Huly, ERPNext + Frappe and Ever Gauzy are the truest do-everything references; Cal.com and Plane are the approachable ones
Asked:
“What are the best open source projects similar to Macro and Twenty in that they do a bit of everything and are good references to build your own projects with?”
Ten reference projects, consolidated from a 40-row shortlist of repository evidence (duplicate forks and mirror pages folded into canonical repos) and corroborated against 637 broad rows spanning 288 distinct hosts. Research ran 2026-09-20 across 1,517 unique web results before semantic filtering. Breadth here counts how many of 13 production patterns — auth, permissions, multitenancy, APIs, webhooks, queues, integrations, plugins, billing, observability, tests, CI, self-hosting — each codebase demonstrates; it is not a quality score.
The landscape in four tiers: breadth of production patterns per project
Bar length = production patterns demonstrated, out of 13. Tier colour marks the role each project plays as a reference, not a ranking. Hover or tap a bar for scope, stack and caveats.
What the tiers cannot say alone
Huly is the closest peer to Macro in product breadth (chat, projects, CRM, HR/ATS with realtime collaboration), but its repo carries the notice “Hosted Huly is shutting down — please migrate your data” — a real product-risk caveat for anyone betting on it. github.com
ERPNext plus the MIT-licensed Frappe Framework is the best mature app-plus-framework pair: the app covers accounting, orders, manufacturing, assets and projects while Frappe supplies permissions, admin UI, REST APIs, forms and a report builder. github.com
Ever Gauzy is the broadest TypeScript enterprise reference — ERP/CRM/HRM/ATS/PM on NestJS, Angular and an Nx monorepo with headless REST/GraphQL APIs — under AGPL v3 plus commercial editions, so licensing and sheer scale need evaluation before you mine it. github.com, corroborated at sinapti.ca
Start here: Huly for distributed collaborative architecture, ERPNext/Frappe for extensible business software, Ever Gauzy for a TypeScript enterprise monorepo — and Cal.com (tRPC, Prisma migrations, Playwright tests) or Plane (Django + React, webhooks, analytics) when you want a cleaner, more approachable modern SaaS codebase over maximum breadth. github.com, github.com
Decision matrix
Breadth is pattern coverage from repository evidence; approachability is a judgement of how easy the codebase is to read and reuse, which is not the same thing — the tier-1 suites are the broadest and also the heaviest.
Project
Tier
Breadth
Most valuable architecture lesson
Stack
License
Caveat
Source
Method: 40 shortlist rows (repository pages, READMEs, releases) consolidated to 10 canonical projects, corroborated against 637 broad rows across 288 hosts; research run 2026-09-20 over 1,517 unique web results before semantic filtering. Breadth counts presence of 13 named production patterns in each project’s evidence row; reference_score is semantic relevance, not GitHub popularity, and is omitted as a ranking. Duplicate forks and mirrors were cut; Medusa and Chatwoot from the brief lacked shortlist evidence rows and are noted only in prose sources.