Writing unit tests
Software Engineer · Backend Developer
“Writing unit tests” (Software Engineer) was largely replaced by AI in 2026, after AI entered in 2023.
AI enters
2023
Largely replaced
2026
Replacement progress
100%
Technology / key factor
AI-generated tests
What this task is
Writing unit tests for individual functions and modules that cover normal inputs, boundary values and error cases, so that later code changes don't silently break behavior that already works.
How AI replaces it
Since 2023, AI tools read a function's implementation, generate test cases, fill coverage gaps and rerun until tests pass. By 2026, most unit tests are AI-generated, with people only adding what's missing.
What stays human
Engineers decide which behaviors truly matter, check that AI-written tests aren't simply mirroring the implementation, and set the overall testing strategy for critical business logic and risky code paths.
Other Backend Developer tasks
All Software Engineer tasks →Boilerplate / API endpointsReplaced
2022 → 2026 · Code completion → coding agents
Implementing business logicBeing replaced
2025 → 2030 · Autonomous coding agents
System architectureWill be replaced
2028 → 2035 · Balancing requirements and constraints
Clarifying requirements, cross-team communicationWill be replaced
2029 → 2037 · Depends on organizational context