Embedded firmware development isn’t the same animal as web and mobile application development. We can’t always treat it the same. Discontinuous delivery places an emphasis on the need for proper configuration management (CM) for firmware that starts with the build and continues all the way through delivery.

CM serves as the anchor that prevents chaos from derailing the firmware development, test, and delivery workflow. Embedded firmware must be meticulously managed from conception to deployment in order to know who has what, who gets what, what version supports which hardware, and to recreate previous releases for bug fixing and forking.

Without robust CM practices, the complexity of tracking code changes, build configurations, and deployment statuses can quickly spiral out of control, leading to costly mistakes and system failures.

Unfortunately, it’s easy to miss some crucial information.

This article will guide you through the essentials of configuration management in embedded firmware development. We’ll explore what needs to be tracked, how to implement these practices effectively, and the critical role that automation tools like Fuze play in maintaining order.

The Essentials of Configuration Management for Embedded Firmware

Configuration management in embedded firmware is the disciplined practice of ensuring that every aspect of the firmware build process—from source code, build environments, and dependencies to build artifacts and release statuses—is meticulously tracked and documented. The goal is to create a repeatable, fully traceable, and auditable process that ensures consistency and quality across all stages of firmware development and delivery.

Key Elements to Track for Each Firmware Build

CM should set you up to fully reproduce a build – bit-exact (except for any purposeful dynamic elements).

Let’s start with what information needs to be tracked to ensure proper CM.

Tracking these details ensures that the build process is fully reproducible. If a bug is discovered in the firmware, knowing precisely who built it, when, and with what tools can be crucial for debugging and fixing the issue.

The Build

• Who: Identify the person or automated system that initiated the build.
• When: Document the exact date and time the build occurred.

Pro Level:

• Build Command(s): Capture the exact commands and parameters used to initiate the build. Arguments, options, and input files all affect the build output.

Source

• Source CommitIDs and Branch Names: Document the specific commitIDs from all source repositories. This includes any build tools and config files (memory map, etc) that are tightly coupled to your source code. If branch names are important in your vernacular, then record them as well.
• Tags: Tag your repo(s) and record those values.

Pro Level:

• Diff/Patchset: CommitIDs can disappear. Now what? Branches get deleted, and the associated commitID’s disappear with them. You can/should create a diff/patchset with each build against a tag regularly timed tag.

Tools and Environment

• Toolchain: Record the versions of compilers, linkers, and any other tools used during the build process.
• Build Environment: Machine and HostOS details.
• Script/ConfigCommitIDs: Document the commitIDs of any build scripts or configuration files loosely coupled to the source repositories. For example, you may have a “utilities” repository that isn’t part of the source code repo but contains build utilities.

Pro Level:

• Dockerfiles and Containers: Use containers for the production build toolchain and then put its dockerfile or the container itself under CM.

Dependencies:

• Standard Libraries: Record version/config info for all third-party and standard libraries.
• Linked Package Libraries: Record the version information for all custom and self-built libraries linked in the firmware image.

Pro Level:

• Source for Linked Package Libraries: Extend your traceability back through the source of the linked binary library. Now you can build a dependency traceability graph all the way back to the source.

Build Package:

• Package Contents: In addition to a particular firmware image, create a traceable package of all images and supporting files (configuration, documentation, etc) that comprise a particular release.
• Package Structure: Document the package structure so that any deployment/programming tools know where to find the important files.

Pro Level:

• Test Results: Include a reference to the test results or the test results themselves of the build package.

Release Status:

• State: Document the state of the release.
• Who: Identify the person who changed the release state
• When: Document when it happened.

Pro Level:

• Delivery Status and Traceability: To whom, by who, when, and what method.

Commonly Overlooked Aspects of Configuration Management

Even with the best intentions, certain aspects of CM are often overlooked:

• Complete Environment Documentation: Teams often fail to fully document the build environment, including specific versions of the operating system, installed tools, and environmental variables. This can lead to inconsistencies and bugs that are difficult to trace back to their source.
• Missing CommitIDs: CommitIDs can be deleted.
• Comprehensive Artifact Management: It’s easy to focus solely on the final firmware binary, but all intermediate artifacts and logs should also be tracked and stored. These can be invaluable for debugging and future maintenance.
• Single Source of Truth: CM data can become fragmented across different configuration management methods and teams, leading to inconsistencies and gaps. Establishing a centralized location where all CM data is stored and accessible is crucial for maintaining integrity.

Creating a Single Source of Truth

A Single Source of Truth (SSOT) is vital for ensuring that all team members have access to consistent and up-to-date configuration data. This can be achieved through centralized systems that integrate all aspects of CM, from source code and dependencies to build artifacts and test results.

Methods to Implement SSOT:

1. Manifest Files: These files list all components, their versions, and configurations used in the build. Manifest files serve as a quick reference and can be stored in the same repository as the source code.
2. Jira Tickets: Using issue tracking systems like Jira helps log every change and decision made throughout the development process. By linking Jira tickets to specific commits, builds, and releases, you can maintain a traceable history that spans the entire project.
3. Databases: A dedicated CM database can store all configuration items, their versions, and relationships. This structured approach ensures that all relevant data is stored in a consistent, searchable format.

Pro Level:

Use a tool that automates the entire configuration management process from build through test and delivery and then allows easy, yet secure access to all of the CM information for each build.

Automating Configuration Management with Fuze

Automation plays a critical role in maintaining effective CM, especially as projects scale. Fuze is an automation tool designed specifically for embedded firmware development, helping teams to manage and streamline the CM process.

Key Features of Fuze for CM Automation:

• FuzeID: Every build managed by Fuze is tagged with a unique identifier, the FuzeID. This ID encapsulates all relevant data about the build, including the source commit ID, toolchain versions, build commands, dependencies, test results, and more. The FuzeID provides a complete traceable history for each firmware version, ensuring that it can be reproduced and analyzed at any time.
• Centralized Management with Distributed Operation: Fuze is a distributed build executive that can execute locally or in cloud infrastructure, but it centralizes all elements of the firmware build and configuration management process. This helps in maintaining a single source of truth and ensures that all team members have access to consistent data.
• Environment Replication: Fuze supports the creation of reproducible build environments using containerization. This ensures that the same environment can be used across different systems, reducing the risk of environment-related bugs.
• Automated Configuration Management: Fuze generates and tracks all of the information described above for each build. These reports are invaluable for maintaining accountability and ensuring that the build process meets all required standards.

Conclusion

Effective configuration management (CM) is crucial for the success of embedded firmware development. In an industry where the stakes are high and the environments are complex, CM serves as the backbone that keeps every aspect of the development process organized and traceable. By ensuring that each firmware build is meticulously documented—from who initiated the build to the exact tools and environments used—you safeguard against the chaos that can arise in embedded systems.

CM is not just about tracking versions; it’s about creating a system where every build is fully reproducible, where every issue can be traced back to its source, and where every deployment is precise and error-free. In this increasingly complex landscape, automation tools like Fuze elevate CM practices by centralizing and streamlining these processes, ensuring that your firmware is not only reliable but also fully auditable.

As embedded systems continue to evolve, robust configuration management is no longer optional—it’s essential. Whether you’re managing a small project or a large-scale deployment, the ability to control and replicate every aspect of your firmware builds is key to maintaining quality, reliability, and innovation.