanford on: SCPD Mining Massive Data Sets Graduate Certificate (completed) - SCPD AI Graduate Certification (complete) -
    Featured Skill Java
    Cloud Application
    GPU
    PyTorch
    Python
    Image Classification
    NLP Tokenization
    Oracle Programming
    Oracle Enterprise Service Bus
  • $90 hourly

    • 0.0/5
    • (0 jobs)
    Overview Summary As an internet pioneer and seasoned software product developer, I’ve dedicated over 30 years to creating groundbreaking technologies that have redefined digital communication and infrastructure. From developing early client-server tools to leading innovations in mobile and scalable cloud solutions, I've contributed to significant advancements that continue to shape the tech landscape today. Key Career Highlights: Client-Server Tools (1990): Created the first tools for developing Windows-based applications with Macintosh interfaces, powered by robust UNIX and supercomputer backends, including use cases for institutions like CERN in Geneva. These tools laid the foundation for distributed computing and efficient cross-platform integration. Comsurfer Email Client (1992): Developed Comsurfer, the first GUI email client for Windows, seamlessly integrating Internet email into LAN systems and introducing reliable email notifications. This innovation provided a cost-effective alternative to fax communication and streamlined business operations. Corporate Email Server (1994): Co-developed the first Internet email server for corporate use, enabling organizations to exchange emails globally. Clients included major pizza chains in the US and multinational companies like L’Oreal, marking a significant leap in corporate communication infrastructure. Mobile Email Technology (1996-2000): Created the first mobile email solutions, enabling on-the-go access to Internet email. Launched first by Zaz in Brazil, the technology evolved and was adopted by Vodafone in 1999, featuring visual interfaces for Vodafone Live’s high-resolution color screens in 2000. These innovations revolutionized mobile communication and paved the way for future mobile messaging technologies. Freedom Pix (2010): Developed Freedom Pix, the first iOS chat app to bypass mobile carriers using regular phone numbers, redefining mobile communication and challenging traditional carrier models. ChatMail (2011): Co-developed ChatMail, the first app to leverage the email protocol for chat-like messaging, transforming email into a real-time communication tool and providing seamless, asynchronous connectivity. Setip.io (2023): Created and launched Setip.io, a cutting-edge deployment platform for startups, enabling independence from cloud vendors while ensuring hyper-scalability and robust security. Setip.io optimizes resources and provides resilience to security threats, catering to the evolving needs of fast-scaling businesses. Technical Skills Client-Server Architecture: Expertise in developing cross-platform integration tools for efficient and scalable computing environments. Email Systems Design: Extensive experience in building GUI-based email clients, server infrastructure, and pioneering push notification technology. Mobile App Development: Proficient in creating mobile communication solutions, from early mobile email systems to modern OTT apps that bypass carriers. Distributed Systems & Scalability: Developed solutions for secure and efficient resource management, including horizontal and vertical scaling of applications. Over-the-Top (OTT) Communication: Innovated chat and messaging platforms that challenge traditional carrier services, enhancing user experience and connectivity. Secure Deployment Solutions: Designed Setip.io to provide startups with scalable, secure, and vendor-independent deployment capabilities. Professional Experience Client-Server Development Tools (1990) Created and developed tools that enabled seamless Windows-Macintosh application integration with UNIX and supercomputer backends, adopted by CERN for high-performance computing needs. This work laid the groundwork for future distributed systems and enterprise-level software solutions. Comsurfer & Corporate Email Server (1992-1994) Created and developed Comsurfer, the first GUI email client for Windows, integrating Internet email into internal LAN communications. Introduced reliable email notifications, transforming email communication efficiency. Co-developed the first corporate Internet email server in 1994, facilitating global email exchanges. Implemented in diverse sectors, from US pizza chains to L’Oreal, enhancing global business communications. Mobile Email Technology (1996-2000) Created and developed the first mobile email solution, initially deployed by Zaz in Brazil and later adopted by Vodafone. Developed for Vodafone Live, this technology introduced high-resolution visual interfaces, setting the standard for modern mobile email services and transforming global mobile communication. Freedom Pix & ChatMail (2010-2011) Created and developed Freedom Pix in 2010, revolutionizing iOS communication by bypassing mobile carriers. This app leveraged regular phone numbers, offering flexibility and reducing user costs. Created and co-developed ChatMail in 2011, an innovative chat application that used the email protocol to enable real-time chat experiences. This approa
    Featured Skill Java
    AWS Development
    IT Capacity Planning
    Infrastructure as Code
    DNSsec
    DNS
    Swift
    Docker Swarm Mode
    SaaS Development
    SaaS
    Microservice
    React
    MongoDB
    Docker
    Kubernetes
  • $150 hourly

    • 0.0/5
    • (0 jobs)
    Navigator and catalyst for team and partner success. It could be mentoring, optimizing, crisis management, or adding the right ingredients/expertise from my depth of knowledge to drive the results to deliver. My reputation is one of an innovator, results generator as a highly resourceful hands-on software engineering leader. My specialties being in large scale transactional systems integration and big data. My business domain knowledge spans the investing/banking, real estate and medical IT spaces.
    Featured Skill Java
    AWS Development
    Linux
    Artificial Intelligence
    Leadership Skills
    Engineering & Architecture
    Python
    Python Script
    Data Engineering
  • $100 hourly

    • 0.0/5
    • (0 jobs)
    OBJECTIVE Back-end Staff software engineer in San Francisco area, California QUALIFICATIONS * U.S. Citizen * Master of Computer Science, Arizona State University * Over 10 years of full-stack J2EE enterprise development experience * 4 years of experience in cloud environment (AWS, GCP) * 4 years FinTech work experience (Visa, Wells Fargo)
    Featured Skill Java
    MySQL
    Oracle
    Microsoft SQL Server
    Apache Tomcat
    GitHub
    Amazon Web Services
    JSON
    Jenkins
    Apache Maven
    REST API
    Spring Framework
    Spring Boot
  • $22 hourly

    • 5.0/5
    • (2 jobs)
    I am a developer experienced with creating automations for businesses, working with API's, and working with databases.
    Featured Skill Java
    API Integration
    n8n
    CircleCI
    Zapier
    AI Builder
    LLM Prompt Engineering
    SQL
    Python
    Automation
    Mobile App
    Artificial Intelligence
    iOS Development
  • $40 hourly

    • 0.0/5
    • (0 jobs)
    Proficient in Excel, R, and data science tools, I specialize in advanced functions, data visualization, statistical modeling, and process automation. With a Bachelor of Science in Cognitive Science and a Data Science Certificate from Yale, I have a strong foundation in analytical problem-solving and technical expertise. Previously, I was part of a nine-member investment team at Partners Capital in San Francisco, where I applied my data analysis and communication skills to drive strategic decision-making. My experience includes creating intricate financial models, extracting insights from large datasets, and delivering clear, actionable recommendations. As the founder of Ace Bridge, I honed my entrepreneurial skills and developed a results-oriented approach to tackling multifaceted challenges collaboratively. This background allows me to combine creativity with technical precision to meet diverse client needs. If you’re looking for a detail-oriented professional who can bring clarity and precision to your data-driven projects, let’s collaborate! Regular communication is important to me, so let’s keep in touch. I'm known for my accountability + sense of ownership.
    Featured Skill Java
    Alpha Testing
    Beta Testing
    Analytical Presentation
    Data Mining
    ChatGPT
    Artificial Intelligence
    Python
    Analytics Dashboard
    Analytics
    Excel Macros
    Excel Formula
    Microsoft Excel
    R
    Data Analysis
  • $95 hourly

    • 0.0/5
    • (0 jobs)
    I’m a seasoned software engineer with a proven track record in AI, SaaS, and financial modeling platforms, specializing in C#/.NET, Golang, React, AWS, PostgreSQL, and LLMs. With 18+ years in Java and enterprise software, I’ve built scalable backend systems, high-performance APIs, and intuitive frontend experiences. I played a pivotal role in building a flagship financial modeling SaaS platform from scratch, helping secure $25M in Series B funding. My expertise spans architecting scalable APIs, designing custom scripting languages for financial models, and optimizing performance at scale. I thrive at the intersection of engineering, product, and UX, translating business needs into efficient, user-friendly solutions. Whether it’s building AI-powered applications, optimizing SaaS platforms, or crafting robust backend systems, I deliver high-quality, scalable code that drives business success. Let’s build something great together. Get in touch!
    Featured Skill Java
    Microservice
    REST API
    Docker
    Amazon Web Services
    GraphQL
    React
    Golang
    Python
    PostgreSQL
    LLM Prompt Engineering
    SuiteScript
    SQL
    .NET Core
    C#
  • $80 hourly

    • 0.0/5
    • (0 jobs)
    I am a software engineer and entrepreneur. I have started two companies in my life which has shaped me in more ways that I can imagine. I enjoy using new technology and learning about new patterns. I mostly specialize in web technologies but also focus on ML, big data and real-time architecture. You can find some of my projects on Github. I was born in Iran and moved to Seattle at a young age. I started programming in high school and studied computer science at the George Washington University in Washington DC. After graduating, I worked at AOL on aol.com which taught me a lot about scalability. I left to join Opower in Arlington, VA. Opower started my career in management. I left to start my own in Los Angeles and eventually moved to San Francisco where I joined Opower for their IPO in 2014. I led teams at Quid, Capital One labs in SF and data and infrastructure at UJET. I currently live in the South Bay and work at Google building their internal CRM. I am a husband and father of one.
    Featured Skill Java
    PHP
    MySQL
    MongoDB
    ExpressJS
    Node.js
    React
    JavaScript
    Ruby on Rails
  • $83 hourly

    • 0.0/5
    • (0 jobs)
    I am a cybersecurity consultant and penetration tester with expertise in web application security, network security, and vulnerability assessments. With experience at Aon and Stroz Friedberg, I have conducted in-depth security assessments to help clients identify and remediate vulnerabilities. My background in mathematics (B.A. from Princeton, M.A. from UCSB) helps me think logically and break down complex problems. I am proficient in Burp Suite, LaTeX, Python, Java, C++, SQL, Wireshark, and various security tools.
    Featured Skill Java
    Computing & Networking
    Mathematics
    LaTeX
    Computer Science
    Red Team Assessment
    Ethical Hacking
    Network Penetration Testing
    Web App Penetration Testing
    Penetration Testing
    Information Security
    Graph
    Database Management
    Network Engineering
    Computer Network
  • $60 hourly

    • 5.0/5
    • (2 jobs)
    I have ten years' programming experience. I am proficient in Java, C, C++, C#, Visual Basic, VBA, Python, PHP, SQL, Access, SAS, R Programming, HTML, CSS, JavaScript, JQuery, NodeJS, AngularJS, Bootstrap, Excel, PowerPoint, Dreamweaver, Photoshop, Illustrator, InDesign, Squarespace, and WordPress. I offer training in the subjects listed above. I also offer web development, software development, and mobile application development services to clients.
    Featured Skill Java
    Software Development
    Node.js
    Android App Development
    iOS Development
    CSS
    C#
    JavaScript
    HTML5
    WordPress
    SQL
    Python
    PHP
  • $225 hourly

    • 5.0/5
    • (11 jobs)
    I am a freelance software engineer specializing in mobile app and full-stack software development. I have over 20 years of experience in professional software engineering. The last seven years of that has been working on web and mobile apps, their backends, cloud infrastructure, and devops. I am available for short-term freelance software engineering contracts in web full-stack, mobile app, and cloud infrastructure development, using Swift, Kotlin, React, TypeScript, JavaScript, Python, Java, Erlang, OCaml, Objective-C, and C. I work on multiple platforms including Docker, Amazon Web Services, Google Cloud, Linux and macOS. I have used many database backends, including ElasticSearch, MySQL, and PostgreSQL. I strongly prefer remote contracts, though I am open to work in the San Francisco area. Before freelancing I was the chief architect and founder at Tipbit, an email, calendar, and contacts app for iPhone and iPad. I have previously held roles as architect and director for XenServer at XenSource and Citrix, and founding engineer and technical board member for OpenStack. In general I have been a software engineer in telco, virtualization and cloud since 1997. I am a UK and US dual citizen. I have a degree in Computer Science from the University of Cambridge.
    Featured Skill Java
    Erlang
    Xen Project Hypervisor
    OCaml
    iOS Development
    Kotlin
    Android
    Python
    Swift
    Amazon Web Services
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