The Build vs. Buy Dilemma for Reference Data Management

Every developer has been there. You're building a new feature, and you need a dropdown list of countries. "Easy enough," you think, quickly creating a static array or a simple JSON file. It works. For a while.

But then another service needs that same list. A third needs a list of world currencies. A fourth needs industry classification codes. Soon, these simple lists are scattered across your codebase, slowly drifting out of sync. Updating them becomes a manual, error-prone chore. You've stumbled into one of the most common, yet deceptively complex, challenges in software development: managing reference data.

Reference data is the foundational, slow-changing information that provides context to everything else—country codes (ISO 3166), currencies (ISO 4217), languages (ISO 639), and even your own internal lists of product categories or store locations.

This leads every growing engineering team to a critical crossroads: Do we build our own internal service to manage this data, or do we buy a managed solution? Let's break down the true costs and benefits of each path.

The "Build" Path: The Allure of a Custom Microservice

On the surface, building a reference data microservice seems straightforward. "It's just an API that serves a few lists," you might argue. "We can build it in a weekend."

This initial simplicity is deceptive. A truly robust and reliable internal solution involves far more than a single endpoint.

The Real Development Requirements

1. Initial Scaffolding: You need more than just code. You need a data store (like Postgres or a document DB), a well-designed REST or GraphQL API, robust authentication, and clear documentation so other teams can actually use it.
2. Data Sourcing and Management: Where does your data come from? For standard datasets like ISO codes, you'll need to find a reliable source, write scripts to parse and clean the data, and create a process to periodically check for and ingest updates. (Did you know South Sudan changed its currency code in 2021?)
3. Essential Features: A simple data dump isn't enough. Users will quickly demand more. Can they query the data (e.g., "find all currencies used in Europe")? Is the data versioned? Can they fetch a list of countries and their corresponding currencies in a single call? Each new feature adds to the development backlog.
4. Handling Custom Data: What about your company's proprietary reference data? Soon, the marketing team will want to manage a list of campaign codes, and the product team will need to update product categories. Your "simple" service now needs a user interface for data uploads, validation rules, and access controls.

The Hidden Cost: Total Cost of Ownership (TCO)

The most significant cost isn't the initial build; it's the ongoing maintenance. This internal service is now a piece of critical infrastructure. It requires:

• Constant Monitoring: Is the API up? Is it performant?
• Security Patching: The service, its database, and all its dependencies need to be kept secure.
• On-Call Rotation: When the service goes down, it can block deployments and even break production applications. Someone needs to be on call to fix it.
• Developer Time: Your engineers are now spending cycles maintaining this internal tool instead of building the core product features that drive revenue.

What began as a "quick project" has morphed into an internal product with a surprisingly high total cost of ownership.

The "Buy" Path: A Managed API for Reference Data

The alternative is to treat reference data management as a solved problem and leverage a specialized service. This is where a solution like reference.do comes in. It's designed from the ground up to be a single source of truth for all your reference data, accessed through one simple, reliable API.

Immediate and Long-Term Benefits

Buying a managed solution flips the equation. Instead of investing time in building infrastructure, you can start integrating immediately.

1. Zero Infrastructure, Instant Access

Stop worrying about servers, databases, and uptime. You can get a rich set of standardized reference data with a simple API call.

import { Do } from '@do-inc/sdk';

const an = new Do(process.env.DO_API_KEY);

// Get a list of all ISO 4217 currencies
const currencies = await an.reference.get('iso-4217');

console.log(currencies);
/*
=> [
     { "code": "USD", "name": "United States Dollar", "symbol": "$" },
     { "code": "EUR", "name": "Euro", "symbol": "€" },
     { "code": "JPY", "name": "Japanese Yen", "symbol": "¥" },
     ...
   ]
*/

2. Guaranteed Data Quality

A managed provider's entire business is data quality. They handle the sourcing, cleaning, validation, and continuous updating of standard public datasets, so you don't have to. You can trust that the ISO codes and other master data are always current.

3. Unify Standard and Custom Data

This is where the real power lies. A robust platform like reference.do doesn't just serve public data. It allows you to upload, manage, version, and query your own proprietary datasets right alongside the standard ones—all through the same unified API. Your internal product categories live in the same place as ISO country codes, creating a true single source of truth.

4. Radically Lower TCO

With a predictable subscription, you eliminate the hidden costs of maintenance, hosting, and operational overhead. Your developers are freed from infrastructure management and can focus 100% of their effort on your core application logic.

The Verdict: Focus on What Makes You Unique

While the instinct to build can be strong, reference data management is a classic example of a problem that is complex to solve well but easy to offload. Building your own solution means you're taking on the role of a data provider—a role that distracts from your primary business goals.

By choosing a managed API, you're not just buying data; you're buying back your team's most valuable resource: time. You're ensuring consistency, reducing technical debt, and establishing a single source of truth that empowers every application you build.

Ready to stop managing static lists and start building faster? Explore how reference.do can become your single source of truth for reference data.