Legacy vs Regular Builds in Electerm: What's Different and How to Choose

On the download page or GitHub releases you will see almost every Linux file twice — once plain, once with -legacy — plus a win7 archive on Windows and a mac10 dmg on macOS. Same version number, similar size, different file. Which one do you need?

Short answer: same electerm, different runtime base. Regular builds are for modern systems. Legacy builds are for older systems. Pick wrong and the app just won't start — pick right and everything works identically.

The 30-second rule

Your system	Download this
Windows 10 / 11	regular win-x64 (Intel/AMD) or win-arm64 (Snapdragon / ARM)
Windows 7 / 8 / 8.1	win7.tar.gz (the only Windows legacy build)
macOS 11+ (including all Apple Silicon Macs)	regular mac-arm64.dmg (M1/M2/...) or mac-x64.dmg (Intel)
macOS 10.x (10.13 / 10.14 / 10.15)	mac10-x64.dmg
Modern Linux (Ubuntu 20.04+, Debian 11+, Fedora / Arch recent, ldd --version shows glibc 2.34+)	regular (no -legacy)
Old Linux (Ubuntu 18.04, UOS / Kylin old releases, CentOS 7-era, ldd --version shows glibc < 2.34) or you get a GLIBC_2.34 not found error	-legacy build
LoongArch (Loongson) UOS / Kylin	new-world system → regular loong64, old-world system → -legacy (ask your distro vendor if unsure, see below)

If you are on a mainstream, up-to-date OS, always take the regular build. Only reach for legacy when the regular one refuses to run or your OS is on the left side of the table above.

What -legacy actually means

Electerm is an Electron app: your SSH sessions, SFTP panel, themes and AI assistant run as JavaScript, but they sit on top of a Chromium + Node.js runtime that talks directly to the OS.

Every year Chromium and Electron drop support for older OS versions:

• Electron 23+ dropped Windows 7/8/8.1 (follows Chromium 109+).
• Newer Electron needs newer macOS SDKs, so old macOS 10.x can't run it.
• Newer Linux builds are compiled on newer distros, so they require glibc 2.34+. glibc is forward-compatible only: a binary built on old glibc runs on new glibc, but a binary built on new glibc refuses to run on old glibc.

So electerm ships two flavors of the same app code, same version number, same features:

• Regular: built with the current Electron on a modern base. Best performance, newest Chromium security fixes, hardware acceleration as expected.
• Legacy (-legacy, win7, mac10): built with an older-compatible Electron / older build base so it still starts on Windows 7, macOS 10.x, and glibc as old as 2.17 (Ubuntu 18.04, UOS, Kylin, CentOS 7-era). For LoongArch it additionally means the old-world ABI vs the new-world ABI.

Nothing about your bookmarks, sync (GitHub gist / WebDAV / electerm cloud), quick commands, or AI features changes between the two. The version number is identical — e.g. electerm-5.5.66-linux-x86_64.rpm and electerm-5.5.66-linux-x86_64-legacy.rpm are both v5.5.66, released the same day.

Side effect you may notice: legacy files are often smaller (in v5.5.66 the regular x86_64 AppImage is ~121 MB, the legacy one ~95 MB). That is just the different Chromium base, not missing features.

How to tell the files apart

File names follow electerm-<version>-<platform><ext>:

• Windows: electerm-5.5.66-win-x64-installer.exe = regular installer. electerm-5.5.66-win7.tar.gz = Windows 7/8 legacy (extract and run, no installer). There is no -legacy suffix on Windows — win7 is the legacy marker.
• macOS: electerm-5.5.66-mac-arm64.dmg / mac-x64.dmg = regular. electerm-5.5.66-mac10-x64.dmg = macOS 10.x legacy (Intel only — there was no Apple Silicon back then).
• Linux: anything with -legacy before the extension is legacy, e.g. electerm-5.5.66-linux-amd64-legacy.deb vs electerm-5.5.66-linux-amd64.deb. This applies to .deb, .rpm, .AppImage and .tar.gz, across x64, arm64, armv7l and loong64.
• LoongArch special case: you will see both linux-loong64.deb and linux-loong64-legacy.deb (sometimes also labeled loongarch64). Despite the generic -legacy name, here it means old-world vs new-world system ABI, not just glibc age. The download page labels them "New World" and "Old World".

On the homepage the download tabs already split these for you: x86_64 vs x86_64 Legacy, ARM64 vs ARM64 Legacy, LoongArch64 vs LoongArch64 Legacy, plus a separate Windows 7 arch tab.

How to choose: check your system in 3 commands

Windows

Press Win + R, type winver, Enter. Or Settings → System → About.

• Shows Windows 10 / 11 → regular win-x64-installer.exe (or win-arm64 on ARM laptops like Snapdragon X Elite — check Settings → System → About → System type).
• Shows Windows 7 / 8 / 8.1 → win7.tar.gz. Also use it if you must stay on an unpatched old machine for industrial / lab hardware.

macOS

Apple menu → About This Mac.

• macOS 11 Big Sur or newer → regular dmg matching your chip (Apple Silicon M-series → mac-arm64.dmg, Intel → mac-x64.dmg).
• macOS 10.x (Catalina 10.15 and older) → mac10-x64.dmg. Open after download, drag to Applications, right-click → Open on first run if Gatekeeper complains.

Linux

Run these three:

cat /etc/os-release   # which distro + version, e.g. Ubuntu 18.04 vs 22.04, UOS / Kylin version
ldd --version         # first line shows glibc, e.g. "ldd (Ubuntu GLIBC 2.27...)"
uname -m              # cpu: x86_64, aarch64 (= arm64), armv7l, loongarch64, riscv64, ppc64le

Decision:

1. Map uname -m to the file arch: x86_64 → x64/amd64/x86_64, aarch64 → arm64, armv7l → armv7l, loongarch64 → loong64, plus riscv64 / ppc64le which currently ship regular-only.
2. If glibc is 2.34 or newer (Ubuntu 22.04 ships 2.35, Debian 12 ships 2.36, Fedora 38+ ships 2.37+) → regular build.
3. If glibc is older than 2.34 (Ubuntu 18.04 ships 2.27, many UOS / Kylin old-world releases ship 2.28) → -legacy build. As a rule of thumb: Ubuntu 18 / Debian 9 / CentOS 7-era and contemporary domestic distros = legacy; Ubuntu 20.04+ / Debian 11+ / UOS 1070+ new installs = try regular first.

For LoongArch, glibc alone is not enough. Loongson had an "old world" (pre-standard ABI used by early UOS/Kylin LoongArch releases) and a "new world" (the upstreamed ABI). A new-world binary will not run on an old-world system and vice versa, even with the same glibc. If uname -m says loongarch64 and you don't know which world you have, check your distro's release notes or ask the vendor — then take regular for new-world, -legacy for old-world.

"I picked the wrong one" — symptoms and fixes

Good news: picking wrong never breaks your data. It just fails fast at launch. Switch files and you are done — bookmarks and settings live in your data folder, not in the installer.

Symptom	Cause	Fix
Linux: ./electerm: /lib/x86_64-linux-gnu/libc.so.6: version 'GLIBC_2.34' not found	regular build on old glibc	download the -legacy .deb / .rpm / .AppImage / .tar.gz for your arch
Linux: cannot execute binary file or instant exit	wrong CPU arch (e.g. x64 binary on arm64 Pi)	re-check uname -m, download matching arch
Windows 7: installer won't start, blank window, or missing api-ms-win-* DLL errors	regular build needs Windows 10+	download win7.tar.gz, extract and run
macOS 10.x: "This application requires macOS 11 or later" / won't open	regular dmg needs newer SDK	download mac10-x64.dmg
LoongArch: Exec format error or missing interpreter on an otherwise correct arch	old-world vs new-world mismatch	swap regular ↔ -legacy loong64 build

If the regular build installs but renders oddly on a very old GPU, trying the legacy build is also a reasonable experiment — the older Chromium sometimes behaves better on decade-old graphics stacks.

FAQ

Are legacy builds outdated or missing features? No. Both flavors are built from the same commit and published under the same version. When v5.5.66 ships, all ~40 assets — regular and legacy — ship together.

Are legacy builds less secure? They use an older Chromium base (that is precisely why they still run on old OSes), so the regular build gets newer upstream hardening first. But electerm still patches app-level issues in both, and running the legacy build on an old OS that gets no other current terminal is far safer than running an ancient terminal. If your OS can run the regular build, run it.

Can I switch later? Yes. Uninstall / delete one, install the other. Your data folder, exported JSON, and cloud sync carry over. Many people keep a portable .tar.gz / .AppImage of the other flavor on a USB stick for old lab machines.

What about snap / apt / rpm repos / winget / brew? Package-manager channels track the regular build. If you need legacy, download the file directly from the homepage, GitHub releases, the AtomGit mirror (fast in China), or the releases archive.

Do Android / HarmonyOS / iOS have legacy builds? No — -legacy / win7 / mac10 only exist for desktop (Windows / macOS / Linux). Mobile apps ship per-ABI APKs instead; see How to Install and Set Up Electerm.

Cheat-sheet

• Modern OS → regular (no -legacy in the name). Old OS → legacy (-legacy, win7, mac10).
• Linux tiebreaker is ldd --version: ≥ 2.34 → regular, < 2.34 → legacy.
• LoongArch tiebreaker is old-world → legacy, new-world → regular.
• Same version, same features, same sync — only the OS floor differs. When in doubt, try regular first; if it complains about GLIBC / OS version, grab legacy.

Next: How to Install and Set Up Electerm for per-OS install steps, or the SSH features guide once you are up and running.