Diamond

Diamond is a small, checked language for writing web applications. Application logic, policies, server-rendered pages, and reactive browser components are written in .dia files. The Rust runtime provides the controlled boundaries to PostgreSQL, HTTP, files, accounts, jobs, and WebSockets.

This repository contains Diamond 0.16.0. It is a working language prototype with two complete reference applications and retained real-interface qualification. Its documented Linux profile is release-qualified; it is not a hosted service or a claim that every production environment is secure.

What you can build

Diamond currently supports:

command-line programs with checked integers, text, records, enums, lists, Option, Result, matching, and bounded utility functions;
server-rendered sites with typed routes, forms, HTML, redirects, local development accounts, SQLite, and authorization policies;
multi-file applications with shared, server, and browser modules;
reactive browser components compiled from Diamond to JavaScript;
PostgreSQL records, relationships, policies, indexed queries, pagination, migrations, and backfills;
shared accounts and sessions, scoped API credentials, private uploads, destination-scoped outbound HTTP, durable jobs, and live events;
policy-bound bare Git repositories, stock Git smart HTTP, bounded repository views, and Google or GitHub login;
repository-defined CI with fenced PostgreSQL scheduling, explicitly isolated native runners and named resource profiles, caches, range-addressable generic artifacts, OCI pulls, environments, and cookie-free static Pages with rollback and custom-domain mappings;
multiple application servers and workers behind an HTTPS proxy, with health checks, draining, encrypted snapshots, and isolated restore.

The best places to see the whole system are:

examples/live-workspace/ — memberships, projects, issues, comments, files, jobs, live updates, and account management;
examples/catalog/ — private drafts, public publishing, JSON APIs, live updates, and deduplicated external notification;
examples/functions/ — every built-in function and callable runtime surface, organized as small examples.

Install Diamond

You need Rust 1.96 or newer.

git clone https://github.com/Corvidae-Coding-Projects/Diamond.git
cd Diamond
cargo install --locked --path .
diamond --version

For work inside this checkout, you can build once and use target/debug/diamond instead:

cargo build --locked
target/debug/diamond --version

Your first Diamond program

Create hello.dia:

fn greeting(name: Text) -> Text:
  "Hello, " + name + "!"

fn main() -> Text:
  greeting("Diamond")

Check it before running it:

diamond check hello.dia
diamond run hello.dia

The result is:

Hello, Diamond!

Diamond uses indentation to define blocks. Function return types are required. Bindings created with let are immutable, and calls are statically checked.

Values, records, and functions

The main scalar types are Int, Bool, Text, nominal Id, Decimal, Timestamp, and Duration. Records, enums, Option, Result, and immutable lists compose those values.

type UserId = Id<"user">

type Person:
  id: UserId
  name: Text<length: 1..80>
  age: Int

enum AccountState:
  Active
  Suspended(reason: Text)

fn describe(state: AccountState) -> Text:
  match state:
    Active => "active"
    Suspended(reason) => "suspended: " + reason

fn label(person: Person) -> Text:
  person.name + " is " + int_text(person.age)

Construct records with named fields and enums with positional payloads:

let person = Person(id: UserId("ada"), name: "Ada", age: 36)
let state = Suspended("review")

Use exhaustive matching for enums, Bool, Option, and Result. Use ? to propagate a Result failure from a compatible function.

fn optional_label(value: Option<Text>) -> Text:
  match value:
    Some(text) => text
    None => "missing"

fn propagate(result: Result<Text, DataError>) -> Result<Text, DataError>:
  let value = result?
  Ok(value)

See the runnable basics.dia and storage_methods.dia examples for complete calls.

Built-in functions

The standard library is intentionally small and bounded:

text: text_slice, text_contains, text_trim, text_replace, join_text;
lists: list_append, list_reverse, list_slice, list_get, len;
decimals: decimal_units, decimal_text, decimal_add, decimal_subtract, decimal_multiply, decimal_divide;
time values: timestamp, duration, time_millis, duration_millis, timestamp_add, timestamp_diff;
conversion: int_text and id_text.

Every function has a runnable example, signature, and notes in the examples/functions catalog. Try all pure examples with:

for file in examples/functions/{basics,text,lists,decimals,time}.dia; do
  diamond run "$file"
done

Records, storage, and policies

A resource binds a record to checked storage operations. Policies are mandatory for protected operations and default to denial when an action is absent.

app NotesApp:
  database SQLite
  provides DbRead<Notes>, DbWrite<Notes>

type NoteId = Id<"note">

type Note:
  id: NoteId
  title: Text
  visible: Bool = true

type NewNote:
  title: Text<length: 1..120>

resource Notes: Note

policy Notes:
  read(note, by principal):
    note.visible
  create(proposed, by principal):
    proposed.visible

fn main() -> Result<NoteId, DataError>:
  let saved = notes.create(NewNote(title: "My first note"))?
  Ok(saved.id)

The source declaration sets the maximum database authority. The host grant is a separate command-line argument:

mkdir -p .diamond
diamond db-init examples/storage.dia --database .diamond/notes.sqlite
diamond run examples/storage.dia --database .diamond/notes.sqlite

Repository methods are create, get, update, delete, and select. The PostgreSQL profile also provides indexed page, cursor, count, sum, and configured join. See examples/functions/storage_methods.dia and the checked relational function project.

Routes, forms, and HTML

Routes declare their visibility, method, typed path, and optional handle:

type NoteId = Id<"note">

type EchoForm:
  message: Text<length: 1..120>

public route GET "/notes/{id:NoteId}" as NotePage:
  html:
    <main><h1>Note {id}</h1></main>

public route POST "/echo":
  let form = request.form<EchoForm>()?
  html:
    <main><p>{form.message}</p></main>

HTML is parsed and checked as part of the program. Interpolated text is escaped, tags and attributes are allowlisted, dynamic internal links use route_url, and forms decode into declared records. The complete helper example is web_helpers.dia:

diamond run examples/functions/web_helpers.dia --listen 127.0.0.1:3000

Open http://127.0.0.1:3000 and stop the development server with Ctrl-C. In another terminal, exercise its typed form route with:

curl --data 'message=Hello from Diamond' http://127.0.0.1:3000/echo

Multi-file and reactive applications

A project manifest assigns each module to shared, server, or browser. Imports share types and pure functions; they do not grant database, network, file, job, or account authority.

schema_version = 1
name = "Counter"
server = "server"
browser = "ui"
component = "Counter"

[modules.shared]
path = "shared.dia"
target = "shared"

[modules.server]
path = "server.dia"
target = "server"
imports = ["shared"]

[modules.ui]
path = "ui.dia"
target = "browser"
imports = ["shared"]

Browser components use typed state and event handlers:

export component Counter:
  state count: Int = 0
  derived label: Text = "Count: " + int_text(count)

  on increment:
    count = count + 1

  html:
    <main>
      <p>{label}</p>
      <button on-click={increment}>Add one</button>
    </main>

Build and serve the included counter:

diamond check examples/foundations/diamond.toml
diamond build examples/foundations/diamond.toml --out .diamond/counter
diamond serve .diamond/counter --listen 127.0.0.1:3000

Open http://127.0.0.1:3000. Build destinations must be new directories; Diamond never silently replaces an existing artifact.

Components also support derived, <when>, keyed <each>, <route>, <use>, forms, bind-value, bind-checked, generated rpc calls, file controls, and typed <watch> subscriptions. See the reactive application guide.

Scaffold a complete application

Diamond embeds two checked starting points:

diamond new my-workspace --template workspace
diamond new my-catalog --template catalog

diamond check my-workspace/diamond.toml
diamond build my-workspace/diamond.toml --out .diamond/my-workspace

The workspace template includes accounts, permissions, records, comments, uploads, outbound HTTP declarations, jobs, and live events. The catalog template shows private authoring and public publishing. Their local READMEs explain every source file and the full browser journey.

Build a Git-backed application

Diamond uses the installed git executable for repository semantics. A Diamond program declares a binding from a Git repository to a policy-protected PostgreSQL resource; it never receives a shell, repository path, environment, or Git configuration access.

provides = ["DbRead<Repositories>", "DbWrite<Repositories>",
            "GitRead<repos>", "GitWrite<repos>",
            "GitReview<repos>", "GitAdmin<repos>"]

[git]
profile = "git-v2"

[git.bindings.repos]
resource = "Repositories"

Server Diamond code can initialize a registered repository and request bounded, typed views:

export fn initialize(repository: Text) -> Result<Text, DataError>:
  host.git_create("repos", repository)

export fn tree(repository: Text, revision: Text, path: Text) -> Result<GitTree, DataError>:
  host.git_query<GitTree>("repos", repository, "tree", revision, path, 100)

export fn protect(repository: Text) -> Result<Text, DataError>:
  host.git_protect("repos", repository, "refs/heads/release/*", "account_admin", false, false, 2, true, true, true, true)

export fn gate(repository: Text, reference: Text, object: Text) -> Result<Text, DataError>:
  host.git_gate("repos", repository, reference, object, 2, true, true, 86400)

export fn merge(repository: Text, source: Text, target: Text, source_object: Text, target_object: Text) -> Result<Text, DataError>:
  host.git_merge("repos", repository, source, target, source_object, target_object)

Available read operations are head, tree, blob, history, and diff. The binding and operation are static so the checker can preserve authority. Repository creation is kept separate from application database writes because Git and PostgreSQL cannot share a transaction.

git_review_gate lets the application review path replace approval and discussion evidence for one exact candidate without receiving Git administration authority. git_integrate performs fast-forward, squash, or merge-commit integration only after both object IDs, the current review gate, and live protected-ref rules match. It records an application-bound receipt; the database finalizer must prove that exact receipt and current target object. git_fork creates a hardened bare clone without hard links or a retained origin remote. These bounded operations expose neither paths nor shell commands to Diamond source.

git_protect accepts an exact branch or tag, or one terminal wildcard such as refs/heads/release/*. Its arguments set the live account role, force-push and deletion policy, approval count, required pipeline and discussion state, signed-commit policy, and secret scanning. Matching rules compose using the strictest requirement. git_gate records short-lived evidence for one exact candidate object; a gate for another commit cannot authorize the push.

The other GitAdmin<binding> operations add and revoke repository-scoped deploy keys and SSH certificate principals, list committed push events, and acknowledge delivery. Every HTTPS and SSH push crosses the same exact-byte pre-receive and post-receive controllers. The receive path validates live identity and policy inside Git's quarantine, commits a private durable event spool, and records the resulting refs in PostgreSQL. Missing or altered hooks, invalid quarantine paths, stale identities, and unavailable policy state fail closed.

Initialize the Git store after the PostgreSQL schema:

mkdir -m 700 /srv/diamond-git /srv/diamond-objects /srv/diamond-delivery /srv/diamond-operations
export DIAMOND_RUNTIME='{"objects":"/srv/diamond-objects","git":{"repos":{"root":"/srv/diamond-git","executable":"/usr/bin/git"}},"delivery":{"builds":{"root":"/srv/diamond-delivery","sandbox":"/usr/bin/systemd-run","limit":"/usr/bin/prlimit"}},"operations":{"control":{"root":"/srv/diamond-operations"}},"http":{}}'
diamond project-init examples/git-browser/diamond.toml --postgres-env DIAMOND_POSTGRES
diamond project-files-init examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME
diamond project-git-init examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME
diamond project-delivery-init examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME
diamond project-ops-init examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME

The delivery-v1 adapter reads a strict .diamond-ci.json from an exact Git commit. Diamond source schedules, cancels, and queries pipelines through host.delivery_schedule, host.delivery_cancel, and host.delivery_query<T>, and performs fixed artifact, environment, Pages, and domain lifecycle operations through host.delivery_command. Native workers alone receive checkout paths and process authority. Run one claim per supervised invocation:

diamond project-delivery-work examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME

diamond project-pages-serve examples/git-browser/diamond.toml \
  --listen 127.0.0.1:3001 --binding builds \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME

The configured sandbox must be the canonical bwrap or systemd-run executable. Bubblewrap uses new user, mount, PID, IPC, UTS, cgroup, and network namespaces. The systemd backend uses a transient chroot-style unit with read-only executable mounts, no network, no host /etc or home view, and memory, task, file-size, and wall-time limits. Isolation failure fails the job. Artifact, OCI blob, and Pages responses stream in 64 KiB chunks; Pages is a separate cookie-free listener. Generic artifacts support HEAD, one byte range, and ETag revalidation. Runner limits come from named, manifest-declared executor profiles; an undeclared profile rejects the pipeline before execution. Pages deployments are immutable and can be rolled back atomically. Custom-host mapping is administrator-only; DNS validation and TLS issuance remain at the deployment edge.

The versioned operations-v1 adapter adds checked OpsRead<binding> and OpsAdmin<binding> capabilities for shared node heartbeats and drain, policy-reauthorized global search, leased search/mirror/GC work, exact-object replica verification, shard/placement generations, object holds, recovery catalogs, shared rate buckets, and redacted audit queries. Initialize its private store with project-ops-init, then run one claim per worker invocation:

diamond project-ops-work examples/git-browser/diamond.toml \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME

Diamond source chooses only fixed selectors and bounded values. It cannot choose SQL, a filesystem path, a Git executable, or a command line. Repository creation records the primary placement automatically. A verified mirror can be queued for promotion; the worker takes a repository-scoped fence, advances the placement generation, and all subsequent smart HTTP, SSH, LFS, and checked repository reads resolve the selected shard. Signed receive claims include the placement generation, so a late request against the previous owner fails closed.

project-backup streams PostgreSQL and every declared shared-object, Git, delivery, and operations root into three private AES256-GnuPG artifacts. Restore requires an empty database and empty canonical roots, verifies all hashes before database import, repairs root-relative Git hook configuration, revokes sessions and API credentials, and validates the restored adapters before returning.

Stock Git clients use the smart HTTP route /_diamond/git/repos/REPOSITORY_ID.git. Public read follows the resource policy. Push and private read use a dia_... credential scoped to the repository and git:repos:read or git:repos:write; the fixed Basic username is diamond. Git LFS batch/basic transfer and owner-bound locking use the standard /_diamond/git/repos/REPOSITORY_ID.git/info/lfs namespace. Objects are streamed through a private content-addressed directory with size and SHA-256 checks.

Users enroll an OpenSSH Ed25519 public key with session.add_ssh_key(label, public_key). session.list_ssh_keys() returns key IDs, SHA-256 fingerprints, labels, dates, and effective revocation state; session.revoke_ssh_key(id) revokes one key. Diamond stores the canonical public key and fingerprint, never a private key.

SSH uses the system OpenSSH daemon. Configure a dedicated Unix account with no ordinary shell access or forwarding. Its AuthorizedKeysCommand should call diamond project-git-authorized-key with the offered %f fingerprint and a fixed launcher path:

diamond project-git-authorized-key /srv/diamond/apps/forge \
  --postgres-env DIAMOND_POSTGRES \
  --fingerprint "$1" \
  --ssh-launcher /usr/local/libexec/diamond-git-ssh

The launcher is a process-owned, non-group-writable executable that loads the deployment's DIAMOND_POSTGRES and DIAMOND_RUNTIME grants, then runs:

exec /usr/local/bin/diamond project-git-ssh /srv/diamond/apps/forge \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME \
  --key-id "$1"

The lookup emits an OpenSSH restrict,command="..." line with an opaque key ID. The forced adapter rechecks the key, account epoch, disablement, repository policy, and protected-ref policy for every connection. It accepts only git-upload-pack 'BINDING/REPOSITORY.git' and git-receive-pack 'BINDING/REPOSITORY.git', plus read-only git-upload-archive; shell commands and extra arguments fail closed.

Deploy keys use the same fingerprint lookup and forced adapter. SSH certificates use an OpenSSH CA plus the output of project-git-authorized-principals as the authorized-principals source. Both identity types are bound to one repository, an expiry or revocation state, and an explicit read-only or write grant. The wrappers, CA configuration, and any environment file are deployment credentials: keep them outside the repository, owned by the Diamond service account, and unwritable by group or other users.

Run project-git-reconcile under supervision to deliver committed spool files to PostgreSQL and rebuild the bounded ref inventory from the fenced source shard. A shard cutover uses an independently synchronized private target root, then compares every registered repository and branch/tag object before the generation changes:

diamond project-git-reconcile /srv/diamond/apps/forge \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME

diamond project-git-promote /srv/diamond/apps/forge \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_NEXT_RUNTIME \
  --binding repos --expected-generation 1

Receives and cutovers use the same PostgreSQL advisory fence. A target that missed a push, has an extra repository or ref, or presents a stale generation is rejected. After a successful promotion the old root's identity is rejected and the new root emits events with the incremented generation.

Projects can also declare Google and GitHub login:

[identity.oauth]
providers = ["google", "github"]
admission = "public"

Admission can be public, restricted, invite, or closed. Restricted deployments can combine email_domains, google_tenants, github_organizations, and explicit identities, with require_all = true when every configured condition must match. Provider client IDs and secret environment-variable names belong in the native runtime JSON, never in .dia source or build artifacts. The complete runnable project and runtime shape are in examples/git-browser/. G2 application and adversarial evidence is recorded in the Diamond Forge application qualification; the lower-level transport evidence remains in the Git and OAuth foundation qualification, and the completed product pass is summarized in the G5 product completion evidence. The six-campaign adversarial replay, concurrent memory observations, isolated restore, fixes, and explicit external gaps are in the G6 bounded release qualification.

Running a connected application requires a local PostgreSQL Unix-socket grant. The workspace also needs a private shared object directory:

mkdir -p .diamond/runtime/objects .diamond/runtime/mail
chmod 700 .diamond/runtime .diamond/runtime/objects .diamond/runtime/mail

export DIAMOND_POSTGRES='host=/run/postgresql dbname=diamond_example user=diamond_example'
export DIAMOND_RUNTIME="{\"objects\":\"$PWD/.diamond/runtime/objects\",\"http\":{}}"

diamond project-init .diamond/my-workspace --postgres-env DIAMOND_POSTGRES
diamond project-files-init .diamond/my-workspace \
  --postgres-env DIAMOND_POSTGRES --runtime-env DIAMOND_RUNTIME
diamond project-admin-add .diamond/my-workspace \
  --postgres-env DIAMOND_POSTGRES --user alice --email [email protected]
diamond serve .diamond/my-workspace --listen 127.0.0.1:3000 \
  --origin http://localhost:3000 --postgres-env DIAMOND_POSTGRES \
  --runtime-env DIAMOND_RUNTIME --identity-mailbox "$PWD/.diamond/runtime/mail"

Create the empty database and least-privilege role before these commands. The administrator command prompts for a password without echo. Open http://localhost:3000 for the development secure-cookie profile. The deployment guide covers two servers, two workers, Caddy, validation, backup, restore, and process supervision.

Command guide

Command	Use
`diamond check PATH`	Parse and type-check a `.dia` file, project manifest, or build.
`diamond run FILE`	Run a single-file `main`, or serve it with `--listen`.
`diamond build PROJECT --out NEW_DIR`	Build checked server/browser artifacts.
`diamond serve PROJECT_OR_BUILD ...`	Serve a project on a loopback address.
`diamond new DIR --template workspace\|catalog`	Create a complete application.
`diamond db-init FILE --database PATH`	Initialize a checked SQLite schema.
`diamond user-add --auth PATH --user NAME`	Add a local development account.
`diamond project-init PROJECT --postgres-env NAME`	Initialize the current PostgreSQL profile.
`diamond project-git-init ...`	Bind and initialize a private native Git store.
`diamond project-delivery-init/work ...`	Initialize delivery state and run one isolated CI job.
`diamond project-ops-init/work ...`	Initialize G4 coordination and run one bounded search, mirror, or GC task.
`diamond project-admin-add ...`	Provision the first connected-app administrator.
`diamond project-work ...`	Run one restricted durable worker.
`diamond project-deploy-check ...`	Validate capabilities and deployment configuration.
`diamond project-status/migrate/backfill/audit ...`	Operate explicit PostgreSQL schema changes.
`diamond project-backup/restore/recover ...`	Operate encrypted quiesced recovery.
`diamond explain CODE`	Explain a diagnostic such as `D204`.
`diamond --help` / `--version`	Show the installed command surface and version.

Run diamond --help for exact arguments. The focused guides explain the larger commands:

Boundaries

Diamond rejects authority that the checked source and host configuration do not both grant. Browser code cannot import server authority. Storage policies are applied before protected data reaches application expressions. External HTTP, files, jobs, account actions, and database operations use closed checked interfaces rather than arbitrary shell, SQL, filesystem, or socket access.

The current qualified profile is Linux x86-64 with Rust 1.96, local Unix-socket PostgreSQL, loopback Diamond servers behind the tested proxy, and operator-provided shared storage. Mixed-version schema operation, public hosting, SMTP, replicated object storage, arbitrary native plugins, shell execution, and general-purpose network access are outside this release. Read the release qualification before deploying it.

Verify the repository

Run the fast build gates and the executable example catalog with:

cargo fmt --all --check
cargo clippy --locked --all-targets --all-features -- -D warnings
cargo test --locked
python3 verification/examples.py

The broader retained qualification is documented in verification/web_ten_results.md, with the Git forge release campaign in verification/git_release_qualification_results.md. Passing a suite is bounded evidence for the tested profile, not proof of total security.

Diamond is published under the MIT license.

Name		Name	Last commit message	Last commit date
.design		.design
deployment		deployment
docs		docs
examples		examples
src		src
verification		verification
.gitignore		.gitignore
CHECKPOINTS.md		CHECKPOINTS.md
Cargo.lock		Cargo.lock
Cargo.toml		Cargo.toml
IMPLEMENTATION_PLAN.md		IMPLEMENTATION_PLAN.md
LICENSE		LICENSE
README.md		README.md
deny.toml		deny.toml
design.md		design.md

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Diamond

What you can build

Install Diamond

Your first Diamond program

Values, records, and functions

Built-in functions

Records, storage, and policies

Routes, forms, and HTML

Multi-file and reactive applications

Scaffold a complete application

Build a Git-backed application

Command guide

Boundaries

Verify the repository

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Diamond

What you can build

Install Diamond

Your first Diamond program

Values, records, and functions

Built-in functions

Records, storage, and policies

Routes, forms, and HTML

Multi-file and reactive applications

Scaffold a complete application

Build a Git-backed application

Command guide

Boundaries

Verify the repository

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