ArkType
@arktype.io
TypeScript's 1:1 validator, optimized from editor to runtime ⛵
⭐http://github.com/arktypeio/arktype
👋http://arktype.io/discord
⭐http://github.com/arktypeio/arktype
👋http://arktype.io/discord
all you need to "learn" ArkType syntax:
1️⃣ start with a typescript keyword
2️⃣ .autocomplete to discover constraints
3️⃣ compose if needed with &, |, etc.
1️⃣ start with a typescript keyword
2️⃣ .autocomplete to discover constraints
3️⃣ compose if needed with &, |, etc.
December 22, 2025 at 7:06 PM
all you need to "learn" ArkType syntax:
1️⃣ start with a typescript keyword
2️⃣ .autocomplete to discover constraints
3️⃣ compose if needed with &, |, etc.
1️⃣ start with a typescript keyword
2️⃣ .autocomplete to discover constraints
3️⃣ compose if needed with &, |, etc.
tools are just introspectable functions...
what if you could define them like this?🤔
what if you could define them like this?🤔
December 18, 2025 at 5:19 PM
tools are just introspectable functions...
what if you could define them like this?🤔
what if you could define them like this?🤔
wish TS had rust-style pattern matching?
(it already does)🪄
(it already does)🪄
December 17, 2025 at 5:34 PM
wish TS had rust-style pattern matching?
(it already does)🪄
(it already does)🪄
🚨Standard JSON Schema v1 just dropped🚨
🟢libraries can now accept ArkType wherever they need JSON Schema
🟢100% type-safe with inference built-in
🟢day one support from AI SDK
🟢TanStack AI and MCP SDK support imminent
🟢libraries can now accept ArkType wherever they need JSON Schema
🟢100% type-safe with inference built-in
🟢day one support from AI SDK
🟢TanStack AI and MCP SDK support imminent
December 16, 2025 at 7:56 PM
🚨Standard JSON Schema v1 just dropped🚨
🟢libraries can now accept ArkType wherever they need JSON Schema
🟢100% type-safe with inference built-in
🟢day one support from AI SDK
🟢TanStack AI and MCP SDK support imminent
🟢libraries can now accept ArkType wherever they need JSON Schema
🟢100% type-safe with inference built-in
🟢day one support from AI SDK
🟢TanStack AI and MCP SDK support imminent
Reposted by ArkType
🎉Announcing Standard JSON Schema🎉
The next spec in the Standard Schema family is here to bring library-agnostic JSON Schema to TS.
Let's make sure everyone sees it🔁
The next spec in the Standard Schema family is here to bring library-agnostic JSON Schema to TS.
Let's make sure everyone sees it🔁
December 16, 2025 at 7:08 PM
🎉Announcing Standard JSON Schema🎉
The next spec in the Standard Schema family is here to bring library-agnostic JSON Schema to TS.
Let's make sure everyone sees it🔁
The next spec in the Standard Schema family is here to bring library-agnostic JSON Schema to TS.
Let's make sure everyone sees it🔁
Reposted by ArkType
Introducing ✨ Standard JSON Schema ✨
It's a sister spec to Standard Schema that provides a common interface for any entity that can be converted to JSON Schema
It's a sister spec to Standard Schema that provides a common interface for any entity that can be converted to JSON Schema
December 15, 2025 at 11:28 PM
Introducing ✨ Standard JSON Schema ✨
It's a sister spec to Standard Schema that provides a common interface for any entity that can be converted to JSON Schema
It's a sister spec to Standard Schema that provides a common interface for any entity that can be converted to JSON Schema
mission accomplished @mattpocock.com
December 11, 2025 at 6:10 PM
mission accomplished @mattpocock.com
BETRAYAL
sounds fake but I'm starting a company with my nemesis Colin P. Zod
and our first hire is @AndaristRake
and our first product is now in beta
and our first hire is @AndaristRake
and our first product is now in beta
December 10, 2025 at 5:40 PM
BETRAYAL
"bUt StRiNgS aReN'T tYpE sAfE"
December 9, 2025 at 6:25 PM
"bUt StRiNgS aReN'T tYpE sAfE"
95% of ArkType syntax is just TypeScript.
The other 5% are extensions like this that are...
✅composable
✅consistent across data types
✅100% safe with helpful type-level error messages
The other 5% are extensions like this that are...
✅composable
✅consistent across data types
✅100% safe with helpful type-level error messages
December 8, 2025 at 6:57 PM
95% of ArkType syntax is just TypeScript.
The other 5% are extensions like this that are...
✅composable
✅consistent across data types
✅100% safe with helpful type-level error messages
The other 5% are extensions like this that are...
✅composable
✅consistent across data types
✅100% safe with helpful type-level error messages
once you go type("string") you never go z.back()
December 5, 2025 at 5:22 PM
once you go type("string") you never go z.back()
Difficulty of Parsing Regex with TypeScript Types
------------------------------------------------------------
group associativity ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
everything else ▒▒
------------------------------------------------------------
group associativity ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
everything else ▒▒
December 2, 2025 at 5:51 PM
Difficulty of Parsing Regex with TypeScript Types
------------------------------------------------------------
group associativity ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
everything else ▒▒
------------------------------------------------------------
group associativity ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
everything else ▒▒
In the next version of ArkType, any Standard Schema is a valid definition.
Zod migration is about to get a whole lot easier🚀
Zod migration is about to get a whole lot easier🚀
December 1, 2025 at 6:39 PM
In the next version of ArkType, any Standard Schema is a valid definition.
Zod migration is about to get a whole lot easier🚀
Zod migration is about to get a whole lot easier🚀
fastest, cleanest tuple validation around
November 26, 2025 at 3:53 PM
fastest, cleanest tuple validation around
RIP z.shark()
long live sharktype
long live sharktype
November 24, 2025 at 5:53 PM
RIP z.shark()
long live sharktype
long live sharktype
friends don't let friends have unsafe regex
November 20, 2025 at 5:53 PM
friends don't let friends have unsafe regex
coming in ArkType 2.2...
e(x)ec mode for regex literals🧑🍳
e(x)ec mode for regex literals🧑🍳
November 19, 2025 at 6:03 PM
coming in ArkType 2.2...
e(x)ec mode for regex literals🧑🍳
e(x)ec mode for regex literals🧑🍳
📈arkregex just hit 100k installs/week📈
if you're still using untyped RegExp() you may as well just write raw .js
if you're still using untyped RegExp() you may as well just write raw .js
November 18, 2025 at 5:24 PM
📈arkregex just hit 100k installs/week📈
if you're still using untyped RegExp() you may as well just write raw .js
if you're still using untyped RegExp() you may as well just write raw .js
string validation has never been this easy
arktype🤝arkregex
arktype🤝arkregex
November 13, 2025 at 5:31 PM
string validation has never been this easy
arktype🤝arkregex
arktype🤝arkregex
problem:
your RegExp is beyond human comprehension
solution:
pnpm i arkregex
your RegExp is beyond human comprehension
solution:
pnpm i arkregex
November 12, 2025 at 6:13 PM
problem:
your RegExp is beyond human comprehension
solution:
pnpm i arkregex
your RegExp is beyond human comprehension
solution:
pnpm i arkregex
I'll take "meticulously typed regex features you probably didn't know existed" for $500
November 10, 2025 at 7:02 PM
I'll take "meticulously typed regex features you probably didn't know existed" for $500
in the latest version of arktype:
regex properties and index signatures from arkregex🔒
regex properties and index signatures from arkregex🔒
November 7, 2025 at 3:26 PM
in the latest version of arktype:
regex properties and index signatures from arkregex🔒
regex properties and index signatures from arkregex🔒
imagine using untyped regex in 2025
November 6, 2025 at 1:42 PM
imagine using untyped regex in 2025
arkregex is ridiculously optimized.
even expressions like this are inferred instantly.
but what about the most extreme cases?🧵
even expressions like this are inferred instantly.
but what about the most extreme cases?🧵
November 5, 2025 at 2:26 PM
arkregex is ridiculously optimized.
even expressions like this are inferred instantly.
but what about the most extreme cases?🧵
even expressions like this are inferred instantly.
but what about the most extreme cases?🧵
new RegExp():
❌types
😴tired
arkregex:
✅types
🫨wired
❌types
😴tired
arkregex:
✅types
🫨wired
November 3, 2025 at 5:44 PM
new RegExp():
❌types
😴tired
arkregex:
✅types
🫨wired
❌types
😴tired
arkregex:
✅types
🫨wired