MongoDB vs DynamoDB for Solo Developers

Quick Comparison

MongoDB Overview

MongoDB stores data as flexible JSON-like documents. You do not need a schema upfront, queries are intuitive if you know JavaScript, and the managed Atlas platform handles infrastructure. The free tier gives you 512 MB on a shared cluster, enough for prototyping and small applications.

What makes MongoDB appealing for solo developers is familiarity. Documents look like JavaScript objects. The query API is straightforward. Mongoose adds schema validation and middleware for Node.js projects. The community is huge, tutorials are everywhere, and you can go from zero to a working database in minutes.

MongoDB is also portable. You can run it locally, self-host it on a VPS, or use Atlas in the cloud. Your data is in a standard format, and you are not locked into any specific cloud provider.

DynamoDB Overview

DynamoDB is Amazon's fully managed NoSQL database. It stores key-value pairs and documents, delivering single-digit millisecond performance at virtually any scale. AWS built it to handle their own shopping cart system, and it runs some of the highest-traffic services in the world.

The fully managed aspect is real. No servers to provision, no patches, no backups to configure. AWS handles everything. The free tier provides 25 GB of storage and enough capacity for about 200 million read/write requests per month, which is generous.

But DynamoDB requires a fundamentally different approach to data modeling. You must know your access patterns before you design your tables. You cannot run arbitrary queries. You design partition keys and sort keys based on how your application reads and writes data. Getting this wrong means poor performance or expensive table scans.

Key Differences

Data modeling complexity. MongoDB is flexible. You store documents, create indexes as needed, and query in multiple ways. DynamoDB requires you to design your schema around your access patterns. Single-table design patterns, composite sort keys, and Global Secondary Indexes are all concepts you need to master. For a solo developer iterating on a product, MongoDB's flexibility lets you change direction without redesigning your database.

Query flexibility. MongoDB lets you query any field, create compound indexes, run aggregation pipelines, and perform ad-hoc queries for debugging or reporting. DynamoDB queries require a partition key. Everything else requires a scan (expensive) or a Global Secondary Index (costs money and must be planned ahead). Need a report you did not anticipate? MongoDB handles it. DynamoDB makes you pay.

Vendor lock-in. MongoDB is open source. You can run it on any cloud, self-host it, or use Atlas. DynamoDB is AWS-only. Building on DynamoDB means committing to AWS for your data layer. Migrating away requires rewriting your entire data access code. For a solo developer, MongoDB's portability is a significant advantage.

Pricing models. MongoDB Atlas free tier is limited but functional (512 MB). DynamoDB's free tier is more generous (25 GB, 200M requests). Beyond free tiers, MongoDB Atlas starts at $57/month for dedicated instances. DynamoDB uses pay-per-request or provisioned capacity pricing, which can be cheaper for low-traffic apps but expensive for high-throughput workloads. DynamoDB pricing is notoriously hard to predict.

Operational overhead. DynamoDB wins here. It is truly zero-ops. No capacity planning for the infrastructure, no server management, no version upgrades. MongoDB Atlas is managed but still requires you to choose cluster sizes, handle scaling decisions, and manage connection limits. For a solo developer who wants to never think about database operations, DynamoDB's managed nature is appealing.

Local development. MongoDB runs locally with a simple install or Docker container. DynamoDB requires either DynamoDB Local (a Java-based emulator) or connection to AWS. The local development experience with MongoDB is better and more reliable.

When to Choose MongoDB

• You are iterating on your data model and need flexibility
• You want to avoid vendor lock-in to AWS
• Ad-hoc queries and reporting are part of your workflow
• Local development experience matters to you
• You prefer a familiar, intuitive query language

When to Choose DynamoDB

• You are already heavily invested in AWS
• Your access patterns are well-defined and stable
• You need truly zero-ops database management
• Single-digit millisecond latency at any scale is required
• The AWS free tier's generous allowances fit your budget

The Verdict

MongoDB is the better choice for most solo developers. The 7/10 vs 5/10 rating comes down to flexibility and accessibility. MongoDB lets you query freely, iterate on your schema, develop locally without emulators, and avoid vendor lock-in. DynamoDB is powerful but demands that you know your access patterns upfront, locks you into AWS, and punishes you financially for queries you did not plan for.

DynamoDB excels when you are building within AWS, your data model is stable, and you want zero operational burden. But for the typical solo developer building a SaaS, marketplace, or content platform where requirements change weekly, MongoDB's flexibility is far more practical. And if you want the best of both worlds (managed, flexible, and powerful), consider PostgreSQL through Supabase or Neon instead of either NoSQL option.