The Day Our Pipeline Failed, And Exposed a Two-Year-Old Mistake

Sometimes the problem at the surface isn’t the actual problem, it’s just the symptom that finally made the real issue visible.

Last week, our production deployment pipeline for backend-api suddenly started failing with a cryptic error message:

[helm-secrets] File is not encrypted: /tmp/helmfile-embdedded-secrets-3235971632.yaml.enc
Error: plugin “secrets” exited with error

This was particularly puzzling because nothing had changed in our Helm configuration files for months. The deployment had been working perfectly fine until it suddenly wasn’t. What followed was a multi-day debugging journey that revealed an important truth: the problem at the surface is rarely the actual problem. What appears to be a deployment failure caused by a recent change often turns out to be something much deeper, waiting for the right conditions to reveal itself.

The Mystery Begins

The error appeared after every deployment attempt failed with the same error about unencrypted files, even though we were certain our secrets were properly encrypted with SOPS.

The confusing part? Our development environment deployments were working fine. It was only staging and production that failed.

The Investigation

I started digging. Initial theories centered around the recent codefresh ( CI/CD platform ) configuration changes, leading to an attempted revert. When that didn’t work, we knew something deeper was going on.

The breakthrough came when we examined the exact structure of our Helmfile configuration. Here’s what our staging release looked like:

releases:
  - name: backend-api-staging
    values:
      - ../rules/staging.yaml
    secrets:                   
      - ../secrets/staging.yaml
      - defaults:              # Problem here!
          team: ops-workflows
      - env:                   # Problem here!
          NODE_ENV: “production”
      - applications:          # Problem here!
          - name: backend-api

Notice anything wrong? We had inline, unencrypted data nested directly under the secrets: section. While ../secrets/staging.yaml was properly encrypted, the inline defaults, env, and applications blocks were plain text.

The Root Cause

The culprit was a helm-secrets plugin update from three weeks prior. The plugin maintainers had added stricter validation for encrypted files. Here’s what changed:

Old code (lenient):

if ! content=$(decrypt_helper “${encrypted_filepath}” “auto” “${output}”); then
    fatal ‘File is not encrypted: %s’ “${encrypted_filepath}”
fi

New code (strict):

# Append underscore to preserve trailing newlines
if ! content=$(decrypt_helper “${encrypted_filepath}” “auto” “${output}” && printf ‘_’); then
    fatal ‘File is not encrypted: %s’ “${encrypted_filepath}”
fi

# Remove underscore
content="${content%_}"

The addition of && printf ‘_’ made the validation chain stricter. Now decrypt_helper must succeed completely, or the entire chain fails. Previously, the plugin was more forgiving about inline unencrypted data in the secrets section, it would silently pass through. The new version correctly identified this as a configuration error.

Understanding the Failure Chain

To truly understand what was happening, we need to trace the execution flow when Helmfile processed our staging configuration:

Step 1: Helmfile processes staging.yaml

Helmfile encounters our release configuration with both encrypted files and inline unencrypted data under secrets::

releases:
  - name: backend-api-staging
    values:
      - ../rules/staging.yaml
    secrets:                   
      - ../secrets/staging.yaml
      - defaults:              # ❌ Unencrypted inline data
          team: ops-workflows
      - env:                   # ❌ Unencrypted inline data
          NODE_ENV: “production”
      - applications:          # ❌ Unencrypted inline data
          - name: backend-api

Step 2: Helmfile calls helm-secrets plugin to decrypt

Helmfile creates a temporary file containing all the secrets section content and passes it to the helm-secrets plugin for decryption.

Step 3: Helm-secrets validation (NEW stricter code)

The plugin runs its validation logic:

decrypt_helper() {
    if ! backend_is_file_encrypted “${encrypted_file_path}”; then
        return 1  # ← File not encrypted, returns failure
    fi
    ...
}

# In decrypt():
if ! content=$(decrypt_helper ... && printf '_'); then
    # ← decrypt_helper returned 1, so && chain fails
    fatal 'File is not encrypted: %s' "${encrypted_filepath}"
    # ← ERROR THROWN HERE
fi

The backend_is_file_encrypted check fails because the temporary file contains unencrypted inline data. The decrypt_helper returns 1 (failure), and because of the && printf ‘_’ chain, the entire validation fails immediately.

Step 4: Helmfile fails with error message

[helm-secrets] File is not encrypted: /tmp/helmfile-embdedded-secrets-2093833071.yaml.enc
Error: plugin “secrets” exited with error

The error message is technically accurate but misleading, it’s not that our SOPS file isn’t encrypted, it’s that Helmfile bundled unencrypted inline data with it, and the stricter validation caught this configuration mistake.

Why It Worked Before

For nearly two years, our misconfigured secrets section worked because:

1. The helm-secrets plugin was more lenient about file validation
2. The inline data happened to be structured in a way that didn’t trigger errors
3. The actual encrypted SOPS file was still being processed correctly

We had essentially been living with a configuration bug that worked until it didn’t.

The Red Herrings

What made this issue particularly challenging was the number of false leads:

Red Herring #1: The Recent Configuration Change

The failure appeared immediately after updating our Codefresh configuration to address stale Docker images. This change had been applied successfully across multiple repositories, making it the obvious suspect. We even tried adding the CF_BRANCH environment variable, thinking it might be related to branch detection. Nothing worked.

Red Herring #2: The Timing

The deployment had worked flawlessly for two years. When something breaks suddenly after that long, you naturally assume something changed in your code. We looked at recent commits, recent PRs, and recent dependency updates. Everything pointed to our changes being the problem.

Red Herring #3: Environment-Specific Failures

Development deployments continued to work perfectly while staging and production failed. This suggested an environment-specific configuration issue, sending us down another investigative path. The real reason? Our dev configuration happened to have its inline values in the values: section (correct) rather than the secrets: section (incorrect).

All of these clues pointed in the wrong direction, obscuring the real issue lurking in plain sight.

The Actual Fix

Once we identified the problem, the fix was straightforward. We needed to move the inline unencrypted data out of the secrets: section and properly format the SOPS file:

Before (incorrect):

releases:
  - name: backend-api-staging
    values:
      - ../rules/staging.yaml
    secrets:                   
      - ../secrets/staging.yaml
      - defaults:              # Unencrypted inline data
          team: ops-workflows
      - env:                   
          NODE_ENV: “production”

After (correct):

releases:
  - name: backend-api-staging
    values:
      - ../rules/staging.yaml
      - defaults:              # Moved to values section
          team: ops-workflows
      - env:                   
          NODE_ENV: “production”
    secrets:                   
      - ../secrets/staging.yaml  # Only encrypted files here

The secrets: section should only reference encrypted SOPS files, never inline plaintext configuration.

Lessons Learned

1. Plugin Updates Are Code Changes Too

We tend to think of dependency updates as safe, especially for tools rather than application code. But plugins like helm-secrets are part of your infrastructure’s critical path. A plugin maintainer fixing a bug or adding stricter validation can surface issues you didn’t know existed.

2. Silently Passing Bad Configuration Is Worse Than Failing

The old helm-secrets behavior, accepting unencrypted data in the secrets section, was actually a bug that got fixed. While the immediate pain of deployment failures was real, the stricter validation is objectively better. It forced us to fix a configuration that was wrong all along.

3. Working Code Isn’t Necessarily Correct Code

Just because something works doesn’t mean it’s right. Our configuration had been incorrect for two years, but it worked due to lenient validation. This is technical debt that accumulates silently until something changes the conditions that allowed it to exist.

4. The Surface Problem Is Rarely the Real Problem

This deserves repeating because it’s the core lesson from this incident: the problem you see is almost never the problem you have.

We spent significant time investigating the recent configuration changes, convinced they were the culprit. The surface-level evidence was compelling, deployments broke immediately after the change, so naturally that change must be the cause. But the actual issue dated back two years to when someone (probably copying from another repo) nested inline values under secrets: instead of values:.

The recent change didn’t cause the problem; it just happened to be present when the plugin update exposed the underlying issue. If we had started our investigation with the assumption that surface symptoms might be misleading, we could have dug deeper into the configuration structure earlier rather than chasing red herrings.

This pattern appears constantly in software engineering: the error message points to one thing, but the root cause is something entirely different. The stack trace shows a null pointer exception, but the real problem is incorrect initialization logic three layers up. The deployment fails after a recent commit, but the actual issue is a two-year-old misconfiguration that only now matters due to changed validation rules.

When debugging, always ask: “What if the obvious answer is wrong? What if this problem has been here all along, just waiting for the right conditions to surface?”

5. Good Error Messages Matter, But Context Matters More

The error message “File is not encrypted” was technically accurate but misleading. The file in question was a temporary file created by Helmfile that included both our encrypted secrets and the inline unencrypted data. Without understanding the full context of how Helmfile and helm-secrets interact, the error pointed us in the wrong direction.

Prevention Strategies

How can teams avoid similar issues?

1. Monitor Upstream Dependencies: Keep track of updates to critical infrastructure plugins. The helm-secrets changelog would have revealed the stricter validation changes.
2. Validate Configuration Explicitly: Don’t rely on tools to silently accept invalid configuration. Use linters and validators that enforce correct structure, even if the tools themselves are lenient.
3. Test Changes in Production-Like Environments: Our dev environment passed because its configuration happened to be correct. If we had tested the actual staging configuration changes in a dev environment first, we might have caught this sooner.
4. Document the “Why” Behind Configuration: When someone two years from now sees secrets: and thinks “I’ll just add my config here,” they should have comments or documentation explaining why certain values must be encrypted and others must not.
5. Embrace Failures That Expose Problems: Yes, this failure blocked deployments and required immediate attention. But it also forced us to fix a misconfiguration that could have caused more subtle issues down the line, like accidentally exposing secrets or confusion about what should and shouldn’t be encrypted.

Conclusion

The deployment didn’t really break, it was broken all along. What we experienced was a long-hidden misconfiguration finally being exposed by stricter validation in an upstream dependency. The real problem wasn’t the helm-secrets plugin update; it was our incorrect use of the secrets: section two years ago.

These kinds of issues are insidious precisely because they work until they don’t. They’re technical debt that accumulates silently, invisible until circumstances change. The lesson isn’t to avoid dependency updates or to mistrust tools that become stricter. The lesson is to recognize that “working” and “correct” aren’t always the same thing, and that failures can be valuable teachers.

Sometimes the best bug fix is the one that makes your existing bugs impossible to ignore.