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. The M0 free tier gives you 512 MB of storage on a shared cluster, 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, public domain, with no hosting costs beyond your existing server. The MongoDB Atlas M0 free tier is limited to 512 MB. Beyond that you move to Flex (around $30 per month ceiling) or the M10 dedicated tier at $56.94 per month, which is also the first tier that includes backups. 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

By the Numbers (2026)

The specs below were pulled directly from vendor pricing pages, official release logs, the npm registry, and the GitHub API on 2026-05-29. Sources are listed at the end.

Versions. MongoDB's current stable server line is 8.3, with the most recent Community patch being 8.2.9 shipped 2026-05-12. The official Node.js driver on npm sits at 7.2.0. SQLite's latest release is 3.53.1, dated 2026-05-05, a patch that fixed a WAL-reset corruption bug from 3.53.0.

Pricing and limits. MongoDB Atlas M0 is free forever with 512 MB of storage on a shared cluster. The Flex tier runs at $0.011 per hour and caps around $30 per month with 5 GB of storage. The smallest dedicated tier, M10, starts at $56.94 per month for 2 GB RAM, 2 vCPUs, and 10 to 128 GB of storage, and it is the first tier that includes backups. SQLite has no pricing page because it is public domain. Your only cost is the disk it sits on, which on a server you already run is effectively zero.

Adoption. The MongoDB driver pulls roughly 11.3 million npm downloads per week (period 2026-05-21 to 2026-05-27). On the SQLite side, the two main Node bindings together draw about 8.8 million weekly downloads, 6.5 million for better-sqlite3 and 2.3 million for sqlite3, over the same window. On GitHub, the mongodb/mongo server repository carries 28,334 stars; the official SQLite source mirror carries 9,711, which undersells reach because SQLite is famously not developed on GitHub and ships bundled inside operating systems rather than installed from a repo.

Scale of deployment. SQLite's own project page claims it is the most widely deployed database engine in the world, estimating over one trillion SQLite databases in active use, largely because every smartphone carries hundreds of SQLite files. That is the practical backdrop to the "most deployed database" line above.

Real Cost at Solo-Dev Scale

Money is usually the deciding factor for a solo project, so here is a worked example using the real rates above.

Assume a typical side project that has outgrown a free tier: a small web app with about 2 GB of data and steady but not heavy traffic, running on a $6 per month VPS you already pay for.

SQLite on that setup. The database is a file on the same VPS. Incremental database cost is $0 per month. Your total stays at the $6 you were already spending on the box.

MongoDB on that setup. The 2 GB of data exceeds the 512 MB M0 free tier, so you move up. The Flex tier covers 5 GB and bills at $0.011 per hour. Running continuously, that is 0.011 times roughly 730 hours, about $8 per month, capped at $30 if usage spikes. So you are looking at roughly $8 per month on top of the $6 VPS, call it $14 per month all in, and that is before you need the backups and replica sets that only start at the M10 dedicated tier ($56.94 per month).

Over a year, SQLite adds $0 while a managed MongoDB Flex cluster adds roughly $96, climbing toward $683 per year the moment you need a real dedicated tier with backups. For a profitable product those numbers are noise. For an unproven side project, the gap between free and "$57 a month for backups" is exactly the kind of fixed cost that kills momentum.

Assumptions, stated plainly: continuous Flex billing at the published $0.011 per hour, roughly 730 hours per month, and the VPS treated as a sunk cost shared with the rest of the app. If your data fits under 512 MB, MongoDB Atlas M0 is genuinely free and this section does not apply, but then SQLite is still free too and needs no network round trip.

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.

Sources

All figures checked on 2026-05-29.

• MongoDB Atlas pricing (M0 free 512 MB, Flex $0.011/hr up to $30/mo, M10 from $56.94/mo): https://www.mongodb.com/pricing
• MongoDB server release notes (8.3 current stable; 8.2 community line): https://www.mongodb.com/docs/manual/release-notes/
• MongoDB 8.2 release notes (8.2.9 patch dated 2026-05-12): https://www.mongodb.com/docs/manual/release-notes/8.2/
• MongoDB Node.js driver version 7.2.0: https://registry.npmjs.org/mongodb/latest
• MongoDB driver npm weekly downloads (11,312,820 for 2026-05-21 to 2026-05-27): https://api.npmjs.org/downloads/point/last-week/mongodb
• MongoDB server GitHub stars (28,334): https://api.github.com/repos/mongodb/mongo
• SQLite release 3.53.1 dated 2026-05-05: https://sqlite.org/releaselog/3_53_1.html
• SQLite release history: https://sqlite.org/changes.html
• SQLite most-deployed claim (over one trillion databases in active use): https://sqlite.org/mostdeployed.html
• better-sqlite3 version 12.10.0: https://registry.npmjs.org/better-sqlite3/latest
• better-sqlite3 npm weekly downloads (6,504,448 for 2026-05-21 to 2026-05-27): https://api.npmjs.org/downloads/point/last-week/better-sqlite3
• sqlite3 npm weekly downloads (2,286,246 for 2026-05-21 to 2026-05-27): https://api.npmjs.org/downloads/point/last-week/sqlite3
• SQLite source mirror GitHub stars (9,711): https://api.github.com/repos/sqlite/sqlite