Building software
Ship a feature in an existing codebase
Write, test and review code in a repo that already has conventions.
Best tools for this task
Every pick scored out of 10 on how accurate its output is, how fast it gets you a usable result, and how cheap it is to run. Reorder the list by whichever matters most.
Most accurate
Claude 9.4
Fastest to a result
Claude 9.5
Cheapest to run
GitHub Copilot 8.1
1. GitHub Copilot
Cheapest sanctioned option and lives inside existing IDEs.
- Accuracy
- 8.9/10
- Speed
- 8.4/10
- Cost
- 8.1/10
2. Claude
Best at explaining unfamiliar code before you change it.
- Accuracy
- 9.4/10
- Speed
- 9.5/10
- Cost
- 6.2/10
3. Cursor
Whole-repo context and multi-file edits, the fastest real workflow.
- Accuracy
- 9.2/10
- Speed
- 8.7/10
- Cost
- 6.2/10
How to do it, step by step
- 1
Write the test or acceptance criteria before generating the implementation.
- 2
Keep changes to one concern per commit so review stays possible.
- 3
Ask for the risky edge cases the diff does not cover, then handle them.
What usually goes wrong
Generated code copies patterns, including insecure ones. Review auth and data access by hand.