--- title: How Domain Boundary Violations Slowly Destroy Your Codebase description: Domain boundary violations occur when services directly manipulate or depend on each other's internals, creating circular dependencies, fragile dependency... canonical: https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: How Domain Boundary Violations Slowly Destroy Your Codebase | daily.dev og:description: Domain boundary violations occur when services directly manipulate or depend on each other's internals, creating circular dependencies, fragile dependency... og:url: https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz og:image: https://api.daily.dev/og/posts/eNAy5Y3Sz.png og:image:alt: How Domain Boundary Violations Slowly Destroy Your Codebase og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # How Domain Boundary Violations Slowly Destroy Your Codebase **[Towards Dev](https://daily.dev/sources/towardsdev)** · 6 min read · 16 upvotes · 0 comments ## Summary Domain boundary violations occur when services directly manipulate or depend on each other's internals, creating circular dependencies, fragile dependency graphs, and untestable code. Using NestJS as a concrete example, the post walks through real symptoms like widespread `forwardRef()` usage, duplicate provider declarations, and fragmented orchestration logic. The prescribed fix is introducing an orchestration layer (e.g., `LeadLifecycleService`) that owns all cross-domain coordination, while individual domain services remain focused on their own invariants and CRUD operations — resulting in an acyclic, testable, and maintainable architecture. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What does forwardRef in NestJS actually indicate about my architecture? Frequent use of forwardRef signals that domain boundaries are violated, not just a dependency injection quirk. It delays dependency resolution to let circular graphs work, which is harmless only in rare cases like event-driven, plugin, or observer patterns, but in most line-of-business backends its widespread presence means services are reaching sideways into each other's logic instead of staying isolated. _Developers untangling circular NestJS dependencies can find similar architecture deep-dives on daily.dev._ ### How do I fix circular dependencies between domain services without using forwardRef everywhere? Introduce an orchestration or lifecycle layer, such as a LeadLifecycleService, that owns all cross-domain coordination and depends on the domain services, while those domain services never depend back on the orchestrator. Domain services stay focused on CRUD and invariants, dependencies flow down the stack rather than sideways, and forwardRef and duplicate provider declarations can be removed entirely. _Teams designing cleaner service boundaries can track architecture patterns like this one on daily.dev._ ## Similar posts on daily.dev - [NestJS Module Boundaries That Survive Growth](https://daily.dev/posts/nestjs-module-boundaries-that-survive-growth-bzh5p5uw6) · Medium · 2 upvotes · 2 comments - [Why are we talking about architecture again?](https://daily.dev/posts/why-are-we-talking-about-architecture-again--qeiyintcw) · ITNEXT · 19 upvotes · 3 comments - [The Vertical Codebase](https://daily.dev/posts/the-vertical-codebase-kioev85i9) · TkDodo · 73 upvotes · 5 comments - [Enforce TypeScript Architecture Boundaries via AST Import Graphs](https://daily.dev/posts/enforce-typescript-architecture-boundaries-via-ast-import-graphs-3k2xiuqvu) · SitePoint · 1 upvotes · 0 comments --- Tags: [#architecture](https://daily.dev/tags/architecture), [#dependency-injection](https://daily.dev/tags/dependency-injection), [#nestjs](https://daily.dev/tags/nestjs), [#domain-driven-design](https://daily.dev/tags/domain-driven-design) [View this post on daily.dev](https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"How Domain Boundary Violations Slowly Destroy Your Codebase","url":"https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz"},"datePublished":"2026-07-21T21:13:46.011Z","dateModified":"2026-09-14T07:38:26.377Z","description":"Domain boundary violations occur when services directly manipulate or depend on each other's internals, creating circular dependencies, fragile dependency...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/0533b4538c0e85c5decbae2a3a08ae05?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/0533b4538c0e85c5decbae2a3a08ae05?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Towards Dev","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Towards Dev","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/2c710db2750a4a70835862534cb7c9d4","url":"https://daily.dev/sources/towardsdev"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":16},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"architecture,dependency-injection,nestjs,domain-driven-design","timeRequired":"PT6M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Towards Dev","item":"https://daily.dev/sources/towardsdev"},{"@type":"ListItem","position":3,"name":"How Domain Boundary Violations Slowly Destroy Your Codebase"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/how-domain-boundary-violations-slowly-destroy-your-codebase-enay5y3sz#faq","mainEntity":[{"@type":"Question","name":"What does forwardRef in NestJS actually indicate about my architecture?","acceptedAnswer":{"@type":"Answer","text":"Frequent use of forwardRef signals that domain boundaries are violated, not just a dependency injection quirk. It delays dependency resolution to let circular graphs work, which is harmless only in rare cases like event-driven, plugin, or observer patterns, but in most line-of-business backends its widespread presence means services are reaching sideways into each other's logic instead of staying isolated. Developers untangling circular NestJS dependencies can find similar architecture deep-dives on daily.dev."}},{"@type":"Question","name":"How do I fix circular dependencies between domain services without using forwardRef everywhere?","acceptedAnswer":{"@type":"Answer","text":"Introduce an orchestration or lifecycle layer, such as a LeadLifecycleService, that owns all cross-domain coordination and depends on the domain services, while those domain services never depend back on the orchestrator. Domain services stay focused on CRUD and invariants, dependencies flow down the stack rather than sideways, and forwardRef and duplicate provider declarations can be removed entirely. Teams designing cleaner service boundaries can track architecture patterns like this one on daily.dev."}}]} ```