These aren't sanitized success stories. These are real developers who lived through ORM migrations and came out the other side.
The E-commerce Disaster That Worked Out
My buddy Mike was running an e-commerce backend that was hemorrhaging money on AWS Lambda. Cold starts were 6+ seconds, Accelerate was costing $300/month, and customers were bouncing because checkout took forever.
Week 1: Mike starts converting to Drizzle. Schema translation goes surprisingly well - turns out Drizzle schemas look a lot like Prisma if you squint.
Week 2: Query rewriting is hell. Prisma's magic nested creates don't exist anymore. Mike has to learn transactions, figure out foreign keys manually, and write 3x more code for relationship handling. Spent 6 hours getting foreign key constraint violation errors before realizing he forgot to enable foreign key checks in development.
Week 3: Integration testing catches a bug where order totals weren't calculating correctly when customers had both discount codes AND store credit. The nested transaction logic in Prisma was silently failing - no errors, just wrong math. Would have been a "hey why did we charge this customer $0 for a $500 order" production nightmare.
The result: Cold starts dropped to 300ms, bundle size went from the old 22MB Prisma to 180KB with Drizzle, eliminated Accelerate entirely. Mike's running the same traffic on 1/4 the infrastructure cost.
The catch: Mike's team had to learn SQL properly. Two developers quit because they "didn't sign up to write database queries." The ones who stayed are much better engineers now.
The TypeORM Disaster
Sarah's startup decided to migrate from Prisma to TypeORM because it was "more enterprise." Big fucking mistake.
Week 1: Decorators everywhere. @Entity, @Column, @OneToMany - the codebase looked like Java threw up on it.
Week 2: Relationship loading breaks everything. Lazy vs eager loading, N+1 queries, circular dependencies. Sarah's spending entire days debugging why @ManyToOne(() => User, user => user.posts) worked in development but threw EntityNotFoundError: Cannot resolve target entity "User" in production. Same fucking code, different environment.
Week 4: Production performance is worse than Prisma. TypeORM is doing weird queries, the query logging is cryptic, and nobody on the team understands SQL well enough to optimize.
Week 6: They give up and rollback. Six weeks of development time lost, team demoralized, investors asking why features are behind schedule.
The lesson: TypeORM requires database expertise they didn't have. Great ORM if you know what you're doing, suicide mission if you don't.
The Nuclear Option Success
Alex got so fed up with ORMs he said "fuck it" and went straight to raw SQL with postgres.js. Smartest thing he ever did.
Migration time: took me about 8 days over 2 weeks while still shipping features.
The approach: Threw away every abstraction, wrote SQL by hand, typed everything manually.
What he gained:
- Bundle size: 25MB → 60KB
- Cold starts: 4 seconds → 80ms
- Perfect understanding of every database operation
- No more
prisma generate bullshit
- Zero vendor lock-in
What he lost:
- Relationship helpers (wrote his own)
- Visual schema tools (uses TablePlus now)
- Type generation (maintains interfaces manually)
Six months later Alex says it's the best engineering decision he ever made. His app is blazing fast, deploys are instant, and he actually understands his database.
The Hybrid Hack
DevOps team at a fintech couldn't migrate everything at once - too much legacy code, too many compliance requirements. So they got creative.
The problem: Complex financial reports were killing Prisma. They were writing $queryRaw everywhere, which defeats the point of using an ORM.
The solution: Keep Prisma for simple CRUD, introduce Kysely for analytics and reporting.
// Complex shit in Kysely
const report = await analyticsDb
.select([
sql`date_trunc('month', t.created_at)`.as('month'),
sql`sum(amount)`.as('revenue')
])
.from('transactions as t')
.where('status', '=', 'completed')
.groupBy(sql`date_trunc('month', t.created_at)`);
// Simple stuff still in Prisma
const user = await prisma.user.create({ data: userData });
Result: Report queries run 5x faster, CRUD velocity unchanged, team learning SQL gradually. They're migrating the rest over 18 months as they touch each domain.
Why it works: Different tools for different jobs. Don't let ORM purists tell you otherwise.
The Bundle Size Fix That Came Too Late
Jenny upgraded to Prisma's improved client after they finally fixed the bundle size issues. She got the improvements they promised, but it was too little too late.
Week 1: Bundle size dropped significantly with the new rust-free client. Cold starts improved from 5 seconds to under 1 second. Actually usable now.
Week 2: New bugs appear. The TypeScript client has different behavior in edge cases. Tests that worked with the old client start failing randomly with Error: Invalid date value. Specifically, our date handling broke - the new client serializes DateTime fields differently, and suddenly half our API responses had malformed timestamps.
Week 3: Jenny realizes she's still debugging Prisma issues instead of building features. The "new and improved" client is still the same architectural disaster underneath.
The decision: Fuck it, migrating to Drizzle anyway. If she's going to spend weeks debugging, might as well fix the root cause.
Final result: 6 weeks total to get completely off Prisma. Bundle size dropped to 180KB, cold starts under 400ms, zero ongoing costs. The bundle size fix was too little, too late.
The Agency Rollback
Development agency tried MikroORM because they read some Domain-Driven Design article and wanted "better architecture."
Week 1: Entire team spent learning Unit of Work patterns instead of migrating code. Client deadline approaching.
Week 2: Basic CRUD works but relationship loading is fucked. Entity manager lifecycle, identity maps, change tracking - it's like learning a new programming paradigm.
Week 3: Realization hits: MikroORM isn't just an ORM replacement, it requires redesigning the entire application architecture.
Outcome: Emergency rollback to Prisma, client project delivered on time, team swears off "enterprise" solutions.
The lesson: MikroORM is excellent but it's not a drop-in replacement. It's an architectural decision that affects your entire application.
What I Learned From All This
Successful migrations have common patterns:
- Team knows SQL or learns it quickly
- Schema translation first, query optimization second
- Comprehensive testing before cutover
- Gradual rollout with rollback plan
Failed migrations also have patterns:
- Team underestimates learning curve
- All-or-nothing approach with no rollback
- Migration during high-pressure periods
- Choosing tools that don't fit team expertise
Bottom line: The ORM isn't the problem, your team's database knowledge is. Fix that first.
