Add project scaffolding

Makefile, Dockerfile, CI workflow, prettier config, manifests for
Chrome (MV3) and Firefox (MV2), source directory structure, and
minimal test suite. All checks pass.

.dockerignore

@@ -0,0 +1,4 @@
+.git
+node_modules
+.DS_Store
+dist

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[Makefile]
+indent_style = tab

.gitea/workflows/check.yml

@@ -0,0 +1,9 @@
+name: check
+on: [push]
+jobs:
+    check:
+        runs-on: ubuntu-latest
+        steps:
+            # actions/checkout v4.2.2, 2026-02-22
+            - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+            - run: docker build .

.gitignore

@@ -0,0 +1,27 @@
+# OS
+.DS_Store
+Thumbs.db
+
+# Editors
+*.swp
+*.swo
+*~
+*.bak
+.idea/
+.vscode/
+*.sublime-*
+
+# Node
+node_modules/
+
+# Environment / secrets
+.env
+.env.*
+*.pem
+*.key
+
+# Build output
+dist/
+
+# Yarn
+.yarn-integrity

.prettierignore

@@ -0,0 +1,3 @@
+node_modules/
+yarn.lock
+dist/

.prettierrc

@@ -0,0 +1,4 @@
+{
+    "tabWidth": 4,
+    "proseWrap": "always"
+}

Dockerfile

@@ -0,0 +1,15 @@
+# node:22-slim (22.x LTS), 2026-02-24
+FROM node@sha256:5373f1906319b3a1f291da5d102f4ce5c77ccbe29eb637f072b6c7b70443fc36
+
+RUN apt-get update && apt-get install -y --no-install-recommends make && rm -rf /var/lib/apt/lists/*
+RUN corepack enable && corepack prepare yarn@1.22.22 --activate
+
+WORKDIR /app
+
+COPY package.json yarn.lock ./
+RUN yarn install --frozen-lockfile
+
+COPY . .
+
+RUN make check
+RUN make build

LICENSE

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
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+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

Makefile

@@ -0,0 +1,42 @@
+.PHONY: test lint fmt fmt-check check docker hooks build clean dev
+
+test:
+	@echo "Running tests..."
+	@timeout 30 yarn run test 2>&1
+
+lint:
+	@echo "Linting..."
+	@yarn run lint 2>&1
+
+fmt:
+	@echo "Formatting..."
+	@yarn run fmt 2>&1
+
+fmt-check:
+	@echo "Checking formatting..."
+	@yarn run fmt-check 2>&1
+
+check: test lint fmt-check
+
+build:
+	@echo "Building extension..."
+	@yarn run build 2>&1
+
+clean:
+	@rm -rf dist/
+
+dev:
+	@echo "Building in watch mode..."
+	@yarn run build --watch 2>&1
+
+docker:
+	@docker build -t autistmask .
+
+hooks:
+	@echo "Installing pre-commit hook..."
+	@mkdir -p .git/hooks
+	@echo '#!/usr/bin/env bash' > .git/hooks/pre-commit
+	@echo 'set -euo pipefail' >> .git/hooks/pre-commit
+	@echo 'make check' >> .git/hooks/pre-commit
+	@chmod +x .git/hooks/pre-commit
+	@echo "Pre-commit hook installed."

REPO_POLICIES.md

@@ -0,0 +1,182 @@
+---
+title: Repository Policies
+last_modified: 2026-02-22
+---
+
+This document covers repository structure, tooling, and workflow standards. Code
+style conventions are in separate documents:
+
+- [Code Styleguide](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE.md)
+  (general, bash, Docker)
+- [Go](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_GO.md)
+- [JavaScript](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_JS.md)
+- [Python](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_PYTHON.md)
+- [Go HTTP Server Conventions](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/GO_HTTP_SERVER_CONVENTIONS.md)
+
+---
+
+- Cross-project documentation (such as this file) must include
+  `last_modified: YYYY-MM-DD` in the YAML front matter so it can be kept in sync
+  with the authoritative source as policies evolve.
+
+- **ALL external references must be pinned by cryptographic hash.** This
+  includes Docker base images, Go modules, npm packages, GitHub Actions, and
+  anything else fetched from a remote source. Version tags (`@v4`, `@latest`,
+  `:3.21`, etc.) are server-mutable and therefore remote code execution
+  vulnerabilities. The ONLY acceptable way to reference an external dependency
+  is by its content hash (Docker `@sha256:...`, Go module hash in `go.sum`, npm
+  integrity hash in lockfile, GitHub Actions `@<commit-sha>`). No exceptions.
+  This also means never `curl | bash` to install tools like pyenv, nvm, rustup,
+  etc. Instead, download a specific release archive from GitHub, verify its hash
+  (hardcoded in the Dockerfile or script), and only then install. Unverified
+  install scripts are arbitrary remote code execution. This is the single most
+  important rule in this document. Double-check every external reference in
+  every file before committing. There are zero exceptions to this rule.
+
+- Every repo with software must have a root `Makefile` with these targets:
+  `make test`, `make lint`, `make fmt` (writes), `make fmt-check` (read-only),
+  `make check` (prereqs: `test`, `lint`, `fmt-check`), `make docker`, and
+  `make hooks` (installs pre-commit hook). A model Makefile is at
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`.
+
+- Always use Makefile targets (`make fmt`, `make test`, `make lint`, etc.)
+  instead of invoking the underlying tools directly. The Makefile is the single
+  source of truth for how these operations are run.
+
+- The Makefile is authoritative documentation for how the repo is used. Beyond
+  the required targets above, it should have targets for every common operation:
+  running a local development server (`make run`, `make dev`), re-initializing
+  or migrating the database (`make db-reset`, `make migrate`), building
+  artifacts (`make build`), generating code, seeding data, or anything else a
+  developer would do regularly. If someone checks out the repo and types
+  `make<tab>`, they should see every meaningful operation available. A new
+  contributor should be able to understand the entire development workflow by
+  reading the Makefile.
+
+- Every repo should have a `Dockerfile`. All Dockerfiles must run `make check`
+  as a build step so the build fails if the branch is not green. For non-server
+  repos, the Dockerfile should bring up a development environment and run
+  `make check`. For server repos, `make check` should run as an early build
+  stage before the final image is assembled.
+
+- Every repo should have a Gitea Actions workflow (`.gitea/workflows/`) that
+  runs `docker build .` on push. Since the Dockerfile already runs `make check`,
+  a successful build implies all checks pass.
+
+- Use platform-standard formatters: `black` for Python, `prettier` for
+  JS/CSS/Markdown/HTML, `go fmt` for Go. Always use default configuration with
+  two exceptions: four-space indents (except Go), and `proseWrap: always` for
+  Markdown (hard-wrap at 80 columns). Documentation and writing repos (Markdown,
+  HTML, CSS) should also have `.prettierrc` and `.prettierignore`.
+
+- Pre-commit hook: `make check` if local testing is possible, otherwise
+  `make lint && make fmt-check`. The Makefile should provide a `make hooks`
+  target to install the pre-commit hook.
+
+- All repos with software must have tests that run via the platform-standard
+  test framework (`go test`, `pytest`, `jest`/`vitest`, etc.). If no meaningful
+  tests exist yet, add the most minimal test possible — e.g. importing the
+  module under test to verify it compiles/parses. There is no excuse for
+  `make test` to be a no-op.
+
+- `make test` must complete in under 20 seconds. Add a 30-second timeout in the
+  Makefile.
+
+- Docker builds must complete in under 5 minutes.
+
+- `make check` must not modify any files in the repo. Tests may use temporary
+  directories.
+
+- `main` must always pass `make check`, no exceptions.
+
+- Never commit secrets. `.env` files, credentials, API keys, and private keys
+  must be in `.gitignore`. No exceptions.
+
+- `.gitignore` should be comprehensive from the start: OS files (`.DS_Store`),
+  editor files (`.swp`, `*~`), language build artifacts, and `node_modules/`.
+  Fetch the standard `.gitignore` from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when setting up
+  a new repo.
+
+- Never use `git add -A` or `git add .`. Always stage files explicitly by name.
+
+- Never force-push to `main`.
+
+- Make all changes on a feature branch. You can do whatever you want on a
+  feature branch.
+
+- `.golangci.yml` is standardized and must _NEVER_ be modified by an agent, only
+  manually by the user. Fetch from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.golangci.yml`.
+
+- When pinning images or packages by hash, add a comment above the reference
+  with the version and date (YYYY-MM-DD).
+
+- Use `yarn`, not `npm`.
+
+- Write all dates as YYYY-MM-DD (ISO 8601).
+
+- Simple projects should be configured with environment variables.
+
+- Dockerized web services listen on port 8080 by default, overridable with
+  `PORT`.
+
+- `README.md` is the primary documentation. Required sections:
+    - **Description**: First line must include the project name, purpose,
+      category (web server, SPA, CLI tool, etc.), license, and author. Example:
+      "µPaaS is an MIT-licensed Go web application by @sneak that receives
+      git-frontend webhooks and deploys applications via Docker in realtime."
+    - **Getting Started**: Copy-pasteable install/usage code block.
+    - **Rationale**: Why does this exist?
+    - **Design**: How is the program structured?
+    - **TODO**: Update meticulously, even between commits. When planning, put
+      the todo list in the README so a new agent can pick up where the last one
+      left off.
+    - **License**: MIT, GPL, or WTFPL. Ask the user for new projects. Include a
+      `LICENSE` file in the repo root and a License section in the README.
+    - **Author**: [@sneak](https://sneak.berlin).
+
+- First commit of a new repo should contain only `README.md`.
+
+- Go module root: `sneak.berlin/go/<name>`. Always run `go mod tidy` before
+  committing.
+
+- Use SemVer.
+
+- Database migrations live in `internal/db/migrations/` and must be embedded in
+  the binary. Pre-1.0.0: modify existing migrations (no installed base assumed).
+  Post-1.0.0: add new migration files.
+
+- All repos should have an `.editorconfig` enforcing the project's indentation
+  settings.
+
+- Avoid putting files in the repo root unless necessary. Root should contain
+  only project-level config files (`README.md`, `Makefile`, `Dockerfile`,
+  `LICENSE`, `.gitignore`, `.editorconfig`, `REPO_POLICIES.md`, and
+  language-specific config). Everything else goes in a subdirectory. Canonical
+  subdirectory names:
+    - `bin/` — executable scripts and tools
+    - `cmd/` — Go command entrypoints
+    - `configs/` — configuration templates and examples
+    - `deploy/` — deployment manifests (k8s, compose, terraform)
+    - `docs/` — documentation and markdown (README.md stays in root)
+    - `internal/` — Go internal packages
+    - `internal/db/migrations/` — database migrations
+    - `pkg/` — Go library packages
+    - `share/` — systemd units, data files
+    - `static/` — static assets (images, fonts, etc.)
+    - `web/` — web frontend source
+
+- When setting up a new repo, files from the `prompts` repo may be used as
+  templates. Fetch them from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/<path>`.
+
+- New repos must contain at minimum:
+    - `README.md`, `.git`, `.gitignore`, `.editorconfig`
+    - `LICENSE`, `REPO_POLICIES.md` (copy from the `prompts` repo)
+    - `Makefile`
+    - `Dockerfile`, `.dockerignore`
+    - `.gitea/workflows/check.yml`
+    - Go: `go.mod`, `go.sum`, `.golangci.yml`
+    - JS: `package.json`, `yarn.lock`, `.prettierrc`, `.prettierignore`
+    - Python: `pyproject.toml`

build.js

@@ -0,0 +1,46 @@
+const fs = require("fs");
+const path = require("path");
+
+const DIST_CHROME = path.join(__dirname, "dist", "chrome");
+const DIST_FIREFOX = path.join(__dirname, "dist", "firefox");
+
+function ensureDir(dir) {
+    fs.mkdirSync(dir, { recursive: true });
+}
+
+function copyDir(src, dest) {
+    ensureDir(dest);
+    const entries = fs.readdirSync(src, { withFileTypes: true });
+    for (const entry of entries) {
+        const srcPath = path.join(src, entry.name);
+        const destPath = path.join(dest, entry.name);
+        if (entry.isDirectory()) {
+            copyDir(srcPath, destPath);
+        } else {
+            fs.copyFileSync(srcPath, destPath);
+        }
+    }
+}
+
+function build() {
+    console.log("Building AutistMask extension...");
+
+    ensureDir(DIST_CHROME);
+    ensureDir(DIST_FIREFOX);
+
+    copyDir(path.join(__dirname, "src"), path.join(DIST_CHROME, "src"));
+    copyDir(path.join(__dirname, "src"), path.join(DIST_FIREFOX, "src"));
+
+    fs.copyFileSync(
+        path.join(__dirname, "manifest", "chrome.json"),
+        path.join(DIST_CHROME, "manifest.json"),
+    );
+    fs.copyFileSync(
+        path.join(__dirname, "manifest", "firefox.json"),
+        path.join(DIST_FIREFOX, "manifest.json"),
+    );
+
+    console.log("Build complete: dist/chrome/ and dist/firefox/");
+}
+
+build();

manifest/chrome.json

@@ -0,0 +1,20 @@
+{
+    "manifest_version": 3,
+    "name": "AutistMask",
+    "version": "0.1.0",
+    "description": "Minimal Ethereum wallet for Chrome",
+    "permissions": ["storage", "activeTab"],
+    "action": {
+        "default_popup": "src/popup/index.html"
+    },
+    "background": {
+        "service_worker": "src/background/index.js"
+    },
+    "content_scripts": [
+        {
+            "matches": ["<all_urls>"],
+            "js": ["src/content/index.js"],
+            "run_at": "document_start"
+        }
+    ]
+}

manifest/firefox.json

@@ -0,0 +1,25 @@
+{
+    "manifest_version": 2,
+    "name": "AutistMask",
+    "version": "0.1.0",
+    "description": "Minimal Ethereum wallet for Firefox",
+    "permissions": ["storage", "activeTab"],
+    "browser_action": {
+        "default_popup": "src/popup/index.html"
+    },
+    "background": {
+        "scripts": ["src/background/index.js"]
+    },
+    "content_scripts": [
+        {
+            "matches": ["<all_urls>"],
+            "js": ["src/content/index.js"],
+            "run_at": "document_start"
+        }
+    ],
+    "browser_specific_settings": {
+        "gecko": {
+            "id": "autistmask@sneak.berlin"
+        }
+    }
+}

package.json

@@ -0,0 +1,20 @@
+{
+    "name": "autistmask",
+    "version": "0.1.0",
+    "description": "Minimal Ethereum wallet browser extension for Chrome and Firefox",
+    "author": "sneak <sneak@sneak.berlin>",
+    "license": "GPL-3.0",
+    "private": true,
+    "scripts": {
+        "test": "jest --forceExit",
+        "build": "node build.js",
+        "lint": "prettier --check .",
+        "fmt": "prettier --write .",
+        "fmt-check": "prettier --check ."
+    },
+    "devDependencies": {
+        "jest": "^30.2.0",
+        "prettier": "^3.8.1"
+    },
+    "dependencies": {}
+}

src/background/index.js

@@ -0,0 +1,2 @@
+// AutistMask background service worker
+// TODO: wallet management, message routing, provider implementation

src/content/index.js

@@ -0,0 +1,2 @@
+// AutistMask content script
+// TODO: inject window.ethereum provider into page context

src/popup/index.html

@@ -0,0 +1,13 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>AutistMask</title>
+        <link rel="stylesheet" href="styles/main.css" />
+    </head>
+    <body>
+        <div id="app"></div>
+        <script src="index.js"></script>
+    </body>
+</html>

src/popup/index.js

@@ -0,0 +1,2 @@
+// AutistMask popup UI
+// TODO: lock screen, account list, send/receive views

src/popup/styles/main.css

@@ -0,0 +1,18 @@
+* {
+    margin: 0;
+    padding: 0;
+    box-sizing: border-box;
+}
+
+body {
+    width: 360px;
+    min-height: 600px;
+    font-family:
+        -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+    background: #1a1a2e;
+    color: #e0e0e0;
+}
+
+#app {
+    padding: 16px;
+}

src/shared/constants.js

@@ -0,0 +1,22 @@
+const ETHEREUM_MAINNET_CHAIN_ID = "0x1";
+
+const DEFAULT_RPC_URL = "https://eth.llamarpc.com";
+
+const BIP44_ETH_PATH = "m/44'/60'/0'/0";
+
+const ERC20_ABI = [
+    "function name() view returns (string)",
+    "function symbol() view returns (string)",
+    "function decimals() view returns (uint8)",
+    "function balanceOf(address) view returns (uint256)",
+    "function transfer(address to, uint256 amount) returns (bool)",
+    "function allowance(address owner, address spender) view returns (uint256)",
+    "function approve(address spender, uint256 amount) returns (bool)",
+];
+
+module.exports = {
+    ETHEREUM_MAINNET_CHAIN_ID,
+    DEFAULT_RPC_URL,
+    BIP44_ETH_PATH,
+    ERC20_ABI,
+};

tests/constants.test.js

@@ -0,0 +1,29 @@
+const {
+    ETHEREUM_MAINNET_CHAIN_ID,
+    DEFAULT_RPC_URL,
+    BIP44_ETH_PATH,
+    ERC20_ABI,
+} = require("../src/shared/constants");
+
+describe("constants", () => {
+    test("exports expected chain ID", () => {
+        expect(ETHEREUM_MAINNET_CHAIN_ID).toBe("0x1");
+    });
+
+    test("exports a default RPC URL", () => {
+        expect(typeof DEFAULT_RPC_URL).toBe("string");
+        expect(DEFAULT_RPC_URL.startsWith("https://")).toBe(true);
+    });
+
+    test("exports BIP-44 Ethereum derivation path", () => {
+        expect(BIP44_ETH_PATH).toBe("m/44'/60'/0'/0");
+    });
+
+    test("exports ERC-20 ABI with expected functions", () => {
+        expect(Array.isArray(ERC20_ABI)).toBe(true);
+        expect(ERC20_ABI.length).toBeGreaterThan(0);
+        const joined = ERC20_ABI.join(" ");
+        expect(joined).toContain("balanceOf");
+        expect(joined).toContain("transfer");
+    });
+});