Nexa Clip

About

Nexa Clip is a clipboard manager with an identical-looking interface on Windows, macOS and Linux. It was built for people who copy and paste dozens to hundreds of times a day while moving between OSes: developers, planners, translators and operators. The product is defined in one line: an always-running tool that keeps everything you copy encrypted, shows it in the same interface on three OSes, and brings it back in one step on any of your devices. In short: "the power of Ditto, the lightness of Maccy and the portability of CopyQ, in a single interface we draw ourselves, with no framework."

We surveyed six competing products and settled on three differentiators. ① A fully identical interface on 3 OSes: CopyQ has the Qt look and EcoPaste and PasteBar use the OS WebView, so their interfaces differ by OS, whereas Nexa Clip uses neither OS widgets nor a UI framework and draws every pixel itself. ② Encryption by default: history is stored encrypted on your PC (on by default · 0 of the six products surveyed have this on by default), and transfers between devices are sealed with end-to-end encryption. ③ Always-on budget gates: because the program runs 24 hours a day, idle memory, build size and startup time are enforced by gates. This one item is what killed 1Clipboard (Electron).

Capture covers text, images (PNG preserved + thumbnail), file and folder paths and HTML/RTF formatting, and it preserves the native formats placed by Word, PowerPoint and Excel under their original names, so PPT shapes pasted again go in as shapes rather than pictures. The app you copied from (the source app) is recorded as well, and copying the same content again moves the existing item to the top instead of creating a new one. It respects the "do not record" marker sent by password managers and does not capture that content at all, and there is also a list of excluded apps and a toggle to pause capture. The image parser is not linked into the main program; images are decoded only in a separate, isolated process (nclip-imgdec).

The fastest route is the quick popup. Press Shift+Alt+C and a popup appears at the cursor position, ready for you to type in the search bar. Search also works while Korean characters are still being composed. Enter pastes as-is · Shift+Enter as plain text · Ctrl+Enter as an object · Alt+Enter the path only. Ctrl+1~9 (⌘1~9 on macOS) instantly picks an item by its visible order, Ctrl+P (⌘P on macOS) pins or unpins an item without closing the popup, and the paste stack lets you collect several items and use them in order. The popup takes focus and always gives it back: after you pick an item, it is pasted into the window you were in by key injection, and Shift+Alt+X pastes the current clipboard without formatting and then restores the original.

The main window consists of a vertical toolbar on the left (Pin · Delete · Copy · Copy as plain text · Hide duplicates · Preview · Always on top · Settings), a search bar, a list and a preview. Alt+1/2/3 switches between three view modes: Normal view (number · multiple lines · image thumbnails) · Compact view (type icon · source app) · Single-line view. Search has three modes, Exact · Fuzzy (default) · Regex, and looks through the content as well as the labels using an in-RAM index. In the preview, a restricted rich-text renderer draws weight, color, lists, indentation, inline images and terminal colors (ANSI), while script and network access stay at 0. The settings window (Ctrl+,) is made of cards in 5 groups (General · Clipboard · Appearance · Sync · Advanced); you find items with search (matching Korean by individual jamo) and changes apply instantly. Rarely used items are hidden behind the Advanced switch, and since v0.2.5 you can view only the items that differ from their defaults and export, import and edit settings as JSON.

Storage uses append-only encrypted segments + content-addressed blobs. ChaCha20-Poly1305 envelopes use domain-separated keys per file type, and the device key (device.key) wraps the master key. Retention limits are available for all three of item count, age and size, pinned items are exempt, and heavy native formats are reclaimed first through per-representation lifetimes. Settings include clearing history on exit, hiding sensitive sources such as browser password pages, and Clear all history (twice within 2 seconds), and files that hold secrets are made readable only by their owner (0600). The in-memory layer unloads cold content immediately and keeps thumbnails in an LRU cache, which cut startup RSS from 82MB to 18.7MB, and lazy blob loading took startup time from 1.8 seconds to 107ms. Since v0.2.3, when a copy exceeds the per-item size limit (32MB by default), non-essential representations are not stored, largest first, and on Windows sizes are checked first so that representations to be dropped are never read.

Sync is optional and off by default. To turn it on, you fill in just two lines: an ID (handle) and a pairing password. The password never goes to the server; it is only input for deriving the meeting point (rendezvous ID) with PBKDF2, so nobody who does not know it can compute where your devices meet. Devices that meet appear in the device list, and the clipboard is exchanged only after you visually confirm that the 6-digit verification codes on both screens match and approve (1 approval per device · revocable at any time). What propagates is plain text and PNG images; received items are labeled with their source (⇄ device name) and are never sent back. On the same Wi-Fi, devices connect without a server (None) through UDP beacons + direct TCP, and devices on other networks go through a relay server; on either path the Noise end-to-end session is established only between the two devices, and the server sees only envelopes. Files travel too since v0.1.4: only the path list is sent at copy time, and at the moment you paste on the receiving device the contents are fetched from the source device and pasted as real files. Files of 50MB or less are slowly prefetched in the background, and received files stay in the Nexa Clip folder under your Downloads folder for reuse. File cuts and formatting (HTML/RTF) are not sent. With three or more devices, since v0.2.2 approved devices tell each other which devices they know, so devices on different networks that could not meet directly can still be found and connected. Devices found this way also exchange no clipboard items or files until approved.

The relay server is not included in Nexa Clip. It is a separate program, nexa-beepd, distributed by the Nexa Beep project, and the app defaults to the official SosomLab server (beepd.sosomlab.com:47300). The server public key is pinned on first connection (TOFU), and if it changes the app stops connecting and warns you. Nexa Beep uses the same server, but the rendezvous domain string and Noise prologue differ, so the two apps cannot see each other on the server (application isolation — by structure, not by check code). Traffic safeguards include exponential retry backoff (Standard 5 seconds→5 minutes), 4 concurrent handshakes, a 30-second cooldown for failed IPs and per-peer receive budgets.

We do not hide what does not work yet. There is no code signing, so macOS Gatekeeper and Windows SmartScreen warnings appear (the brew Cask removes the quarantine flag at install time), and for the same reason the Chocolatey installer is stuck in moderation due to antivirus detections (the portable package is approved). The winget 0.1.6 submission has not been merged yet. macOS needs the Accessibility permission for paste injection, and Linux (GNOME/Wayland) needs one portal approval each for global hotkeys and key injection. Sync does not carry formatting yet, Linux assets are x86_64 only, and mobile receiving is the lowest priority.

Distribution covers 5 targets (Windows x64 and ARM64, macOS Apple Silicon and Intel, Linux x64) × 2 channels, installer and portable (15 assets, including .rpm, package manifests and SHA256SUMS). Pushing a tag publishes automatically, and the Homebrew tap follows releases automatically. On Linux, the signed APT and DNF repositories at pkg.sosomlab.com are updated automatically with each release. Linux builds are linked against glibc 2.17, so they run regardless of distribution. The underlying structure was taken from Nexa Beep (crate boundaries · rasterizer · relay stack) and Nexa Dir (controls · virtualized list) and absorbed under this project's name. Under the PolyForm Noncommercial 1.0.0 license, personal and non-commercial use is free, and commercial use requires a separate paid license (contact kiros33@sosomlab.com). Since v0.2.0, Settings › Advanced › About lets you check the license status, copy a request code and install a license file, and verification is done offline only.