Serhii Lozovskyi
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DEVELOPMENT · AI & AUTOMATION · AI-ASSISTED

SerhiiLozovskyi

Developer · AI & Automation · AI-Assisted Development · Prompt Engineering

I build products end-to-end — fast on no-code/low-code (Bubble, Webflow), hardened with real code (custom APIs, plugins, integrations) — and automate the rest with n8n, Make and LLM agents. AI-assisted development and prompt engineering throughout. 70+ projects shipped, 24+ workflows.

Serhii Lozovskyi
6+
Years experience
70+
Projects
200+
Projects estimated
50+
People mentored
30
Team members mentored
About

Who I am

Hi there! I’m Serhii Lozovskyi. Currently, my professional journey goes. With a unique background spanning roles as a CTO, Bubble Developer, Estimate Manager, and Product Manager, I bring a 360-degree perspective to every project - leading them effectively from the initial spark to a successful launch.

On the technical side, I have a deep-rooted expertise as a Bubble Developer. I build and maintain sophisticated web and mobile applications. Because I have a background in traditional coding—including HTML, CSS, JS, and NodeJS—I don’t just "assemble" apps. I know how to correctly configure data access parameters (Privacy Rules), build secure architectures, and integrate virtually any third-party service.

Beyond traditional and no-code development, I leverage AI-powered tools to dramatically accelerate delivery. Using Claude Code and other AI coding solutions, I rapidly build prototypes and working MVPs—turning concepts into validated products in a fraction of the usual time. I combine these AI-assisted workflows with my engineering background to ensure the output isn't just fast, but also clean, secure, and production-ready.

Throughout my career, I’ve mastered an extensive tech stack. This includes: No-code/Low-code platforms like Bubble, Webflow and others; Databases and Cloud solutions such as AWS, SQL, Notion and Airtable; Automation tools like Make, Zapier, and n8n. Development with Claude Code and other AI solutions.

I also have significant experience in AI implementations (specifically OpenAI), building Web3 and Blockchain solutions (like Hedera and Metamask), and setting up complex API integrations—ranging from payment gateways like Stripe to deep Telegram and Discord integrations... and many others.

My core strength is the bridge I build between deep technical expertise and business-driven thinking. I’d love to discuss how my experience can help bring your next big idea to life.

Capabilities

Development & automation stack

No-code / Low-code

  • Bubble
  • Bubble API & Plugins
  • Webflow
  • FlutterFlow
  • WordPress
  • OpenCart

AI & Automation

  • Claude Code / AI-assisted dev
  • OpenAI / LLM integration
  • AI image / video generation
  • Make
  • n8n
  • Zapier
  • Keragon
  • Model Context Protocol (MCP)
  • Vector databases (Qdrant, Pinecone, pgvector)
  • RAG frameworks (LangChain, LlamaIndex)
  • Embeddings & semantic search
  • Local LLMs (Ollama, LM Studio)
  • OCR / document parsing

Engineering & Code

  • REST API integration
  • HTML / CSS / JS
  • Python
  • Node.js
  • SQL
  • TypeScript
  • Web scraping & data extraction

Cloud, Data & Integrations

  • Stripe
  • SendGrid / Postmark
  • AWS
  • Algolia
  • Airtable / Notion
  • Telegram / Discord
  • Slack / WhatsApp / Gmail
  • Shopify
  • PDF generation (PDFMonkey)
  • Video calling (Daily.co)
Selected work

Built and shipped

11 case studies from 70+ delivered projects.

Winery Management System

SaaS·Team Lead · Full Stack Developer·5 months

Winery Management System (WMS) is a platform for optimizing wine storage and sales processes, helping its users track wine inventory, create wine lists, and manage sales transactions.

Responsibilities
  • participated in all meetings
  • Bubble development
  • Creating a personal Bubble API
  • JS integration
  • Development of an analytics and reporting system
  • Development of a dynamic wine menu where, depending on 3 levels of filtration and 2 levels of sorting, the appearance and the ability to export PDF changes
  • Development of a system of locations in the middle of which different batches of different wines can be located
  • Development of an admin panel for regulating all the possibilities of the site, confirmation and modification of orders, changing the content of sites
  • Development of automatic generation of orders based on images using AI
  • Development of adaptive layout of the entire application
  • Privacy Rules are configured in detail
  • There are also many other functions that I have highlighted the most interesting and complex functions.
BubbleBubble APIAlgoliaApexChartsPDF MonkeyHTML / CSS / JSAPIREST API

Aroma Library

Healthcare / EdTech·Full Stack Developer · Tech Lead·V1 - 8 month V2 - 1 month, until now V3 - Not start

Your Ultimate Learning Platform for Aromatherapy, for beginners and experts alike

Quickly find the right essential oils, formulations, and evidence-based insights to create personalized solutions for your clients - saving you time while ensuring safe, effective results.

Whether you’re new to aromatherapy or an experienced practitioner, project offers reliable information, research-based guidance, and a space to connect with like-minded enthusiasts worldwide.

How is project different from other aromatherapy resources?

Our platform is founded by clinical aromatherapists with 30+ years of experience. We focus on science-backed insights, ensuring safe and effective essential oil use for both personal and professional needs.

Responsibilities
  • participated in all meetings
  • Bubble development
  • Creating a personal Bubble API
  • JS integration
  • Move BD from Xano
  • Creating with bubble Complex Filters (Comparison: thing with thing, list with thing, thing with list, list with list, thing of number with list of ranges of numbers, thing of number with range of number)
  • Development of adaptive layout of the entire application
  • Connection Google analytics
  • Forming links by passes relative to the user's route through the pages
  • Localization of the entire site into two languages with the ability to add more languages
  • Upload oil analysis from xlxs file, where two fields are compound name and percentage of oil content. If such a compound already exists, a new one is not created
  • Develop a unit system that allows switching between different measurement systems and leaving the correct numbers in the selected measurement system relative to the one in which the recipe was created
  • A payment system has been developed that allows you to save all invested funds when changing your subscription up or down, when switching from annual to monthly and vice versa. Two types of payment by invoice through Zapier and by card through Stripe
  • Privacy Rules are configured in detail
  • Each subscription has its own permissions that can be configured from the bubble side. If a subscription does not have a permission but the user tries to get it, he is offered to upgrade the plan.
  • There are also many other functions that I have highlighted the most interesting and complex functions.
BubbleBubble APIAlgoliaStripeZapierDeepLPostmarkGoogle AnalyticsHTML / CSS / JSAPIREST API

Big Idea Platform ↗

Blockchain·Team Lead · Tech Lead · Full Stack·Close to 12 months
  • A platform for creating ideas and patenting them using the blockchain. Additional communication with AWS and document reference database
  • participated in all meetings
  • Bubble development
  • Creating a personal Bubble API
  • JS integration
  • Developed a duplicate entry in AWS and hashing in the Header of ideas to preserve their uniqueness and safety
  • Privacy Rules are configured in detail
  • Letters with dynamics and design were developed using Send Grid
  • The possibility of selling ideas has been developed P2P, P2B, B2B,B2P
  • Developed signing NDA inside the application for idea if there was such a setting
  • Developed dynamic permissions for subscriptions that can be edited on the admin panel
  • Internal analytics has been developed for both users, business accounts and admins.
  • Each document (NDA, Idea, Purchase and Sale Agreement) is duplicated in AWS and hashed in the header, all information can be viewed
  • An activity log system has been developed that allows you to view full information about what happened to some entities (for example: Viewing an idea by another user, any change to this entity, an agreement or file that was signed or associated with the entity, etc.)
  • A system of collaborators with customizable permissions and roles for a specific owner of this entity has been developed
  • Development of adaptive layout of the entire application
  • A system for transferring some entities such as ideas of workshops, etc. has been developed.
  • Each subscription has its own permissions that can be configured from the bubble side. If a subscription does not have a permission but the user tries to get it, he is offered to upgrade the plan.
  • There are also many other functions that I have highlighted the most interesting and complex functions.
  • Responsibilities
    • Quality control, deadlines, development, create technical specifications and communicate with the client
    BubbleAWSHederaMetaMaskVenlyQLDBStripeSendGridHashingHTML / CSS / JSAPIREST API

    Swiftle

    Team Collaboration·Team Lead · Tech Lead · PM · Full Stack·3 month, new version 5 month
  • A platform for communication with clients, signing acts, contracts, creating news for landing, setting roles for workers and clients, payment system,blog builder, admin panel etc.
  • Responsibilities
    • Quality control, deadlines, development of complex parts, create technical specifications and communicate with the client
    • participated in all meetings
    • Bubble development
    • Creating a personal Bubble API
    • JS integration
    • Privacy Rules are configured in detail
    • Development of adaptive layout of the entire application
    • A system for signing certificates of completed work with dynamic fields set by the project manager has been developed. The client has the opportunity to leave feedback on each department that worked on his project, separately
    • Possibility of group correspondence between the client team and the development team, with important messages marked, report template and floup
    • An admin panel has been developed with its own analytics and the ability to create and configure roles and their permissions
    • Payment for development from a platform with stripe integration has been developed
    • Letters with dynamics and design were developed using Send Grid
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleStripeSendGridMakeSQLREST APIHTML / CSS / JSAPIREST API

    Entice ↗

    Social Network·Team Lead · Tech Lead · PM·Close to 6 months

    A Community For Artists To Share Work, Find Jobs, And Be Inspired all on a single platform.

    ENTICE is a creative empowerment community focused on connecting artists and creative people to economic opportunities. We are doing this by building a platform to find inspiration, build your portfolio of work, find your own job opportunities, and sell your own products all in a single space.

    I was the technical lead for this project and sometimes replaced the project manager.

    Responsibilities
    • Quality control, deadlines, development of complex parts
    • participated in all meetings
    • Bubble development
    • Creating a personal Bubble API
    • JS integration
    • Privacy Rules are configured in detail
    • Development of adaptive layout of the entire application
    • Letters with dynamics and design were developed using Send Grid
    • The functions of liking, saving, sharing a post have been developed. Chatting within the community
    • Marketplace platform developed
    • Converted to webApp using BDK and released to AppleStore and PlayMarket
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleBDKStripeSendGridPDF MonkeyHTML / CSS / JSAPIREST API

    Femme Nativa ↗

    Healthcare / Fitness·Tech Lead · Team Lead·Close to 6 months

    Femma Nativa is a fitness app designed for women by women. Our mission is to help women feel great inside and look great outside. Our style of workouts is mostly low impact and includes cardio. All our workouts and programs are designed to get you lean and toned. And when most women start doing this type of workout, their body just transforms. They slim down, they become toned, and they start feeling more confident than ever. Inside the app you will find these:

    1. At-Home Cardio Videos.

    We've got you covered! There are a lot of quick workouts for you to choose from in our Challenges section, and we are continually adding new workouts to keep things fresh and exciting. Getting educated about fitness, nutrition, and health is incredibly important. Getting this type of knowledge will help you get results faster and teach you how to stay on track.2. Goal Tracking. Now you can track your progress all in one place. Upload your progress photos so you can see how far you’ve come on your fitness journey.

    Need a little extra support and motivation (don’t we all?!). You’ve come to the right place! Our community of women is friendly, and supportive and is on a similar journey to you. Create your accountability groups, send direct messages, or read through everyone else’s posts and questions for motivation. And finally, we all know how important nutrition is for not only weight loss but your general health. So we have an 8-week nutrition plan that is tailored to your specific body type. It includes both a regular and vegan meal plan, with over 100 healthy recipes. And this nutrition plan is key to helping you achieve results long term. We have designed the Femme Nativa App to help users achieve long-term success

    Responsibilities
    • Quality control, deadlines, development of complex parts
    • participated in all meetings
    • Bubble development
    • Creating a personal Bubble API
    • JS integration
    • Privacy Rules are configured in detail
    • Development of adaptive layout of the entire application
    • Letters with dynamics and design were developed using Send Grid
    • Converted to webApp using BDK and released to AppleStore and PlayMarket
    • Edit the course, plan, nutrition, link or delete different products in shopify
    • Choice of duration a specific training program.
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleBDKStripeSendGridShopifyHTML / CSS / JSAPIREST API

    Squares ↗

    Marketplace·Full Stack Developer · PM·3 months
  • Marketplace for renting space for events with various loyalty systems integrations
  • Responsibilities
    • Quality control, deadlines, development of complex parts
    • participated in all meetings
    • Bubble development
    • Creating a personal Bubble API
    • JS integration
    • Privacy Rules are configured in detail
    • Development of adaptive layout of the entire application
    • Letters with dynamics and design were developed using Send Grid
    • Hourly booking of different types of locations
    • Location placement by the landlord
    • Automatic calculation of cost depending on addition services
    • Referral system
    • Promocodes
    • Automatic recommendations
    • GPS navigation
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleFigmaHTML / CSS / JSAPIREST API

    Sets Learning ↗

    Education·Tech Lead · Team Lead · Full Stack·4 months

    Platform for learning with the roles of Teacher, Student and Administrator. There is a calendar of classes, video calls, payment via stripe. Opportunity to earn money using the referral program

    Responsibilities
    • Quality control, deadlines, development of complex parts, Assistance in developing technical specifications
    • participated in all meetings
    • Bubble development
    • JS integration
    • Privacy Rules are configured in detail
    • Development of adaptive layout of the entire application
    • Letters with dynamics and design were developed using Send Grid
    • The ability to create your own lessons for students has been developed
    • The ability to set up a calendar for a teacher and book calls with it for a student has been developed
    • Video Calls with Lessonsscape
    • Possibility to pay for calls or a pack of calls using stripe within the platform
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleREST APIStripeDaily.coLessonspaceNativlyHTML / CSS / JSAPIREST API

    Personaliser.io

    Automation / AI·Tech Lead·2 months

    Generate and send personalized messages based on data from LinkedIn using AI

    Responsibilities
    • Quality control, deadlines, development
    • participated in all meetings
    • Bubble development
    • JS integration
    • Development of adaptive layout of the entire application
    • Generate and send personalized messages based on data from LinkedIn using AI
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleOpenAILinkedIn APIHTML / CSS / JSAPIREST API

    Le Collaborateur

    AI·Tech Lead·2 months
  • A platform that allows you to upload documents and edit them using AI, create new versions
  • Responsibilities
    • Quality control, deadlines, development of complex parts
    • participated in all meetings
    • Bubble development
    • JS integration
    • Development of adaptive layout of the entire application
    • A platform that allows you to upload documents and edit them using AI, create new versions
    • There are also many other functions that I have highlighted the most interesting and complex functions.
    BubbleOpenAICustom Bubble pluginHTML / CSS / JSAPIREST API

    Recruitment Platform

    HR / Psychometrics·Full Stack Developer · Tech Lead·4 month

    We enable our clients to generate massive ROI by using scientifically validated psychometric tests to select the best candidates.

    We charge you a simple and transparent flat fee per vacancy. That way, you can screen all qualified candidates, maximizing the validity of your hiring process.

    We follow the scientific literature and develop tests that best predict on-the-job performance. Our tests are scientifically validated so you can be confident they actually work.

    We recommend which assessments best suit your needs and advise you how to weigh the assessments to maximize predictive validity.

    We also offer a comprehensive assessment creation tool so you can develop your own assessments or import assessments you are already using.

    Responsibilities
    • participated in all meetings
    • Bubble development
    • JS integration
    • Forming links by passes relative to the user's route through the pages
    • Each user role has its own permissions that can be configured from the bubble side
    • There are also many other functions that I have highlighted the most interesting and complex functions
    • I took over the project after two previous teams and performed an extensive optimization and restructuring of both the database and UI elements. By streamlining the architecture, I achieved up to a 10x increase in performance in several areas, transforming a sluggish, unresponsive site into a smooth and user-friendly experience
    BubbleBubble APIStripeJavaScriptHTML / CSS / JSAPIREST API
    Automation

    Automation that pays for itself

    Real workflows I've automated — fewer manual steps, fewer errors, hours saved.

    Lead processing

    Set up automatic lead-card population for a company: submissions from Meta Lead Forms are parsed, every needed field is extracted and written straight into the CRM — zero manual data entry.

    N8NMeta Lead FormsCRM API

    Country from phone number

    The CRM had no country detection. I added an automation: the moment a phone number lands on a lead, the 'Country' field updates instantly from the dialing code.

    N8NCRM API

    Call processing & transcripts

    Integrated Sembly (AI call assistant): it records and transcribes each meeting, then an automation searches the CRM for an entity by participants' emails across types (lead, user, etc.). If found, the transcript is attached to it; if not, a Slack alert is raised for manual handling.

    SemblyN8NCRM APISlack

    CRM required-field guard

    Required-field validation was a paid-tier CRM feature — so I built my own. Weekly it scans every record across all data types; if fields are missing it tags each salesperson in Slack for their own records, listing exactly what to fix. Clean next week? No tag. Records can be marked 'ignore' straight from Slack.

    N8NCRM APISlack
    ✦ AI

    Personalized lead outreach

    Personalized email campaigns to hot and cold leads, where every message is generated by AI. The model is fed data pulled from the lead's LinkedIn profile together with notes and fields from the CRM, then writes copy tailored to the lead's stage and context. Segments come from the CRM; messages are sent and tracked through SendGrid.

    N8NOpenAILinkedInCRMSendGrid
    ✦ AI

    Auto lead scoring

    Every new lead is scored automatically by source, budget and reply speed, then sorted into hot, warm or cold. Sales see a ranked list and work the best leads first, no manual sorting.

    N8NCRM APIOpenAI

    Invoice and payment sync

    Paid invoices from Stripe update the linked CRM deal to “paid” and trigger a thank-you email. Overdue ones raise a reminder to the client and a Slack ping to the manager.

    N8NStripeCRM APISlackSendGrid

    Daily pipeline digest

    Each morning the team gets a Slack digest: new leads, stage changes, deals with no activity for X days and today's scheduled calls. Managers start the day knowing exactly what needs attention.

    N8NCRM APISlackOther APIs

    Stale lead re-engagement

    Leads with no reply for a set period are pulled automatically and sent a personalized re-engagement message tuned to their last stage. Responses route back to the rep, the rest stay in a nurture loop.

    N8NCRMPostmark

    Review and feedback collection

    After a deal closes or a project ships, the client gets an automatic request for feedback. Positive replies are routed to a public review link, critical ones go straight to the manager in Slack.

    N8NCRM APIPostmarkSlack
    ✦ AI

    AI research agent

    Give it a company or a lead, and the agent gathers public data, builds a short profile with industry, size and likely needs, and writes it straight into the CRM card before the first call.

    N8NClaudeWeb searchCRM API
    ✦ AI

    AI inbox agent

    The agent reads new emails, sorts them by intent, drafts replies for routine ones, flags anything that needs a human, and turns real requests into CRM leads or tasks automatically.

    N8NClaudeCRM APIGmail
    ✦ AI

    Multi-agent pipeline

    Several agents work as a team: one qualifies the lead, one researches it, one writes the outreach, one schedules the follow-up. Each hands off to the next, with a human approving only the final step.

    N8NClaudeCRM APISlack
    ✦ AI

    Hospitality — Guest check-in agent

    Bookings from any channel sync into one place. The system sends pre-arrival instructions, collects guest data, and an agent answers common questions (wifi, check-out, parking) in chat around the clock, escalating only real cases to staff.

    N8NClaudeBooking APIWhatsApp
    ✦ AI

    Hospitality — Review and reputation

    After check-out each guest gets an automatic feedback request. Positive replies are routed to public review sites, complaints go straight to the manager with a draft response, so issues are handled before they go public.

    N8NClaudeCRMEmail

    Logistics — Shipment tracking and alerts

    Every order is tracked across carriers. Delays, stuck parcels or failed deliveries trigger an instant alert to the client and the ops team, with the next action already suggested.

    N8NCarrier APIsSlackSendGrid
    ✦ AI

    Logistics — Route and load planning

    Daily orders are grouped by zone and an agent proposes an optimized route and load order, cutting empty mileage and manual planning. Drivers get the ready plan on their phone.

    N8NClaudeMaps APITelegram

    Retail — Stock and reorder guard

    Inventory is monitored across channels. When a product drops below threshold, the system drafts a reorder, flags slow movers, and warns about items about to sell out before a campaign.

    N8NCRM / ERP APISlack

    Retail — Price and competitor watch

    Competitor prices and your own catalog are checked on a schedule. Significant changes raise an alert with a suggested price move, so you react in hours, not weeks.

    N8NWeb scrapingSheetsSlack

    Finance — Invoice and payment reconciliation

    Incoming payments are matched to invoices automatically. Paid ones update status and send a receipt, overdue ones trigger a polite reminder chain and a manager ping.

    N8NStripe / Bank APICRMSendGrid
    ✦ AI

    Finance — Expense and document agent

    Receipts and invoices sent to one inbox are read by an agent that extracts amounts, dates and categories, writes them into the accounting sheet, and flags anything that looks off for review.

    N8NClaudeOCRSheets
    ✦ AI

    Real estate — Lead-to-viewing agent

    New property inquiries are qualified by an agent, matched to suitable listings, and offered viewing slots automatically. Confirmed viewings land in the agent's calendar with a reminder to the client.

    N8NClaudeCRMCalendar

    Healthcare / Services — Appointment flow

    Bookings, reminders and rescheduling run automatically. No-show risks get an extra nudge, freed slots are offered to the waitlist, and the front desk stops chasing confirmations.

    N8NCalendarWhatsAppCRM
    RAG / Knowledge

    RAG systems — chat with your own data

    Assistants grounded in your own documents — accurate answers with citations, nothing invented.

    ✦ AI

    Company knowledge assistant

    An assistant that answers from your own documents, wikis and past projects. Staff ask in plain language and get an exact answer with a link to the source, instead of searching folders. New hires get up to speed in days, not weeks.

    QdrantOpenAI embeddingsClaudeLangChainn8nCustom interfaceSelf-hosted
    ✦ AI

    Customer support bot

    A support bot grounded in your product docs, FAQ and past tickets. It answers real customer questions accurately, cites the source, and hands off to a human only when the answer is not in the knowledge base.

    PineconeOpenAI embeddingsClaudeLangChainn8nWeb widgetCustom interface
    ✦ AI

    Document Q&A

    Upload contracts, reports or manuals and ask questions in natural language. The system pulls the exact clause or figure and quotes where it came from, so nothing is invented.

    LlamaIndexpgvectorOpenAIOCRLlamaParseCustom interfaceSelf-hosted
    ✦ AI

    Sales and proposal helper

    An assistant that knows your pricing, case studies and past proposals. It drafts tailored offers and answers client questions using only your verified materials, keeping every claim on-brand and accurate.

    WeaviateClaudeOpenAI embeddingsLangChainn8nCustom interface
    ✦ AI

    Legal and compliance search

    Search across policies, regulations and internal rules by meaning, not keywords. The system returns the relevant passages with citations, so review is faster and traceable.

    QdrantCohere embeddingsClaudeLlamaIndexCustom interfaceOllamaSelf-hosted
    ✦ AI

    Personal / expert clone

    A chatbot trained on one person's content (courses, posts, transcripts) that answers in their voice and knowledge. Useful for creators, coaches and experts who want to scale their advice.

    ChromaOpenAILangChainn8nTelegramWeb widgetCustom interface
    Contact

    Let’s talk

    Open to freelance and full-time. Replies in English and Ukrainian.

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