====== Golang Production Review Checklist ======

===== 1. Architecture Review =====

==== System Design ====

Checklist:

  * [ ] Clear separation of concerns
  * [ ] Business logic separated from transport layer
  * [ ] Business logic separated from persistence layer
  * [ ] Dependency Injection used
  * [ ] SOLID principles applied appropriately
  * [ ] High cohesion
  * [ ] Low coupling
  * [ ] Scalable design
  * [ ] Maintainable design

Recommended Structure:

<code>
cmd/
├── api/
├── worker/

internal/
├── domain/
├── service/
├── repository/
├── transport/
│   ├── http/
│   ├── grpc/
│   └── middleware/
├── infrastructure/
├── config/
└── dto/

pkg/

tests/
</code>

Review Questions:

  * [ ] Can business logic run without HTTP?
  * [ ] Can business logic run without database?
  * [ ] Can business logic be reused?

----

===== 2. Package Design Review =====

Checklist:

  * [ ] Single responsibility packages
  * [ ] No circular dependencies
  * [ ] Clear package boundaries
  * [ ] Minimal exported symbols
  * [ ] Internal package used correctly

Good:

<code>
user/
payment/
inventory/
notification/
</code>

Bad:

<code>
utils/
helpers/
common/
misc/
shared/
</code>

Review Questions:

  * [ ] Is package purpose obvious?
  * [ ] Can package be tested independently?
  * [ ] Is dependency direction correct?

----

===== 3. Interface Review =====

Checklist:

  * [ ] Small interfaces
  * [ ] Consumer-defined interfaces
  * [ ] Interface segregation respected
  * [ ] Composition preferred

Good:

<code go>
type UserRepository interface {
    GetByID(ctx context.Context, id int64) (*User, error)
}
</code>

Bad:

<code go>
type Repository interface {
    Create()
    Update()
    Delete()
    Search()
    Login()
    SendEmail()
}
</code>

Review Questions:

  * [ ] Is interface minimal?
  * [ ] Can implementation change without affecting consumers?

----

===== 4. Error Handling Review =====

Checklist:

  * [ ] No ignored errors
  * [ ] Errors wrapped properly
  * [ ] Meaningful messages
  * [ ] Context preserved

Good:

<code go>
if err != nil {
    return fmt.Errorf(
        "create order: %w",
        err,
    )
}
</code>

Bad:

<code go>
result, _ := repository.Get()
</code>

Review Questions:

  * [ ] Can root cause be identified?
  * [ ] Can logs explain failure?

----

===== 5. Context Review =====

Checklist:

  * [ ] context.Context is first parameter
  * [ ] Context propagated correctly
  * [ ] Cancellation supported
  * [ ] Timeouts configured

Good:

<code go>
func CreateOrder(
    ctx context.Context,
    req Request,
) error
</code>

Bad:

<code go>
func CreateOrder(
    req Request,
) error
</code>

Review Questions:

  * [ ] Can request be cancelled?
  * [ ] Can timeout stop execution?

----

===== 6. Concurrency Review =====

==== Goroutines ====

Checklist:

  * [ ] No goroutine leaks
  * [ ] Lifecycle managed
  * [ ] Context respected
  * [ ] Panic recovery considered

Example:

<code go>
go func() {
    select {
    case <-ctx.Done():
        return
    }
}()
</code>

==== Channels ====

Checklist:

  * [ ] Proper ownership
  * [ ] Proper closing
  * [ ] No deadlocks
  * [ ] Buffered channels justified

Review Questions:

  * [ ] Can goroutines stop safely?
  * [ ] Can system survive high load?

----

===== 7. HTTP API Review =====

Checklist:

  * [ ] Thin handlers
  * [ ] Validation performed
  * [ ] Business logic delegated
  * [ ] Consistent response format
  * [ ] Proper HTTP status codes

Good:

<code go>
func CreateOrder(
    w http.ResponseWriter,
    r *http.Request,
) {
    service.Create(...)
}
</code>

Bad:

<code go>
func CreateOrder(
    w http.ResponseWriter,
    r *http.Request,
) {
    // validation
    // business logic
    // SQL
}
</code>

Review Questions:

  * [ ] Can handlers remain simple?
  * [ ] Can business logic be tested separately?

----

===== 8. Database Review =====

==== Query Review ====

Checklist:

  * [ ] Parameterized queries
  * [ ] Proper indexes
  * [ ] Pagination used
  * [ ] No N+1 problems

Good:

<code go>
db.Query(
    "SELECT * FROM users WHERE id=?",
    id,
)
</code>

Bad:

<code go>
query := fmt.Sprintf(
    "SELECT * FROM users WHERE id=%d",
    id,
)
</code>

==== Transaction Review ====

Checklist:

  * [ ] Atomic operations protected
  * [ ] Rollbacks handled
  * [ ] Commit errors checked

Review Questions:

  * [ ] Can data become inconsistent?
  * [ ] Are failures recoverable?

----

===== 9. Security Review =====

==== Authentication ====

Checklist:

  * [ ] JWT validated
  * [ ] Password hashing secure
  * [ ] Session security reviewed

Good:

<code go>
bcrypt.GenerateFromPassword(...)
</code>

Bad:

<code go>
md5.Sum(...)
</code>

==== Authorization ====

Checklist:

  * [ ] Resource ownership checked
  * [ ] Role checks enforced
  * [ ] Least privilege applied

==== Input Security ====

Checklist:

  * [ ] Validation everywhere
  * [ ] SQL Injection prevention
  * [ ] XSS prevention
  * [ ] SSRF prevention

==== Secrets ====

Checklist:

  * [ ] No secrets in code
  * [ ] Environment variables used
  * [ ] Secret manager considered

Review Questions:

  * [ ] Can attacker access sensitive data?
  * [ ] Are permissions minimized?

----

===== 10. Logging Review =====

Checklist:

  * [ ] Structured logging
  * [ ] Correlation IDs
  * [ ] Error logging
  * [ ] Business event logging

Good:

<code go>
logger.Info(
    "order_created",
    "order_id",
    orderID,
)
</code>

Bad:

<code go>
fmt.Println(orderID)
</code>

Review Questions:

  * [ ] Can production issues be diagnosed?
  * [ ] Can request flow be traced?

----

===== 11. Configuration Review =====

Checklist:

  * [ ] Configuration centralized
  * [ ] Environment-specific configs
  * [ ] Startup validation
  * [ ] Sensible defaults

Example:

<code>
APP_PORT
DB_HOST
DB_NAME
REDIS_HOST
</code>

Review Questions:

  * [ ] Can configuration be changed safely?
  * [ ] Can secrets be rotated?

----

===== 12. Performance Review =====

Checklist:

  * [ ] Memory allocations optimized
  * [ ] Database queries optimized
  * [ ] Connection pools configured
  * [ ] Caching strategy exists

==== Profiling ====

Checklist:

  * [ ] pprof enabled
  * [ ] CPU profile reviewed
  * [ ] Memory profile reviewed

Commands:

<code bash>
go tool pprof
</code>

Review Questions:

  * [ ] Can application handle 10x traffic?
  * [ ] Are bottlenecks identified?

----

===== 13. Testing Review =====

==== Unit Tests ====

Checklist:

  * [ ] Service tests
  * [ ] Domain tests
  * [ ] Business rule tests

==== Integration Tests ====

Checklist:

  * [ ] Database tests
  * [ ] API tests
  * [ ] Queue tests

==== Coverage ====

Targets:

  * [ ] Critical logic > 90%
  * [ ] Overall > 70%

Commands:

<code bash>
go test ./...
go test -cover ./...
</code>

Review Questions:

  * [ ] Can critical bugs be caught?
  * [ ] Is regression risk minimized?

----

===== 14. Queue & Worker Review =====

Checklist:

  * [ ] Retry policy defined
  * [ ] Dead letter queue configured
  * [ ] Idempotent processing
  * [ ] Backoff strategy

Review Questions:

  * [ ] Can jobs be retried safely?
  * [ ] Can duplicate processing occur?

----

===== 15. Observability Review =====

==== Metrics ====

Checklist:

  * [ ] Request count
  * [ ] Error rate
  * [ ] Latency
  * [ ] Business metrics

==== Tracing ====

Checklist:

  * [ ] Distributed tracing
  * [ ] Request tracing
  * [ ] Context propagation

Review Questions:

  * [ ] Can incidents be diagnosed quickly?
  * [ ] Can slow requests be identified?

----

===== 16. Cloud Native Review =====

Checklist:

  * [ ] Stateless design
  * [ ] Health endpoint
  * [ ] Readiness endpoint
  * [ ] Metrics endpoint
  * [ ] Graceful shutdown

Endpoints:

<code>
/health
/ready
/metrics
</code>

Review Questions:

  * [ ] Can service run in Kubernetes?
  * [ ] Can service scale horizontally?

----

===== 17. Graceful Shutdown Review =====

Checklist:

  * [ ] SIGTERM handled
  * [ ] HTTP server shutdown
  * [ ] Worker shutdown
  * [ ] DB connections closed

Example:

<code go>
server.Shutdown(ctx)
</code>

Review Questions:

  * [ ] Can deployments happen safely?
  * [ ] Can requests finish gracefully?

----

===== 18. CI/CD Review =====

Checklist:

  * [ ] gofmt
  * [ ] golangci-lint
  * [ ] Unit tests
  * [ ] Security scans
  * [ ] Automated deployments

Pipeline:

<code>
Git Push
 ↓
gofmt
 ↓
golangci-lint
 ↓
Unit Tests
 ↓
Build
 ↓
Docker Build
 ↓
Deploy
</code>

Review Questions:

  * [ ] Can bad code reach production?
  * [ ] Can rollback happen safely?

----

===== 19. Production Readiness =====

==== Reliability ====

Checklist:

  * [ ] Retry strategy
  * [ ] Timeout strategy
  * [ ] Circuit breaker considered
  * [ ] Rate limiting implemented

==== Scalability ====

Checklist:

  * [ ] Horizontal scaling
  * [ ] Shared cache
  * [ ] Shared storage
  * [ ] Queue scaling

==== Disaster Recovery ====

Checklist:

  * [ ] Backup strategy
  * [ ] Restore procedures
  * [ ] Runbooks documented

Review Questions:

  * [ ] Can service survive failures?
  * [ ] Can service recover quickly?

----

===== 20. Senior Golang Final Review =====

  - [ ] Is code simple?
  - [ ] Is business logic framework-independent?
  - [ ] Are interfaces small?
  - [ ] Is context propagated correctly?
  - [ ] Are errors handled properly?
  - [ ] Are goroutines leak-free?
  - [ ] Is application observable?
  - [ ] Can service scale horizontally?
  - [ ] Can another engineer maintain it in 6 months?
  - [ ] Will this wake me up at 3 AM?

If all answers are YES, the Golang application is Production Ready.

----

===== Golang Maturity Score =====

^ Category ^ Target ^
| Architecture | 9/10 |
| Package Design | 9/10 |
| Concurrency | 9/10 |
| Security | 9/10 |
| Performance | 9/10 |
| Testing | 8/10+ |
| Scalability | 9/10 |
| Observability | 8/10+ |
| Maintainability | 9/10 |

Overall Production Grade Target: >= 85%