V3.0 Mod Compatibility — What Breaks in Dead Hot Summer (And What To Do)

Updated June 12, 2026 from the official release notes. PC experimental lands June 15; expect the mod-update wave to start that week.

Every major 7DTD update breaks mods; V3.0 breaks them in documented, specific ways, because The Fun Pimps shipped real modding-infrastructure changes alongside the sandbox update. If you run a modded server or maintain a mod, here is exactly what the release notes say changes, what it means, and the safe sequence for update week.

The documented breaking changes

  • Localization.txt → Localization.csv. Renamed to match its actual contents. Mods shipping localization files need the rename; tooling that targets the old filename stops finding it.
  • entitygroups.xml returns to proper XML elements. The previous text-based format is still supported "currently" — which is modder-speak for migrate now, the compatibility shim will not live forever.
  • Code mods: one assembly, publicized. You now reference only the game's core Assembly-CSharp.dll, and because the code passes through a publicizer, code that overrides vanilla methods may need those overrides made public. Most C# mods need at least a recompile.
  • XUi framework overhaul (the big one for UI mods). A new XML binding system moves control from code to XML; new views (video, scrollbar, scrollview); controls.xml renamed to templates.xml; the folder renamed to XUi_InGame; the force_hide attribute removed in favor of visible; tweens controllable from XML. UI-heavy mods (HUDs, bigger backpacks with custom windows, quest trackers) face real porting work, not a recompile.

What this means for modded servers

  • Assume nothing survives update day. The XUi rework alone touches most popular server-side UI conveniences. The usual wave applies: big mods within days, mid-size within weeks, abandoned never.
  • Overhauls will lag longest. Darkness Falls-class total conversions touch entitygroups, localization, code, and UI at once — every changed surface. Overhaul servers should plan to stay on V2.6 until their overhaul publishes a V3.0 build (saves do not load backward, so the move is one-way).
  • Some mods become obsolete — in a good way. A real fraction of the server-mod ecosystem exists to do what the 150 sandbox options now do natively (loot abundance, zombie speeds, headshot rules, death penalties). Before porting a settings mod, check whether V3.0 just shipped it as a checkbox.
  • The safe sequence: export your mod list → classify critical / nice-to-have / replaced-by-sandbox-options → wait for critical mods' V3.0 releases → test on a copy → then move the community save. Our SandboxCode guide covers the config side of the same migration.

For mod authors: the priority order

  • Week one: rename localization, recompile against the publicized assembly, fix any override visibility errors — that revives non-UI mods fastest.
  • Week two: entitygroups to proper XML (do not lean on the deprecated text format).
  • The long tail: XUi ports. The new binding system is documented on the official wiki, and the consolidation (shared attributes across views, rects over panels) genuinely reduces duplication once ported — the pain is front-loaded.

Timing

Experimental June 15; stable follows the experimental cycle. Mod authors can begin porting against experimental immediately, which historically means the big mods are ready near stable day. Track overall V3.0 status on the live tracker.

Sources