Mário Nogueira

Building a Personal Information System: Principles and Philosophy

(LLMs were used to help organize and translate this post)

Introduction

Over the years, we accumulate an enormous amount of personal information. Identification documents, invoices, contracts, photographs, music, professional documents, certificates, notes, financial records, and countless other pieces of information become part of our personal history.

Much of this information has lasting value. Some of it is essential for everyday life; some may only become relevant years later. Some records document important events, while others preserve memories, knowledge, or work that would be difficult or impossible to recreate.

Yet this information is often scattered across devices, cloud services, applications, external drives, and physical documents. Its accessibility and preservation depend on a variety of systems and providers that we may not control.

I wanted a different approach: a system that allows me to consolidate my personal information, organize it in a comprehensible way, protect it, and preserve it for the long term.

I call it my personal information system (pIS).

This is not an attempt to build a personal cloud, reproduce every feature of a commercial productivity platform, or find a single application that does everything. It is an approach to managing personal information based on a few fundamental principles.

The most important of these is surprisingly simple: the information itself is the primary asset. Everything else exists to help me manage, access, and preserve it.

1. Start with the data

When thinking about a personal information system, it is tempting to start with the technology: which operating system to use, which applications to install, where to store the files, or which cloud provider to choose.

I prefer to start with the information.

What do I need to preserve? What might I need to access in the future? Which records are important to me, and how can I ensure that they remain available regardless of the technology I use?

My pIS covers several areas of my life:

This collection is broader than a traditional document archive. It includes records, knowledge, memories, creative work, and the information needed to manage my digital environment.

These categories also illustrate an important distinction: the value of information is not necessarily related to how frequently I access it. A document that I consult once every five years may be much more important to preserve than a file I use every day.

The objective is therefore not merely to make current work convenient. It is to ensure that information remains available when it matters.

2. Why digital?

Physical documents and photographs have their own advantages. Paper does not require an operating system, and a printed photograph can remain perfectly understandable without any special equipment.

Nevertheless, I have chosen digital storage as the foundation of my pIS.

The main reason is not simply convenience. It is the ability to manage information systematically.

Digital information can be searched, indexed, copied, backed up, reorganized, and transferred between systems. Multiple copies can be maintained in different locations without losing the original information. Files can be converted into more suitable formats as technology evolves.

A digital collection also allows different kinds of information to coexist within a common organizational structure. A property can have its contracts, invoices, photographs, equipment manuals, and related correspondence stored together, without requiring a specialized application to understand the relationship.

This does not mean that every piece of information must originate in digital form. Paper documents can be scanned, and physical photographs can be digitized. Nor does it mean that the physical originals should always be discarded. Some documents deserve to be preserved in their original form.

The point is that the digital archive becomes the central place where I organize and maintain the information.

There is a trade-off. Digital information depends on storage media, software, and ongoing maintenance. Files can become corrupted, formats can become obsolete, and systems can fail. Digital storage is not inherently permanent.

But these risks can be managed through appropriate formats, backups, verification, and migration. More importantly, digital information can be replicated and moved systematically, making it possible to design a deliberate preservation strategy.

For me, this makes digital storage a more manageable foundation for a comprehensive personal archive.

3. Sovereignty: keeping control of my information

Personal information should remain personal.

This is the principle of sovereignty that guides my choices. I want to retain control over where my information resides, how it is accessed, which applications process it, and how it can be moved elsewhere.

Cloud services and commercial platforms can be convenient, but convenience often comes with dependencies. A provider can change its prices, restrict functionality, discontinue a product, alter its terms, or shut down entirely. Data may be stored in proprietary formats or become difficult to retrieve without the original application.

I do not want the continued existence of my personal archive to depend on the goodwill or commercial success of a third party.

This does not mean that I reject all external services. They can be useful, including for storing backup copies. What matters is the distinction between using a service and depending on it as the only place where information exists or can be accessed.

My authoritative archive remains under my control. External services, where used, are subordinate to that archive rather than its owners.

Sovereignty also means having an exit strategy. If a provider disappears, I should still have my information. If I decide to change applications or infrastructure, I should be able to do so without having to reconstruct my archive from scratch.

Ideally, I can leave a service behind without losing anything important.

4. Security and privacy

Control over information is meaningful only if that information is adequately protected.

My archive contains sensitive material: identification documents, financial records, health information, family details, and other information that should not be freely accessible to third parties.

Security and privacy are therefore fundamental requirements, not optional features to add later.

Security is about protecting information against unauthorized access, accidental loss, and other threats. Privacy is about limiting unnecessary exposure and ensuring that personal information is not routinely collected, analyzed, or exploited by services whose business models depend on it.

These concerns influence both the technology I choose and the services I avoid.

I prefer software that is simple to understand and control. I am cautious about applications that depend on opaque infrastructure, extensive third-party integrations, or unnecessary online accounts. Where information is entrusted to an external service, I favor approaches that minimize what the provider can access, including end-to-end encryption where appropriate.

I also try to minimize the number of places in which sensitive information is stored. Every additional copy, integration, or service can introduce another dependency or potential point of exposure.

Of course, no system can eliminate every risk. Security involves trade-offs, and a system that is theoretically secure but difficult to operate can introduce its own problems.

My objective is to build something that is secure by design, understandable, and sustainable to maintain.

5. Longevity and portability

A personal information system should outlive the devices and applications used to create it.

Some of the information I preserve today may still be relevant decades from now. By then, the applications I currently use may no longer exist, and the operating systems, storage devices, and online services available today may have changed completely.

This leads to two closely related principles: longevity and portability.

Longevity means preserving the ability to access and understand information over time. Portability means being able to move that information between applications, systems, and providers without excessive effort.

I try to achieve both by favoring ordinary files and established, documented formats. Wherever practical, I convert documents into standard formats rather than leaving them exclusively in application-specific ones.

The goal is to avoid unnecessary dependencies between the information and the software used to manipulate it.

A PDF document, a plain-text file, a standard image format, or a lossless audio file can generally be handled by multiple independent applications. This does not guarantee perpetual compatibility, but it reduces the risk that a particular vendor or application becomes the only way to access my data.

The same reasoning applies to organization. If the archive is structured using ordinary directories and files, it remains understandable without a dedicated database or a proprietary management application.

Longevity does not mean that nothing should ever change. Formats may need to be migrated, storage devices replaced, and copies verified. Preservation is an ongoing activity.

The important point is that these changes should be under my control rather than forced upon me by the disappearance of a product.

6. Simplicity and the filesystem

The organizational structure of my pIS follows the same philosophy.

I use a directory hierarchy to separate information into broad, meaningful categories. The structure reflects the different areas of my life rather than the applications that happen to handle the files.

This is a deliberate choice. I do not want the organization of my information to depend on a particular note-taking application, document manager, or personal knowledge management platform.

The filesystem is a familiar, general-purpose abstraction. It allows me to organize information using directories and files, access it with different tools, and move it between systems.

The main categories described earlier provide the first level of organization. Within them, directories can reflect more specific subjects, assets, projects, or contexts.

For example, documents related to a particular asset can be kept together, while photographs and music remain in the media collection. Old information can be moved to the archive without losing the ability to find it later.

This approach is not intended to impose a perfect taxonomy on every piece of information. Some documents belong to several contexts, and there will always be cases where the right place is debatable. The aim is to make the structure predictable and comprehensible, not to eliminate every ambiguity.

I also value the ability to inspect the archive without specialized tools. The directory hierarchy should communicate something about the contents, and the files should remain accessible through ordinary applications.

This reflects two related influences: the Unix philosophy of small tools that do their jobs well and can work together, and the suckless philosophy of minimizing unnecessary complexity.

I prefer a collection of understandable tools over a large, integrated system whose internal behavior I cannot easily inspect or control.

Simplicity, in this context, is not an aesthetic preference alone. It is a strategy for reducing dependencies, making maintenance easier, and improving the chances that the system will remain usable over time.

7. The system matters more than any particular tool

These principles lead to a broader conclusion: a personal information system should not be defined by its current technology stack.

The operating system, applications, storage devices, and services are implementation details. They matter, but they are not the essence of the system.

The essence is the information, its organization, and the ability to preserve and access it.

I should be able to replace a laptop, change an application, adopt a different operating system, or move to another storage provider without having to rethink the entire archive. Such changes may require work, but they should not threaten the information itself.

This is also why I distinguish between the authoritative archive and the other systems that interact with it. Information can arrive from a phone, pass through another device, or be copied to external storage, but these mechanisms should not create uncertainty about which collection is the primary one.

The system should have a clear source of truth, and its other components should support that source rather than compete with it.

That distinction helps keep the architecture understandable, regardless of how the implementation evolves.

Conclusion

My pIS is an attempt to take long-term responsibility for my personal information.

It starts with the conviction that information is more valuable than the particular devices and applications used to manage it. From there, the principles follow naturally: keep control of the archive, protect privacy, minimize unnecessary dependencies, use portable formats, organize information in a comprehensible structure, and favor simple tools that can be replaced when necessary.

None of these ideas is particularly revolutionary in isolation. What matters is applying them consistently to the information accumulated throughout a lifetime.

The result I want is not the most sophisticated personal information platform. It is a system that I understand, control, and can maintain — one that continues to serve me as technologies and circumstances change.

In the end, the real measure of success is not how clever the implementation is today. It is whether, many years from now, I can still find, open, understand, and use the information that matters to me.