Building healthcare software usually means assembling a FHIR data store, an identity provider, audit logging, and clinical interfaces before any product code gets written, and Medplum ships all of it as one open-source platform. Every clinical record, from patients and encounters to observations, medications, and appointments, lives in a standards-based repository you can query through REST and GraphQL APIs with full search parameters. Sign-in and permissions come built in through OAuth, OpenID Connect, and SMART-on-FHIR, with access policies that control read and write rights down to the resource, compartment, and field level. The included web app lets your team browse and edit any resource, manage project users, clients, bots, and secrets, and review a complete audit trail where every read, write, and login is recorded. Bots run your TypeScript logic inside the platform when resources change, on schedules, or over HTTP, handling jobs like HL7 transforms, eligibility checks, and notifications without another server to operate. Subscriptions push real-time events to your services through webhooks or WebSockets with retries and signing, and projects partition data so each clinic or customer stays isolated on one deployment. Clinicians get ready-made interfaces for charting, scheduling, eligibility, and billing that you can fork and rebrand, while patients reach their records through portals and SMART health links. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache-2.0 licensed.

Mere Medical pulls the records from every hospital and clinic patient portal you use into one date-ordered timeline, so lab panels, immunizations, and procedures from different systems sit side by side. Each timeline card shows its facility and, when recorded, the provider, and expands with View More; a Jump To index leaps between years. The Summary tab condenses bookmarked labs, medications, conditions, immunizations, care plans, and allergies onto one dashboard whose cards can be dragged into any order or hidden. Lab results are graphed over time wherever the units line up, and a search bar finds specific entries by keyword. Connections sync from Epic MyChart, Oracle Health (Cerner), Veradigm, DrChrono, eClinicalWorks Healow, athenahealth, and NextGen, and several sources can feed one profile at once. Everything lives on your device, so records stay searchable offline and no account sign-in is needed; an optional password encrypts them at rest. Separate user profiles hold each person's records, and JSON export and import make backups simple. Experimental AI features add semantic search that links a phrase like high blood sugar to related labs, plus a Mere Assistant that answers plain-language questions about your records using local Ollama models or an OpenAI key. Install it on a phone or desktop home screen for quick access in the waiting room. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Your medical history, fragmented across a dozen patient portals, in one place on your server: MediKeep (formerly Personal Medical Records Keeper) is a self-hosted health record system. Built with a React frontend and FastAPI backend over PostgreSQL, it organizes 14 categories of medical data - medications with dosages and schedules, conditions, procedures, allergies, immunizations, symptoms, injuries, doctor visits and encounters, treatments, lab results, and even medical equipment with service dates and supplier info. Treatment management is genuinely sophisticated: an advanced mode links treatments to their medications with per-medication overrides for prescriber, pharmacy, and effective dates, and reverse lookup shows which treatments use a given medication. A dashboard summarizes records and recent activity, file uploads attach documents to records, and tagging works across categories. When a new specialist asks for your history, the report builder assembles custom reports by category and exports to PDF, JSON, or CSV - a curated, portable summary instead of a folder of photocopies. Authentication supports Google and GitHub SSO with OIDC providers like Keycloak and Authelia expected to work, and the built-in backup system protects the archive. Health data is exactly what should never live in someone else's cloud.

Service businesses get a booking page without per-booking commissions or monthly SaaS fees from Easy!Appointments, the self-hosted appointment scheduler. Customers pick a service, provider, and open time slot from a clean web form; the system enforces working plans, breaks, and booking rules you define per provider, then confirms by email to both sides. The structure fits real service organizations: multiple providers with individual schedules, multiple service types with their own durations and prices, and admin/secretary roles for front-desk management. Two-way Google Calendar synchronization keeps each provider's external calendar authoritative - book in Easy!Appointments and it appears in Google Calendar, block time in Google and the slot disappears from the booking form. Version 1.6 adds SMS notifications and payment support, and a REST API opens the scheduling data to custom integrations. Built on PHP (CodeIgniter) with MySQL, it installs in a single folder and can share a database with your existing site; a WordPress plugin embeds the booking form directly in pages or posts. The interface ships in dozens of languages with time-zone handling throughout. GPL-3.0 licensed and free for commercial use - a helpdesk, clinic, salon, or consultancy runs its whole booking workflow on its own server.

With over 47,000 GitHub stars, Cal.diy is the fully open-source community fork of Cal.com that strips away every proprietary license gate and enterprise paywall to deliver a pure MIT-licensed scheduling platform you completely own. The booking engine supports individual event types including recurring events, seated events with capacity limits, and paid bookings through Stripe and PayPal, all backed by customizable availability schedules with date overrides, buffer times, minimum notice periods, and travel schedule support. Calendar synchronization is bidirectional across nine providers — Google Calendar, Outlook and Office 365, Apple Calendar, CalDAV, Lark, Feishu, Zoho, Exchange, and ICS feeds — so every booking automatically appears on your existing calendar while blocking conflicting slots. Video conferencing links generate automatically for Zoom, Google Meet, Microsoft Teams, Webex, Jitsi, Daily.co, Whereby, and Huddle01, eliminating manual link management. The automation layer connects through webhooks, Zapier, n8n, Make, and Pipedream to CRM platforms like HubSpot, Salesforce, and Close, messaging services including Discord, Telegram, and WhatsApp, and analytics tools such as Google Analytics 4, PostHog, and Fathom. The entire application is built on the T3 stack — Next.js for server-rendered pages, tRPC for end-to-end type-safe APIs, Prisma for PostgreSQL database access, and Tailwind CSS for the responsive interface. Unlike Cal.com's open-core model, Cal.diy requires no license key and includes no gated features. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Freelancers, contractors, and small shops can turn a short form into a client-ready PDF invoice, with a live preview that redraws on every keystroke and no account to create. Fill in seller and buyer details, then add line items with quantity, unit, net price, and tax rate; net amounts, tax, totals, and the amount in words are calculated automatically. Item discounts take a percentage or fixed amount off any line under a custom label, and tax applies to the discounted figure. Pick a classic layout or a Stripe-style template, and add your logo as a JPEG, PNG, or WebP file. Invoices can be written in 13 languages, including Brazilian Portuguese, with 122 currencies, 18 date formats, and a number format setting that survives a language switch. Tax labels can read VAT, GST, Sales Tax, or anything else, or the tax columns can be dropped entirely. Bank account, SWIFT/BIC, payment method, due date, and notes sit alongside an optional QR code that can carry a payment link, UPI details, or contact information. Long invoices flow onto extra pages automatically. Saved seller and buyer profiles fill in the next invoice for you, and the data stays in the browser. Download the PDF or copy a shareable link that opens the same invoice for your client. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.

Roughly 40 integrated business apps forming a full ERP: Odoo's open-source suite runs companies end to end. The Community Edition, licensed LGPL-3.0, ships roughly 40 apps covering CRM, sales, invoicing, basic accounting (journals, chart of accounts, taxes, reconciliation), inventory and warehouse management with multi-step routes, manufacturing with BOMs and work orders, purchasing, project management, timesheets, HR, a website builder, and eCommerce. Each app works standalone, but they share one PostgreSQL database and one data model, so a confirmed sale updates stock, triggers procurement, and posts invoices without integration glue. The modular design means you enable only the apps you need and extend with 40,000+ community modules from the Odoo app store covering nearly any vertical requirement. Inventory supports multi-warehouse stock, reordering rules, and lot and serial tracking with barcode-ready operations; manufacturing ties BOMs, work orders, and work-center routing directly to sales demand and stock levels; and the website builder sells straight from your product catalog with payment provider integrations. You can start with just CRM and invoicing on day one and switch on inventory or eCommerce later - new apps integrate with existing data instantly because the schema is shared. The server is Python with an XML/JavaScript view layer, and because data lives in plain PostgreSQL there is no proprietary format: you can query, back up, migrate, and extend business data directly, with unlimited users and no per-seat licensing - where enterprise ERP pricing is per user per month, headcount here costs nothing.

With over 37,800 GitHub stars and active development since its first release in 2008, ERPNext is the most-starred open-source ERP system — delivering accounting, inventory management, manufacturing, CRM, project tracking, asset management, HR, and point-of-sale capabilities through a unified web interface built on the Frappe Framework's metadata-driven architecture. The accounting module handles multi-company consolidation, multi-currency transactions, tax templates for GST and VAT, bank reconciliation, and automated journal entries with real-time profit and loss, balance sheet, and cash flow reporting. Manufacturing covers production planning with multi-level bill of materials, work order scheduling, capacity planning, subcontracting, and quality inspection at each production stage. Inventory tracks stock across multiple warehouses with batch and serial number tracing, automatic reorder levels, landed cost calculations, and perpetual inventory valuation using FIFO or moving average methods. The CRM module manages leads, opportunities, and customer communication with email integration, while project management tracks tasks, timesheets, and Gantt-based scheduling with budget controls. Custom applications extend functionality through the Frappe ecosystem without forking the core codebase, and the REST API enables integration with payment gateways, shipping providers, and third-party services. Deployable via Docker Compose or the bench CLI tool with MariaDB and Redis. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.

OpenResto is a self-hosted booking system that lets restaurants, bars, and cafes take reservations from their own website instead of paying a platform for every cover. Guests browse your locations, pick a party size, date, and time, and the exact table is held for five minutes while they type a name and email, with no account to create and nothing to install. Slots are grouped into Lunch, Dinner, and Off-Peak so guests jump straight to the sitting they want, and confirmation pages offer calendar export, reminders, and directions. Staff run the night from a dashboard with a live bookings list, a day timetable, and a service view, extending or cancelling reservations and pausing new bookings during private events without editing any configuration. One instance manages several restaurants, each with its own floor sections such as Patio or Bar, opening hours in its own timezone, policies, and pacing rules. The whole guest experience carries your name, colors, and icon, and the same screens can even be published as your own phone app. Every admin action lands in an append-only activity trail, and scoped API keys let your other tools read bookings without ever seeing guest contact details. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.