Salesforce's core workflow, open-source and on your own server: Twenty is a modern CRM built as exactly that alternative. It ships the standard CRM objects out of the box: people, companies, opportunities, notes, and tasks, displayed in table and kanban views with drag-and-drop and real-time updates. Its defining technical feature is a metadata-driven data model: you define custom objects and fields in the UI, and the backend regenerates its GraphQL schema at runtime, so a new object gets working queries, mutations, filters, and sorting within seconds, with no migrations to run - adapting the CRM to your sales process never requires code changes. A REST API is auto-generated from the same schema, GraphQL subscriptions push real-time updates, and webhooks fire on record changes for external integration. A visual workflow builder automates actions like notifications and field updates, TypeScript-based apps extend the platform with custom logic and frontend components, and email and calendar sync pulls Gmail messages and meetings onto contact timelines so communication history sits next to the record. The stack is NestJS with TypeORM, PostgreSQL, Redis, and BullMQ on the backend, React with Jotai on the frontend. Self-hosting on RepoCloud means unlimited users with no per-seat licensing - the pricing model that penalizes growing teams on commercial CRMs - and your pipeline, contacts, and deal history live in your own PostgreSQL database rather than a vendor's.

CRMs, project trackers, inventory tools - NocoBase is an open-source no-code/low-code platform for building business systems like these. Its architecture is data-model driven: you define collections and relationships first, then compose any number of interface blocks (tables, forms, kanban, charts) on top of the same model, so data structure is never coupled to a particular view. The core is a microkernel where every feature is a plugin, WordPress-style; you enable official plugins, install marketplace ones, or write your own as npm packages with server and client parts. Data sources include the main PostgreSQL or MySQL database, external databases, and third-party APIs - so you can build admin panels over existing production data instead of migrating it. Built-in infrastructure covers role-based permissions down to collection, record, and field level, workflow automation with approval steps and scheduled triggers, and audit logs; a one-click switch flips between usage and configuration modes. Because custom features live in isolated plugins with a documented lifecycle, core upgrades do not overwrite your customizations, and swapping UIs never requires data migrations since interfaces sit on independent models. Written in TypeScript on Node.js, Koa, and React under the AGPL license, it is light enough for one person to run and extend - and where no-code SaaS platforms charge per seat and per app, a self-hosted instance runs unlimited applications for unlimited users at hosting cost alone.

Bigcapital gives small and medium businesses a complete double-entry accounting, invoicing, and inventory management platform they can self-host for free, replacing the per-seat subscriptions of QuickBooks, Xero, and Wave. Every transaction records debits and credits across your chart of accounts, automatically generating balance sheets, profit and loss statements, trial balances, general ledger reports, journal entries, accounts receivable and payable summaries, cash flow analysis, inventory valuation, and inventory summary reports. Sales invoicing supports recurring schedules, customer payment tracking, estimate-to-invoice conversion, and configurable GST/VAT tax rates. Purchase invoicing handles vendor bills with expense categorization for payroll, rent, and operational costs. The inventory module tracks stock levels using FIFO and average cost methods, automatically adjusting quantities on every sale or purchase and providing reorder alerts. Multi-currency accounting converts transactions at real-time exchange rates and consolidates them under customer or vendor profiles with detailed currency reports. The platform deploys via Docker Compose with multi-tenant isolation giving each organization its own separate database, requiring as little as 2GB RAM for the complete production stack. A headless REST API with Postman collections lets developers embed the accounting engine into external applications for programmatic transaction management. Role-based permissions control access for team members and invited accountants across organizations. 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.

InvoicePlane manages the complete freelance and small-business billing cycle — draft quotes, convert them to invoices, automate recurring charges, collect payments through Stripe and PayPal, and generate EU-compliant eInvoice XML for automated processing by accounting systems. Deployed over 100,000 times across 193 countries, the PHP 8.2+ application on CodeIgniter 3 with MySQL or MariaDB handles everything from first estimate to final receipt. EU-compliant eInvoice generation creates machine-readable XML invoices meeting European Union standards since version 1.6.2. Recurring invoices automate periodic billing with configurable controls that pause generation when previous invoices remain unpaid. Online payment integration lets clients pay directly through Stripe, PayPal with Advanced Credit Cards, and Venmo support. The CRM-like client management module stores contact details, notes, custom fields, and complete transaction history per client. Product and task management modules let you build line-item invoices from reusable product catalogs and project tasks. Customizable PDF templates powered by mPDF support branded invoice layouts with QR codes, while email delivery via PHPMailer handles automated sending with configurable SMTP. A guest portal gives clients read-only access to view and pay their outstanding invoices and quotes. Financial reporting tracks revenue, outstanding balances, and payment history. The multi-language interface supports community translations, and multi-currency handles international invoicing. Deploy via Docker Compose with automatic database migrations. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Salesforce's platform model, 100% open-source (Apache 2.0): Corteza is a Go/Vue.js low-code platform developed under a foundation, so there is no open-core bait to grow out of. The heart is Corteza Compose: namespaces contain applications, modules define record structures the way Salesforce objects do, and a drag-and-drop page builder assembles record pages, list pages, dashboards, and charts from configurable blocks. Automation comes from a visual, BPMN-style workflow engine plus JavaScript automation scripts, so cross-application business logic - approval chains, field updates, notifications - is configured rather than programmed. Granular role-based permissions reach down to individual modules, fields, and records, mirroring real organizational hierarchies. Corteza CRM ships as the flagship application built entirely on Compose: leads, accounts, opportunities, campaigns, and cases with a 360-degree customer view, covering most Salesforce standard objects - and because it is just a Compose app, adding or reshaping modules is configuration, not a fork. Everything is reachable over REST APIs, deliberately familiar tooling eases Salesforce admin migration, and a CLI can even generate synthetic records for load-testing what you build.

Unlimited agents, unlimited tickets, unlimited mailboxes, forever, on a $4 VPS - FreeScout's pricing inversion is why it became the most popular self-hosted Help Scout alternative, a PHP/Laravel help desk and shared inbox developed from scratch over eight years. The inbox deliberately behaves like Gmail or Outlook, so new support agents need close to zero training. The email-support core is genuinely complete: seamless IMAP/SMTP integration including modern Microsoft Exchange authentication, collision detection that warns when two agents open the same conversation, canned responses, auto-replies, internal notes, open tracking, starring, forwarding, merging, and moving conversations between mailboxes, phone-call logging, push notifications, and an auto-refreshing conversation list - plus screenshot pasting straight from the clipboard into replies. It's 100% mobile-friendly, fully screen-reader accessible, and translated into 28 languages. Beyond the core, an ecosystem of 100+ modules (mostly one-time $12-20 purchases) adds knowledge base, workflows with Gmail-filter-style automation rules, satisfaction ratings, time tracking, tags, custom fields, LDAP, Slack, WhatsApp and Telegram channels, and an API with webhooks - pay only for what your team needs. Web installer and updater included. AGPL-licensed.

Teams tired of paying Salesforce or HubSpot per seat run EspoCRM: an AGPL-licensed PHP application with a fast single-page frontend over a REST API, covering sales, support, and marketing in one uncluttered interface. The sales core is complete - leads, contacts, accounts, opportunities with customizable pipeline stages, kanban views, calendars, meetings, and calls. Email is deeply integrated rather than bolted on: IMAP sync links messages to CRM records automatically, and mass email campaigns run with reusable templates, tracking, and Web-to-Lead forms feeding the funnel. Support teams get case management and a customer portal where clients track their own tickets and access a knowledge base. The real differentiator is the Entity Manager: create custom entities, fields, relationships, and layouts from the admin UI without code, with dynamic logic showing or hiding fields conditionally - EspoCRM is as much a business-application platform as a CRM. Formula scripting handles calculated fields and record automation in the free core; the optional Advanced Pack adds visual BPM process design and workflow rules. Role-based permissions with team and territory scoping, full-text search, reports, and a straightforward REST API for n8n or custom integrations round it out. Runs on PHP 8.3+ with MySQL, MariaDB, or PostgreSQL - unlimited users, zero per-seat fees.

Horilla HRMS gives a growing company one home for the whole employee journey, from the first job posting to the final payslip, instead of five disconnected HR tools. Recruiters publish openings, collect resumes, and drag candidates through a Kanban hiring pipeline with interview scheduling and email built in; the moment someone is hired, structured onboarding checklists take over. Every employee record lives in one directory with documents, job history, and reporting lines, and staff help themselves through a self-service portal for leave requests, attendance views, and payslip downloads. Attendance arrives from biometric devices, mobile check-ins, or geo-fenced punches, and leave balances update themselves as approvals flow through managers. Payroll then reads that same attendance and leave data, applies your salary structures, overtime rules, loans, and statutory deductions, and generates itemized payslips in a single run. Managers set goals, run review cycles, and collect continuous feedback in the performance module, while the asset register tracks every laptop and phone issued to the team. An internal helpdesk queues employee requests with priorities and assignees, offboarding workflows make sure exits are as orderly as arrivals, and LDAP integration ties accounts to your existing directory. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. LGPL-2.1 licensed.

With over 13,000 GitHub stars and active monthly releases, Mailcow delivers a production-ready mail server infrastructure through Docker Compose orchestration of twelve integrated containers. The stack pairs Postfix as the MTA handling SMTP traffic with Dovecot for IMAP and POP3 retrieval featuring the Flatcurve full-text search engine, while Rspamd provides machine-learning-powered spam filtering with Bayesian classification, DKIM signing, and ARC support. ClamAV scans attachments for malware including Office document macro analysis via Olefy, and SOGo serves as a responsive webmail client with CalDAV, CardDAV, and Microsoft ActiveSync synchronization. The admin panel manages multiple domains, per-user spam score thresholds, quarantine review, black and whitelists, temporary spam aliases, mailbox quotas, and TLS enforcement policies for both inbound and outbound messages. Security features include two-factor authentication via TOTP, WebAuthn, and Yubikey OTP, a Fail2ban-like Netfilter integration for brute-force protection, and automatic SPF, DKIM, and DMARC configuration. The ACME container handles Let's Encrypt certificate generation with DNS-01 challenge support, while Postfix TLS-Pol provides MTA-STS and DANE/TLSA resolution for encrypted transport. Built-in imapsync enables periodic migration from remote mailboxes, and the REST API allows programmatic management of all server resources. MariaDB stores user data, Redis caches configuration and sessions, and Unbound provides local DNSSEC-validating DNS resolution. 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.

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.

SOGo adds shared calendars, address books, and a modern webmail interface to your existing Dovecot, Postfix, or Cyrus mail setup, turning familiar infrastructure into a full Exchange competitor. Rather than replacing your IMAP and SMTP servers, SOGo layers collaboration on top of them, becoming the missing link between raw mail delivery and what users actually expect from a workplace communication platform. The ActiveSync implementation synchronizes email, contacts, calendars, and tasks natively with iPhones, Android devices, and Windows without requiring users to manually configure CalDAV endpoints. CalDAV and CardDAV compliance ensures Apple Calendar, Thunderbird (via the official SOGo Connector extension), GNOME Evolution, and Android via DAVx5 all connect without plugins or workarounds. The web interface uses AngularJS Material design with responsive layouts, offering folder management, drag-and-drop calendar scheduling, contact groups, resource booking, and delegation. Shared calendars support free-busy lookups, iMIP event invitations, and per-user ACL permissions for fine-grained access across organizational units. Built on Objective-C with the GNUstep foundation, SOGo delivers exceptional performance: hundreds of concurrent ActiveSync connections from mobile devices alongside webmail and calendar traffic with sub-second response times. With 2,095+ stars and 116 releases, the project has proven its stability in production environments supporting thousands of users. The Docker deployment runs alongside PostgreSQL and memcached.

With 6,800 GitHub stars and over a decade of development since its 2014 release, ONLYOFFICE Docs delivers a self-hosted Microsoft Office replacement with pixel-perfect OOXML rendering and real-time collaborative editing supporting both Fast (character-by-character) and Strict (manual save) co-authoring modes. The suite encompasses five full-featured editors — Document Editor for DOCX/ODT/EPUB/HTML, Spreadsheet Editor with 500+ functions and pivot tables, Presentation Editor with animations and transitions, Form Creator for fillable PDF forms with field validation, and PDF Editor for annotation and conversion — all operating within a unified web interface. Format support spans 50+ types including DOCX, XLSX, PPTX, ODT, ODS, ODP, PDF, CSV, RTF, TXT, and Markdown with server-side conversion between any supported pair. The JavaScript plugin API enables extending editor functionality through a marketplace of ready-made plugins for ChatGPT integration, speech-to-text, OCR, Zotero citations, and Thesaurus. Ready-to-use connectors integrate with Nextcloud, ownCloud, Seafile, Moodle, Odoo, Confluence, SharePoint, Alfresco, Liferay, and Chamilo, while WOPI protocol compliance enables integration with any WOPI-compatible platform. JWT authentication secures all API communications between host applications and the document server. Deploy via Docker with a single command or DEB/RPM packages on Ubuntu, Debian, CentOS, or RHEL. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GNU AGPL v3 licensed.

GroupOffice checks your whole company in at one address: mail, meetings, projects, invoices, and files behind a single login on your own server. The built-in mail client saves messages straight onto projects or contacts, signs and encrypts with S/MIME, and shares folders and accounts across the team. Shared calendars offer team views, bookable resources, and video meetings, while address books carry custom fields and comments so customer knowledge survives staff changes. Projects gather their tasks, files, and discussions in one place, track hours as work happens, and turn those hours and costs into invoices and reports. Support tickets arrive from your website or by email and stay organized by team, and newsletters compose campaigns from templates filled with your own data. Files co-edit in the browser through OnlyOffice or Collabora, connect to desktops over WebDAV, and sync to native phone and computer apps over open protocols. Two-factor authentication, encryption, and a module system you can extend with your own tools keep the office private and shaped to how you actually work. 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.

jshERP lets a small or midsize business, from a shop to a wholesaler, run purchasing, stock, sales, and money from one place instead of scattered spreadsheets. A purchase requisition becomes a purchase order, then a receipt that raises stock. A sales order becomes an outbound delivery that lowers it, or a purchase order when more must be bought in. Retail sales, returns, and serial-number scanning run through the same stock. Products sit in a category tree up to three levels deep, with barcodes, images, multiple attributes, customer-specific prices, and a base unit plus up to three secondary units. Transfers move goods between warehouses, assembly and disassembly merge and split products, and shelf locations record where each item sits. Other receipts and issues cover opening stock, stocktake corrections, and scrapped goods, while moving-average cost keeps valuation current. Finance logs income, expenses, receipts, payments, transfers, and prepayments against settlement accounts, and customer and supplier reconciliation reports export to Excel. Reports track stock levels, low-stock alerts, in-out statistics, and purchase and sales summaries, and the home page totals yesterday's and retail sales. Roles limit access down to single menus and buttons and can mask prices. A tenant model runs several businesses on one installation, and the interface switches among 73 languages. 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.

Spreadsheets and old Access databases give way to custom business apps that a team builds itself in a browser with Saltcorn, a no-code database application builder. Tables hold related records with typed and calculated fields, and CSV files import straight into them. Views start from patterns such as list, show, edit, filter, kanban, calendar, gantt, map, and chart, then take shape on a drag-and-drop canvas with a layers tree and desktop, tablet, and mobile previews. A view can embed another view, so clicking a row narrows the others and builds a cross-filtering dashboard with no glue code. Triggers react to row changes, schedules, logins, and API calls, while visual workflows branch, loop, and pause for a person's form before resuming days later. An AI copilot drafts tables, pages, and workflows from a plain-language prompt. The same views also become native Android and iOS apps with offline mode, PDF or image documents, and responsive emails. Every table, view, and page carries a minimum user role, and an auto-generated REST API exposes the data. Packs such as project management and an address book start an app from a ready template. 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 customer relationships deserve better than a spreadsheet and a prayer: SuiteCRM gives sales, support, and marketing teams one shared system for every account, contact, lead, and deal. Track opportunities through your pipeline with stages, amounts, and close dates, then quote and invoice directly from the won deal without retyping a single line item. Support agents work cases with queues, assignments, and email threading, while marketers build target lists, run email campaigns, and measure opens and clicks against the same records sales uses. Reports query across any modules with grouping, aggregation, and charts, export to CSV or PDF, land on dashboards as dashlets, and arrive by scheduled email so Monday's pipeline review writes itself. Workflow rules react to record changes by sending notifications, creating tasks, updating fields, or calling webhooks, quietly handling the follow-up work humans forget. Roles and security groups decide exactly which teams see which records, down to individual fields, and the audit log remembers every change. Administrators reshape the system without code in Studio, adding fields (including image and file fields), rearranging layouts, and building whole custom modules, while the REST API connects SuiteCRM to your website forms, telephony, and accounting tools. 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.

A deliberately simple ticketing system standing in for both Zendesk and Jira: Peppermint handles internal staff requests and external customer support alike. The stack is modern full-stack TypeScript: Next.js and React over Prisma and PostgreSQL, which makes it light to run and approachable for developers extending it. Ticket creation is straightforward - a markdown editor with file uploads, assignment, status tracking, and a logical workflow that new agents grasp without a manual. Mailbox integration converts email into tickets automatically: configure SMTP/IMAP per mailbox and incoming messages become trackable tickets. Each client accumulates an interaction history, giving agents context on every past request before replying. Two touches distinguish it from bare-bones ticketing: a built-in markdown notebook with todo lists for internal documentation and knowledge sharing, and OIDC authentication so agents sign in through your existing identity provider - Keycloak, Okta, Authentik, or Azure AD. Configurable webhooks and email notifications push ticket events to third-party services. The UI is responsive from mobile to 4K, and everything works fully offline in air-gapped environments. Docker-native and scalable via Kubernetes, with an active community of 3,000+ GitHub stargazers.

With 7,400+ GitHub stars, 280+ contributors, and 99 releases spanning 15 years of active development since 2011, Dolibarr is the modular ERP and CRM platform that scales from freelancers tracking invoices to manufacturing companies managing full production workflows — all within a single PHP application requiring only a web server and database. Enable exactly the modules your business needs: CRM with leads, proposals, and online contract signing; invoicing with customer and supplier management, credit notes, and SEPA direct debit; double-entry accounting with bank reconciliation and margin analysis; stock and warehouse management with barcode scanning, batch and lot tracking, and product variants; bill of materials and manufacturing orders with workstation scheduling; HR with employee records, leave management, expense reports, recruitment pipelines, and timesheets; project and task management with shared iCal calendars; and a ticket system with integrated knowledge base for customer support. TakePOS provides a touch-optimized point-of-sale interface for retail shops, bars, and restaurants with floor and table management, QR code self-ordering, automatic stock decrements, and Stripe terminal integration. Payment processors connect via PayPal, Stripe, and Paybox. The marketplace offers over 1,000 third-party add-ons, and the low-code Module Builder enables custom extensions without programming. Deploy via the official Docker image with MariaDB, DEB and RPM packages for Linux, or manual installation on any PHP-capable server. 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.