MongoDB vs SQLite for Solo Developers

Quick Comparison

MongoDB Overview

MongoDB stores data as flexible JSON-like documents instead of rows in tables. This means you can throw a JavaScript object at it and it saves without needing a predefined schema. For rapid prototyping, this flexibility is appealing. You do not need to write migrations every time your data shape changes.

MongoDB Atlas provides a free tier that is genuinely useful. 512 MB of storage, shared cluster, and enough capacity for a small application. The managed service handles backups, updates, and monitoring. For a solo developer, not managing database infrastructure is a big plus.

The trade-off is that MongoDB's flexibility can become a liability. Without schema enforcement, data inconsistencies creep in over time. Queries that would be simple JOINs in SQL require aggregation pipelines that are verbose and harder to debug. As your application grows, you might find yourself wishing for the structure that a relational database provides.

SQLite Overview

SQLite is the most deployed database in the world, and it is not even close. It runs on every smartphone, inside every web browser, and in countless embedded systems. It is a single file on disk. No server process, no configuration, no network connections. You include it in your application and it works.

For solo developers, SQLite is incredibly powerful. Zero configuration means you start building immediately. The database is a single file you can copy, back up, or version control. Read performance is excellent. For applications with low to medium write concurrency, SQLite handles the workload without any issues.

The renaissance of SQLite for web applications is real. Tools like Turso, Litestream, and LiteFS have made SQLite viable for production web apps. Frameworks like Rails now default to SQLite. The simplicity-to-capability ratio is unmatched.

Key Differences

Schema flexibility vs structure. MongoDB lets you store any document shape in any collection. SQLite requires a defined schema with tables and columns. For solo developers, SQLite's schema enforcement is actually a feature, not a limitation. It catches data inconsistencies at the database level instead of letting them silently accumulate. MongoDB's flexibility is useful for prototyping, but structured data belongs in a structured database.

Deployment complexity. SQLite requires nothing. It is a library linked into your application. Your database is a file on disk. MongoDB requires either a server running mongod or a managed Atlas instance. For a solo developer deploying a side project, SQLite's zero-dependency deployment is hard to beat.

Querying power. SQLite supports full SQL, including JOINs, subqueries, CTEs, window functions, and full-text search (FTS5). MongoDB uses its own query language and aggregation pipelines. For simple lookups, both work fine. For complex queries involving multiple collections (tables), SQL is more expressive and easier to write than MongoDB's aggregation framework.

Concurrency model. MongoDB handles concurrent writes well across multiple connections. SQLite allows only one writer at a time (though WAL mode improves this significantly). For a solo developer's application with moderate traffic, SQLite's concurrency is perfectly adequate. If you are building a high-concurrency real-time application with thousands of simultaneous writes, MongoDB handles that better.

Cost comparison. SQLite is completely free. No hosting costs beyond your existing server. MongoDB Atlas free tier is limited to 512 MB. Beyond that, you are paying for hosting. For budget-conscious solo developers, SQLite's zero cost is a meaningful advantage.

Portability. SQLite databases are single files. You can copy them, email them, put them in git. Testing with production data means copying one file. MongoDB data export and import involves mongodump and mongorestore, which works but is more involved.

When to Choose MongoDB

• Your data is genuinely document-oriented (nested, variable structures)
• You need horizontal scaling across multiple servers
• Your application has high write concurrency
• You are building a real-time application with frequent schema changes
• You want a managed cloud database with a free tier

When to Choose SQLite

• You want the simplest possible database setup
• Your application has low to medium traffic
• You value the ability to deploy as a single file
• You want full SQL querying without any compromise
• Budget is a concern and you want zero hosting costs

The Verdict

SQLite is the better choice for most solo developers. The 9/10 vs 7/10 rating reflects the practical reality: SQLite is simpler, free, requires no management, deploys as a file, and supports full SQL. MongoDB's document flexibility sounds appealing in theory, but most solo developer applications have relational data that fits naturally into tables. The schema-less approach that speeds up prototyping creates data quality problems later.

Start with SQLite. If your application genuinely outgrows it (high concurrent writes, need for horizontal scaling), you will know. At that point, consider PostgreSQL before MongoDB. For most solo projects, SQLite is all you need.