Technical Debt Web App Audit (2026)

The verdict in three sentences

A technical debt audit costs between 3,000 and 10,000 EUR (excl. VAT) in 2026 and replaces intuition ("our code is fragile") with objective metrics. The three most revealing are test coverage, cyclomatic complexity and the number of obsolete or vulnerable dependencies. The audit is useless unless it leads to a prioritised repayment plan costed in person-days, with the cost of inaction shown alongside.

The metrics that really matter

A good audit doesn't produce a 200-line ESLint list, but a few indicators correlated with business risk.

A dependency not updated in 3 years isn't just cosmetic: it's an entry point for an attacker and a blocker for recruiting developers.

What inaction costs

Technical debt is paid as interest: every month without repayment makes evolution slower and riskier. Here's how to cost this invisible burden.

On a team of 4 developers, the "debt tax" commonly represents 25 to 40% of development time wasted working around the existing code.

Mini case study

Sophie, CTO of an HR SaaS vendor in Lille, hesitates before launching a 90,000 EUR (excl. VAT) rebuild. She first commissions an audit at 6,500 EUR (excl. VAT). Result: 18% test coverage, 47 obsolete dependencies, 4 critical CVEs, and 3 modules concentrating 70% of bugs.

The audit proposes a three-wave plan: secure the CVEs (5 days), raise coverage on the 3 critical modules (18 days), modernise dependencies (12 days) — i.e. 35 person-days ≈ 21,000 EUR (excl. VAT). Rather than a full 90,000 EUR rebuild, Sophie repays targeted debt for 27,500 EUR (audit + plan), cuts bugs by 75% and postpones the rebuild by two years. The ROI of the audit alone: 16,000 EUR saved in the first year.

FAQ

How long does a technical debt audit take? Between 5 and 15 working days depending on codebase size. We combine automated static analysis (SonarQube, dependency tools) and human review of critical areas.

Can you audit without full code access? Yes, under NDA on a read-only repository. For security metrics, access to the dependencies (package.json, requirements.txt) already reveals the essentials.

Must all debt be repaid at once? No. We prioritise by impact/effort ratio: first security vulnerabilities, then bug-concentrating modules, finally developer comfort. The rest can stay documented and accepted.

How do you avoid recreating debt afterwards? Through automatic guardrails: minimum coverage threshold in CI, blocking of vulnerable dependencies, mandatory code review. These rules take 2 to 4 days to set up and pay off within weeks.

Does the audit replace the internal team's opinion? No, it objectifies it. Developers often know where the problems are; the audit quantifies their severity and gives management a solid budget argument.

Let's scope your project. Send us repository access and your main concern (security, slowness, bugs): we'll deliver a costed audit with a prioritised repayment plan. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.