Full-stack SaaS developer

    Dylan Buchi

    I build focused SaaS products and product-grade web apps: sharp Next.js interfaces, typed backends, integrations, auth boundaries, and the release discipline to make small systems trustworthy.

    Next.jsTypeScriptSaaS systemsAuth & permissionsLaunch checks
    Evidence over adjectives

    What you get.

    I am a self-taught software engineer focused on the part of development where product judgment, implementation quality, and release readiness meet. I build with React, Next.js, TypeScript, Python, PostgreSQL, and the surrounding stack needed to ship useful web products.

    Current proof
    Built and deployed a controlled-access bookkeeping workflow SaaS with auth, integrations, storage, billing flow checks, and launch gates.
    Release discipline
    Tests and manual proof steps across permissions, public links, uploads, CSV safety, provider boundaries, and production smoke checks.
    Public history
    100+ public GitHub repositories, internship experience, freelance work, open-source contributions, and 50+ learning builds.

    Build narrow products that can actually ship

    I prefer focused workflows over broad platforms: one painful business process, clear boundaries, and enough product discipline to avoid fake scope.

    Make trust boundaries visible in the product

    Auth, roles, client links, uploads, billing, provider APIs, and public routes need explicit behavior, not vague "it should be fine" assumptions.

    Keep learning tied to real delivery

    My older public projects show range; the current direction is turning that range into deployable SaaS systems with clearer release proof.

    Experience

    Built under pressure.

    The strongest signal is the current SaaS work: product definition, interface design, backend wiring, integration boundaries, deployment, testing, and launch-readiness proof handled end to end.

    Independent Full-Stack Developer / SaaS Builder

    Private product studio / Substantly
    Sep 2024 - Present
    Geneva, Switzerland - Remote

    • Built and deployed a controlled-access SaaS for bookkeeping firms to collect explanations and receipts for uncategorized QuickBooks Online transactions.
    • Implemented firm-scoped auth, owner/admin/staff permissions, secure client response links, receipt uploads, reminders, review queues, CSV import/export, and gated access.
    • Integrated read-only QuickBooks Online import, Stripe sandbox billing flows, Resend transactional email, S3-compatible object storage, and Vercel production checks.
    • Created launch-readiness proof around QBO no-write-back boundaries, CSV formula safety, public-link access, receipt storage, scheduler authorization, billing containment, backup/restore, and browser smoke checks.

    Software Engineer Intern

    acheteur.ch
    Jun 2024 - Aug 2024
    Lausanne, Switzerland - Hybrid

    • Contributed React and Next.js components to a shared TypeScript monorepo for a large-scale real estate application.
    • Implemented Figma-based UI with reusable component patterns and strong attention to visual fidelity.
    • Worked in an Agile workflow to deliver frontend features, refactors, and component improvements.

    Self-Taught Software Engineer

    Independent study and projects
    Jul 2019 - Jun 2024
    Geneva, Switzerland

    • Built 50+ projects with React, Next.js, Python, Node.js, databases, and automation while studying full-stack development, data structures, and system design.
    • Completed 30+ online courses, delivered freelance work, and developed a practical habit of learning through shipped artifacts.

    Open Source and Freelance Work

    The Algorithms / SwissBorg
    2020 - 2021
    Remote

    • Merged 13 Python pull requests into The Algorithms, improving type annotations and resolving mypy dependency issues.
    • Built a SwissBorg Discord bot with automated responses, admin controls, uptime checks, and data-backed command handling.
    Selected work

    Best proof first.

    The strongest work is the current SaaS build. Public repositories still matter, but they are supporting evidence next to real product definition, trust boundaries, and deployment proof.

    Controlled access

    Workflow

    QBO transaction clarification

    ImportRequestReviewExport

    Controlled-access SaaS

    Substantly

    A focused bookkeeping workflow product for collecting explanations and receipts on uncategorized QuickBooks Online transactions without writing back to QuickBooks.

    • Firm-scoped owner/admin/staff permissions
    • Secure client response links, receipt uploads, reminders, and review queues
    • Read-only QuickBooks Online import, CSV import/export, and no-write-back boundaries
    • Stripe sandbox billing flows, Resend email, private object storage, health checks, and launch gates
    Next.jsTypeScriptPostgreSQLSQLiteQuickBooks OnlineStripeResendS3/R2 storageVitestPlaywrightVercel

    Public product visuals

    The transaction wedge is visible.

    Clean Substantly screenshots from the public product surface, using illustrative sample data only. They show the queue, client clarification loop, and review-before-export flow without private records, tokens, or customer data.

    Substantly public product screenshot showing a read-only uncategorized transaction queue
    Read-only transaction queueA focused QBO clarification queue keeps the product promise narrow: ask for context, collect proof, review before export.
    Substantly public product screenshot showing read-only import, secure client link, and review queue cards
    Clarification loopThe workflow shows import, secure client request, review status, and CSV readiness without fake analytics or sensitive data.

    Problem

    Bookkeeping firms still chase unclear QuickBooks transactions through email and spreadsheets, while clients need a low-friction way to answer without QuickBooks access.

    Workflow

    Import transactions, choose what needs context, send secure client links, collect explanations and receipts, review answers, then export clean CSV results.

    Trust boundary

    QuickBooks Online import is read-only. Substantly does not write categories back, attach receipts to QBO, auto-categorize with AI, or replace practice management.

    Production posture

    Signup is gated, request access is manual, production rejects local storage/database fallbacks, and hosted operation uses Postgres, private object storage, email, scheduler auth, and health checks.

    Private SaaS prototype

    SoloFocus

    A CRM-style SaaS prototype exploring Gmail and Google Contacts integrations, Stripe billing, scheduled workflows, and a PostgreSQL/Prisma architecture.

    Next.jsTypeScriptPostgreSQLPrismaStripeGoogle APIs
    Private prototype

    Private developer tooling

    Codex Workflow Kit

    A repo-native workflow layer for auditable AI-assisted coding: task state, briefs, handoffs, review and test evidence, closeout gates, package hygiene, and bounded proof commands.

    Node.jsCLI toolingGit hooksWorkflow stateTest gatesPackage hygiene
    Private prototype
    Travelio project screenshot

    Full-stack booking experience

    Travelio

    A marketplace-style stays app with profiles, property management, favorites, reservations, and trip tracking. The value is in the full workflow, not a static landing page.

    Next.jsReactTypeScriptMongoDBPrismaTailwind CSS
    Big Movies project screenshot

    Front-end product surface

    Big Movies

    A movie discovery app with auth, search, watchlists, favorites, trailers, and actor bios using the TMDB API.

    ReactReduxTypeScriptMaterial UITMDB API
    Folder Synchronizer project screenshot

    Python automation utility

    Folder Synchronizer

    A one-way source to replica folder sync tool built around predictable file operations, logging, and command-line practicality.

    PythonFile I/OCLIAutomation
    Stack map

    Tools with a job.

    The useful signal is not a long list of names. It is the ability to connect interface polish, server behavior, data modeling, integrations, deployment, and release checks around one narrow product workflow.

    Interface systems

    Next.jsReactTypeScriptTailwind CSSshadcn/ui

    Backend logic

    Node.jsServer-side authREST APIsSchedulersPythonFlask

    Data and storage

    PostgreSQLSQLiteMongoDBPrismaCSV workflowsS3/R2 storage

    Integrations

    QuickBooks OnlineStripeResendOAuthGoogle APIs

    Quality and release

    PlaywrightVitestVercelHealth checksBackup rehearsalSecurity headersWorkflow evidence

    Product range

    SaaS MVPsClient workflowsOpen sourceAutomationFigma implementation
    Ask this portfolio

    Get the signal fast.

    A constrained assistant for recruiters, clients, and collaborators. It answers from selected evidence instead of pretending to know everything.

    Source-limited answers
    Hiring, project-fit, and proof questions

    Portfolio briefing assistant

    Curated mode - no personal-data memory

    Grounded

    Ask a hiring or project-fit question. I will answer only from Dylan’s resume, portfolio, and selected project evidence.

    Curated portfolio data
    Contact

    Bring a workflow problem.

    I am most useful when a product needs to move from fuzzy idea to working system: SaaS MVPs, interface cleanup, auth and permissions, API integrations, automation, launch checks, or a second set of engineering eyes.