Onboarding into Older Codebases

Sally Lait joins Robby Russell on Maintainable to explore software maintainability through a different lens… not just code quality, but how teams work together over time.

Sally is a fractional technology leader and advisor with more than two decades in the industry. You can follow her on LinkedIn or Mastodon.

They start with a familiar question: what makes software well maintained? Structure and standards matter, but Sally shifts the focus to signals around the edges… documentation, onboarding speed, knowledge sharing, and especially how confident people feel making changes.

That confidence becomes the thread throughout the conversation.

Teams with high confidence move faster and adapt more easily. Teams with low confidence hesitate, avoid parts of the system, and struggle to make progress… regardless of what the code looks like.

Robby and Sally also dig into why maintenance work often struggles to get traction. It rarely speaks for itself. Leaders need to connect it to outcomes the business already cares about… risk, hiring, delivery speed, and long-term sustainability.

Sally references a LeadDev panel she moderated on why maintenance still feels “stuck in 2015”: Why Software Maintenance Is Stuck in 2015.

They also discuss modernizing legacy systems and moving away from long-standing in-house software… work that is rarely just technical. It requires trust, clear communication, and navigating the emotional attachment teams have to what they’ve built.

The episode closes with advice for engineers joining older codebases: stay curious, build relationships early, and use onboarding gaps as opportunities to improve things for the next person.

Episode Highlights

[00:01:02] What Makes Software Maintainable: Technical quality matters, but cultural signals often tell the deeper story.

[00:05:45] Why Progress Still Feels Slow: Even with improvements, teams can feel stuck due to perception gaps.

[00:07:30] Communicating Small Wins: Lack of visibility into incremental progress impacts morale and confidence.

[00:12:40] Influencing Without Manipulating: Maintenance work needs to be framed in business terms.

[00:16:00] Technical Debt as a Hiring Problem: Outdated systems affect recruiting and retention.

[00:20:22] Modernizing a Siloed System: Unlocking legacy data required both technical and organizational change.

[00:26:55] Building Trust for Change: Surprise proposals fail… alignment takes time.

[00:32:39] Letting Go of “Our Baby”: Replacing systems involves emotional and cultural dynamics.

[00:46:25] Joining an Older Codebase: Practical advice for onboarding and building confidence quickly.

Resources Mentioned

• Sally Lait
• Sally Lait on LinkedIn
• Sally Lait on Mastodon
• Why Software Maintenance Is Stuck in 2015 (LeadDev Panel)
• Lara Hogan
• The Murderbot Diaries by Martha Wells
• Death of the Author by Nnedi Okorafor
• Sally’s Reading & Reviews Site

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