What is the distributed monolith and other microservices anti-patterns?

Question

Accepted Answer

The worst microservices outcome is a **"distributed monolith"**: services that are physically separate but so tightly coupled they must be deployed together — you get all the cost of distribution and none of the independence.

## Signs of a distributed monolith

```text
✗ Changing one service forces redeploying several others
✗ Services share a database / shared schema
✗ A single request fans out through many synchronous hops
✗ Releases must be coordinated across teams
→ you pay network + ops cost but lost independent deployability
```

## Other common anti-patterns

| Anti-pattern | Problem |
|---|---|
| Shared database | Re-couples services; no independent schema change |
| Chatty services | Many sync calls per request → latency, fragility |
| Nano-services | Too fine-grained; overhead dwarfs the logic |
| No API versioning | One change breaks every consumer |
| Synchronous chains | Latency and failure multiply along A→B→C→D |
| God service | One service everyone depends on (a new monolith) |

## The root cause

Usually **wrong boundaries**. Services split by technical layer or entity (not business capability) end up chatty and co-dependent.

```text
bad:  User-svc, Product-svc, Cart-svc all called for one checkout
good: Checkout owns the capability end to end
```

## Why it matters

A distributed monolith is strictly worse than a real monolith — slower, harder to debug, more to operate, yet still impossible to deploy independently.

Most anti-patterns trace back to boundaries and a shared database, so getting bounded contexts and data ownership right is what separates microservices that help from ones that hurt.

Anti-pattern	Problem
Shared database	Re-couples services; no independent schema change
Chatty services	Many sync calls per request → latency, fragility
Nano-services	Too fine-grained; overhead dwarfs the logic
No API versioning	One change breaks every consumer
Synchronous chains	Latency and failure multiply along A→B→C→D
God service	One service everyone depends on (a new monolith)