The 14-Year Road to encoding/json/v2

Originally published in Japanese at https://zenn.dev/ymotongpoo/books/go-json-v2-history.

For 14 years, starting with Go 1.0, encoding/json shipped with known problems, such as case-insensitive field matching, that were never fixed. This book traces the road to encoding/json/v2, formalized in Go 1.27, through the issues, proposals, Gerrit changes, and standard library source that shaped it.

• Introduction
• What Could Not Be Fixed
• Third-Party Workarounds
• The Origins of v2
• From Discussion to Proposal
• How v1 Sits on Top of v2
• Hands-On Verification
• The Ecosystem After v2
• Why the v2 Approach
• Appendix: References