Debuglet

Debuglet runs small WebAssembly programs for network measurements. A dispatcher accepts jobs and stores results; executors run the programs with time and bandwidth budgets. This repository includes the dbl CLI, a native Go client SDK, a WASI guest SDK, and sample measurements.

The local alpha runs on Linux amd64. The complete package needs no Go compiler, wallet, SCION service, root privileges, or hand-written daemon configuration.

Install

Build the release candidate from the main branch on Linux amd64 with Go 1.25.11, Git, Make, Bash, GNU tar and coreutils (sha256sum). Use a clean checkout; the package records its exact source revision and uses committed eBPF objects, so building it needs no kernel privileges or eBPF compiler.

git clone --branch main https://github.com/netsec-ethz/debuglet.git
cd debuglet
make ci-build
make ci-package
(
  set -eu
  cd .cache/ci/packages
  sha256sum --check SHA256SUMS
  set -- debuglet-v*-linux-amd64.tar.gz
  [ "$#" -eq 1 ]
  [ -f "$1" ]
  version=${1#debuglet-}; version=${version%-linux-amd64.tar.gz}
  sh ./install.sh --archive "$1" --checksums ./SHA256SUMS \
    --version "$version" --prefix "$HOME/.local"
)

The CLI is installed under $HOME/.local/bin, with its package under $HOME/.local/lib/debuglet. Copying the three package files to another Linux amd64 machine supports installation there without Go or a source checkout. The installation guide covers offline installation and version-pinned release downloads. The v0.2.0-rc.1 package is the first release candidate for this workflow; v0.1.0 predates it.

export PATH="$HOME/.local/bin:$PATH"
dbl demo

demo starts a temporary local dispatcher and executor, runs a real WASM/TCP measurement, checks the result, and cleans up. No existing service is required. Successful human output begins with Debuglet VERSION completed locally: and ends with Cleanup: complete; JSON output also records RunStateExited.

Start roles independently

Start a dispatcher in one terminal:

dbl dispatcher up

It creates its configuration and database and prints a dispatcher URL. In a second terminal, start an executor using that URL:

dbl executor up --dispatcher http://127.0.0.1:9000

The executor discovers the connection details, registers, and reports when it is ready. In a third terminal, connect the client and send a job:

dbl connect http://127.0.0.1:9000 --name local
dbl dispatcher list
dbl executor list
dbl run --sample hello --wait
dbl logs <id-from-the-run-receipt>

The client saves the connection. --sample hello needs no compiler or wallet. When exactly one executor is ready, run selects it; with several, use --executor ID. Press Ctrl-C to stop a foreground role. Same-package restarts retain its identity, completed results and output, but do not resume interrupted measurements.

See the CLI guide for multiple roles, state paths, validation, services and drain operations. The architecture guide shows how submission, execution, output and completion travel through the system.

Credentials

No login is needed for the local roles above. The configuration they generate sets server.local_development, the documented profile in which a dispatcher whose listeners are on loopback, with TLS and payments disabled, serves a request that presents no credential at all as its own local operator. Every other configuration — a managed service, and every deployment example — authenticates each request that is not public and authorizes it against the account that owns the object. There, register once and obtain a session:

dbl connect http://127.0.0.1:9000 --name managed
dbl --dispatcher managed login --register researcher

The command writes the account key and recovery code to owner-only files beside the client configuration. A session lasts 12 hours. Log in again with the path printed during registration, for example:

dbl --dispatcher managed login \
  --account-key-file ~/.config/debuglet/account-key-managed.txt

dbl logout revokes the session. If the account key is lost, the recovery code can replace both credentials through POST /auth/recover or pkg/client.Recover; the CLI does not yet expose recovery. The CLI guide covers credential locations and the HTTP API guide covers recovery and authorization.

Write a measurement or application

To build a Go measurement, install Go 1.25.11, clone this repository and run:

make wasm SAMPLE_DIR=local/wasm_samples/go/hello-local
dbl run --wasm local/wasm_samples/go/hello-local/debuglet.wasm --wait

Replace the sample with your own guest. Go guests compile for GOOS=wasip1 GOARCH=wasm and import github.com/netsec-ethz/debuglet/pkg/debuglet when they need Debuglet's network operations. See the WASM samples.

For an application that submits measurements and reads results, use the native pkg/client SDK. With a dispatcher and executor still running, this complete example submits the guest you just built and prints its output:

go run -mod=readonly ./examples/client --wasm local/wasm_samples/go/hello-local/debuglet.wasm

The CLI guide covers submission, results, logs, and cancellation.

For a client in another language, the dispatcher publishes its HTTP wire contract as an OpenAPI document at api/openapi.yaml, and serves the one it was built from at GET /openapi.yaml. GET /version reports the three identities of a running dispatcher separately: the HTTP contract version it serves, the binary it was built from, and the executor control protocol it speaks. The HTTP API guide states how a client selects a contract version and what may change without a new major version.

Development

On Linux amd64 with Go 1.25.11, Git, Make, Bash, GNU tar and coreutils (plus Python 3 for the test and installed-check targets):

make ci-test
make ci-vet
make ci-build
make ci-package
make ci-local

Package builds require a clean, committed checkout and use the committed generated eBPF objects. Output is under .cache/ci/packages/. The CI workflow defines checks for tests, build, packaging, the installed demo, combined and separate local roles, SDK use, compatibility, and kernel loading. GitHub Actions runs them on fresh GitHub-hosted Ubuntu 24.04 VMs; see CI setup.

See CONTRIBUTING.md for code generation and development details. The architecture guide maps the packages to the running system, including both control paths and where a given change belongs.

Current limits

• This alpha uses trusted local Linux processes and TEST payment bookkeeping. Wallet and monetary operation are not validated.
• The persistent environment retains stored results; it does not establish durable result delivery or recover unknown/interrupted execution outcomes.
• Cancellation acknowledges a request; it does not certify remote termination.
• The HTTP API authenticates a session and authorizes every operation that is not public against the owning account or the operator role. What is still open: nothing rate-limits account registration or login attempts, registration is open to anyone who can reach the port, the operator role can be granted only on the dispatcher host, and an executor's identity is bound to an enrolled certificate only where tls.require_client_cert is set.
• A guest is not isolated from the executor process: it runs under the wazero interpreter with no memory ceiling beyond the module's own, no CPU accounting and no namespace confinement. A destination that did not ask to be measured is protected only by the operator's denial list and the run's declared destinations. Keep the alpha in a trusted local environment.
• SCION and remote testbed operation are outside this walkthrough. ETH testbed compatibility and deployment are unconfirmed.
• Checksums are not release signatures. This release candidate has no supported upgrade path: a state directory stays with the package version that created it, and moving to another version means a new state directory.

The threat model states which actors and trust boundaries the supported profile assumes, what it promises and what it does not, and why a session token, a packet tag, a live control lease or completed local cleanup is not proof of identity, remote completion or non-repudiation.

SECURITY.md states the supported versions and how to arrange private vulnerability reporting.

License

Apache License 2.0. Existing copyright notices are retained.