Ardent Design

A design system for software that people work in all day. Dense where information rewards it, quiet where focus demands it, and exact everywhere.

Version: 0.3.0
Surfaces: Web · TUI · GUI
Faces: 4
Accents: 4, semantic
Base unit: 4px
Radius: 0
Shadows: 0
Motion: 0ms

Philosophy

8 tenets, in order of precedence

Intentionality over style.

Ardent is neither minimalist nor maximalist. A landing page may be a doorway: quiet, restrained. A dashboard is a workbench: dense, layered. Both are correct when the decision is conscious. The only sin is arbitrariness.

Simple complexity. Ridding the spaces between aesthetics and function.

Rejects

Shadows as depth
Rounded corners as personality
Decorative color
Motion without purpose
Hidden complexity

1Intentionality over styleEvery decision has a reason you can state.
2TransparencyExpose state. Show the system.
3TimelessnessRight in 1978, right in 2045.
4PrecisionEngineered, not decorated.
5Functional densityAs complex as it needs to be. No more, no less.
6Warmth through craftCare is visible in the details.
7Performance is designA slow interface cannot be beautiful.
8Respect for usersCapable adults. Don't infantilize.

Typography

4 faces, one job each

Inter

Structures

Headings, buttons

Luxi Sans

Reads

Body, forms, tables

Old Standard TT

Essays

Quotation, colophon

Go Mono

Signals

Labels, data, code

DisplayInter 700 · 60/66 · −0.025em

Heading 1Inter 700 · 36/40 · −0.025em

Heading 2Inter 700 · 24/30

Heading 3Inter 700 · 20/25

BodyLuxi Sans 400 · 16/22

Body smallLuxi Sans 400 · 14/20

ProseOld Standard 400 · 16/22

LabelGo Mono 700 · 12/17 · +0.05em

CodeGo Mono 400 · 14/20

CaptionGo Mono 400 · 12/17

↑ They do not trade places. Mono never sets a paragraph; serif never sets a table.

Color

Monochrome base · 4 accents

White

#FFFFFF · surface

Black

#000000 · ink, borders

Gray

Structure, ink

100

200

300

400

500

600

700

800

900

950

Emerald

Success, confirm

100

200

300

400

500

600

700

800

900

Goldenrod

Warning, attention

100

200

300

400

500

600

700

800

900

Ocean

Link, information

100

200

300

400

500

600

700

800

900

Red

Error, destructive

100

200

300

400

500

600

700

800

900

↑ Bold step is the signal. Color always means something; it is never wallpaper.

Structure

Hairlines · flat · square

Spacing4px base

14px

28px

312px

416px

624px

832px

1248px

1664px

Bordersstructural

Hairline1px black

Strong2px black

Muted1px gray-200

Constantsnon-negotiable

Radius: 0
Shadow: none
Motion duration: 0ms
Focus ring: 2px black
Reading width: 678px
Spec width: 760px

↑ Hierarchy comes from spacing, scale, weight and rule. Never from elevation.

Components

Flat · hairline · square

Buttons

uppercase · no radius

Form controls

mono label · text value

Service name

Lowercase, hyphenated.

Replicas

Must be between 1 and 64.

Region

Require approval before promote

Status

shape + color + word

RunningDegradedFailedQueuedStopped

Badges

bordered · never filled

v7.3.2PaidPendingOverdueDraft

Meters

capacity · threshold tone

Compute

42%

Storage

78%

Egress

96%

Links

ocean · underlined

See it in use →Back to philosophy ↑

Callouts

code first · one sentence

DEPLOY-OKRevision 7.3.2 is serving all traffic.

QUOTA-80Storage is at 78% of the committed tier.

AUTH-401Deploy key rejected. Rotate it and retry.

MAINT-12Read replicas restart Sunday 02:00Z.

Tabs

inverse marks selection

POST /v1/entries HTTP/1.1
Idempotency-Key: 9f2c-e41a
Content-Type: application/json

{ "account": "1010", "debit": 4820000 }

HTTP/1.1 201 Created
X-Request-Id: req_7Hc2
X-Latency-Ms: 41

{ "id": "JE-4471", "posted": true }

curl -X POST api.example.com/v1/entries \
  -H "Idempotency-Key: 9f2c-e41a" \
  -d '{"account":"1010",
       "debit":4820000}'

Card and key-value

gray-50 · hairline

ledger-writer

Appends balanced entries. Single writer per ledger shard.

Owner: payments-core
Tier: Tier 0
On call: r.castellanos
Last deploy: 2026-11-12 09:14Z

In use

7 exhibits · one component set

A system proves itself under load. These are working screens from the software Ardent is built for: engineering tools and enterprise systems where the data is the interface.

Fleet status

Infrastructure

An on-call engineer needs the whole fleet in one glance and the outlier in the next. Every number is on screen; nothing waits behind a hover.

Requests

18.4K/s↑6.2%

p99 latency

412ms↑162

Error rate

0.04%↓0.01

Services OK

5/8↓1

Servicesprod · us-east-1 · 14:32:07Z

	State	Rev	Ready
ledger-writer	Degraded	7.3.1	5/6	87%	2,210 Mi	412 ms
search-indexer	OK	1.44.0	4/4	52%	3,072 Mi	188 ms
api-gateway	OK	4.18.2	12/12	41%	812 Mi	118 ms
ledger-reader	OK	7.3.1	8/8	36%	1,480 Mi	96 ms
notifier	Draining	3.2.7	2/3	9%	196 Mi	61 ms
auth	OK	2.9.0	6/6	18%	344 Mi	42 ms
edge-cache	OK	5.0.3	16/16	23%	640 Mi	12 ms
billing-cron	Down	0.18.4	0/1	0%	—	—

Deploy log · ledger-writer

$ ardent deploy ledger-writer --rev 7.3.2 --canary 10%
14:31:52Z build    sha256:9f2c…e41a · 31/34 layers cached · 12.4s
14:32:05Z migrate  0043_backfill_entry_group  ok
14:32:07Z canary   1/6 replicas on 7.3.2 · p99 104ms · err 0.00%
14:32:09Z warn     hpa: cpu target 70% exceeded on 2 pods (87%)
14:32:10Z hold     awaiting approval to promote ▌

↑ Sortable columns · tabular numerals · state as shape, color and word

Latency investigation

Observability

One scale, one threshold, one story. Ink carries the measurement; red is spent only on the line that was crossed and the requests that crossed it.

ledger-reader · latency, 24 hpeak 336 ms · 4 h over SLO

p99 msp50 msSLO 250 ms

0100200300400

14:00Z20:00Z02:00Z08:00Z

Distributionms, upper bound

102550751001502505001s1s+

INC-2291resolved · 3 h 34 m

03:41ZBurnp99 budget burning at 6.2× over 1 h window
04:02ZPageSLO breach. p99 274 ms against 250 ms
04:09ZAckAcknowledged by r.castellanos
05:48ZCauseMissing index on entry_group; seq scan under load
07:15ZFixMigration 0042 applied. p99 back under 250 ms

↑ Single y-axis · threshold drawn, not implied · timeline reads top to bottom

General ledger

Finance

Accounting has had a dense, correct visual language for five centuries. Ardent borrows it: right-aligned figures, a double rule over totals, and a balance check that is computed, not asserted.

Cash

4.82M USD↑3.1%

Receivable

1.26M USD↑8.4%

Payable

0.74M USD↓1.7%

Runway

21.4mo→

JournalPeriod 2026-11 · USD · open

Date	Entry	Account	Memo	Debit	Credit
11-09	JE-4471	assets/cash/operating	Northwind inv. 2291 settled	48,200.00
		assets/receivable			48,200.00
11-10	JE-4472	expense/cloud/compute	October compute, accrued	31,480.55
		liabilities/payable			31,480.55
11-10	JE-4473	assets/receivable	Halden annual plan invoiced	96,000.00
		liabilities/deferred-revenue			96,000.00
11-12	JE-4474	liabilities/payable	Vendor run 46	12,750.00
		assets/cash/operating			12,750.00
11-12	JE-4475	liabilities/deferred-revenue	November recognition, 1 of 12	8,000.00
		income/subscriptions			8,000.00
Balanced5 entries · 10 lines				196,430.55	196,430.55

Receivables aging1,260,000.00 USD outstanding

Current	61 inv.	58.9%	742,300.00
1–30 d	24 inv.	25.3%	318,900.00
31–60 d	9 inv.	9.6%	121,400.00
61–90 d	4 inv.	4.2%	52,800.00
90+ d	3 inv.	2.0%	24,600.00

↑ Debits equal credits or the footer says so in red · aging shades darken with risk

Network operations

Aviation

A control room wall, at desk size. Eight measures with twelve hours of history each, the alerts that explain them, and the board they affect.

Flights today

2,847↑12

On time

94.7%↑1.8

Delayed

142↓23

Cancelled

8↑3

Fleet active

312→

In maintenance

24↑3

Load factor

87.3%↑2.1

Pax today

284K↑8%

OPS-12JFK runway 13L/31R closed. AD 2210 cancelled; later JFK departures held.

WX-142DEN flow control. Expect 30–40 min departure delays.

MX-089N742AD returned to service after A-check.

Departures · SFOlocal time · updated 14:02

Flight	To	Sched	Est	Gate	Status
AD 328	ORD Chicago	14:05	14:05	B7	Boarding
AD 1172	DEN Denver	14:20	14:55	B12	Delayed 35m
AD 2210	JFK New York	14:30	—	—	Cancelled
AD 741	SEA Seattle	14:40	14:40	A3	On time
AD 1904	IAH Houston	14:55	14:55	B9	On time
AD 86	EWR Newark	15:10	15:25	B4	Delayed 15m

↑ Arrow gives direction, color gives judgment: fewer delays is ↓ and green

Access review

Enterprise admin

Admin software is where people do careful work quickly. Filters sit above the data they filter, findings are named in the row, and the audit trail is one glance away. Try the filters.

PrincipalsQ4 review · due 2026-11-30

Filter

Role

Findings only

Principal	Role	Scope	2FA	Last seen	Finding
m.okafor	Owner	org/*	Enforced	2 min ago
j.lindqvist	Admin	billing/*	Enforced	1 h ago
svc-deploy	Service	prod/deploy	Key only	14 s ago
r.castellanos	Engineer	prod/read	Enforced	40 min ago
t.nakamura	Engineer	staging/*	Missing	9 d ago	No 2FA
p.oyelaran	Auditor	audit/read	Enforced	5 h ago
a.haddad	Analyst	reports/read	Enforced	41 d ago	Dormant
svc-legacy-etl	Service	warehouse/write	Key only	96 d ago	Dormant

8 of 8 principals

Audit trailtoday · UTC

14:02:11ZGRANTm.okaforr.castellanos → prod/read
13:47:50ZDENYpolicyt.nakamura → prod/deploy (no second factor)
11:20:04ZROTATEsvc-deploydeploy key 7f3a → c91e
09:15:32ZREVOKEj.lindqvistcontractor-17 → billing/read

↑ Live filtering · empty state says what to do · count always visible

Pipeline runs

Data engineering

144 runs in one frame. Success is the quiet default, so the failure at 02:00Z and the two downstream jobs it starved read as a single shape.

Hourly runs, last 24 holdest → newest

ingest.orders

100%4m 12s

ingest.payments

100%6m 48s

normalize.ledger

~××

92%11m 03s

build.fact_revenue

··

100%18m 27s

build.dim_customer

100%2m 40s

export.warehouse

··

100%9m 15s

On time~Late×Failed·Skipped, upstream failedsuccess · median run

↑ Exceptions carry a glyph as well as a color · the cascade is visible, not described

The same fleet, in a terminal

TUI surface

One vocabulary across surfaces. Exhibit A rendered again as a 3270-style operator panel: protected labels recede to gray, values carry the light, accents become the ANSI palette, and the data does not change.

ardent top · 3270 session

 ARDTOP01 ──────────────────── FLEET MONITOR · PROD · US-EAST-1 ───────────── 3 NEED ATTENTION 
 Command ===> █_______________________________________________________________  Scroll ===> CSR
                                                                                               
 Region . . . us-east-1  Env . . . .  prod       Interval . . 5s         Clock . . .  14:32:07Z
 Services . . 8          Ready . . .  53/56      Attention .  3          Sort . . . . state    
                                                                                               
 Cmd Service         State     Rev      Ready  CPU                                 Mem      P99
 ─── ─────────────── ───────── ──────── ─────  ───────────────────────────── ───────── ────────
  _  api-gateway     OK        4.18.2   12/12  ██████████░░░░░░░░░░░░░░  41%     812Mi    118ms
  _  auth            OK        2.9.0      6/6  ████░░░░░░░░░░░░░░░░░░░░  18%     344Mi     42ms
  _  ledger-writer   DEGRADED  7.3.1      5/6  █████████████████████░░░  87%    2210Mi    412ms
  _  ledger-reader   OK        7.3.1      8/8  █████████░░░░░░░░░░░░░░░  36%    1480Mi     96ms
  _  search-indexer  OK        1.44.0     4/4  ████████████░░░░░░░░░░░░  52%    3072Mi    188ms
  _  notifier        DRAINING  3.2.7      2/3  ██░░░░░░░░░░░░░░░░░░░░░░   9%     196Mi     61ms
  _  billing-cron    DOWN      0.18.4     0/1  ░░░░░░░░░░░░░░░░░░░░░░░░   0%         —        —
  _  edge-cache      OK        5.0.3    16/16  ██████░░░░░░░░░░░░░░░░░░  23%     640Mi     12ms
                                                                                               
 Events ─────────────────────────────────────────────────────────────────────────────── 5 of 5 
 14:32:01 ledger-writer   WARN  p99 412ms over the 250ms objective for 6 min                   
 14:31:44 ledger-writer   WARN  replica 6 of 6 not ready: readiness probe timed out            
 14:30:11 notifier        INFO  draining for 3.2.8 rollout, 2 of 3 replicas serving            
 14:28:40 billing-cron    ERR   CrashLoopBackOff · exit 137 OOMKilled · restart 9              
 14:12:05 edge-cache      INFO  scaled 12 → 16 replicas on request rate                        
                                                                                               
  F1=Help  F3=Exit  F5=Refresh  F7=Up  F8=Down  F10=Logs  F12=Cancel

↑ Every line is generated from the fleet data and is exactly 95 cells · dot leaders and F-keys after ISPF