Mark Headd
@mheadd.bsky.social
I post about #GovernmentTech #CivicTech #ServiceDelivery #OpenData. Personal account, views expressed are all mine.
Love this new project for spec-driven development (SDD). Not only because it makes working with #AI tools more logical and efficient, but because it enables developers and teams to treat the specification as the source of truth on system behavior, not the implemented code. github.com/Fission-AI/O...
GitHub - Fission-AI/OpenSpec: Spec-driven development (SDD) for AI coding assistants.
Spec-driven development (SDD) for AI coding assistants. - Fission-AI/OpenSpec
github.com
January 6, 2026 at 3:25 PM
Love this new project for spec-driven development (SDD). Not only because it makes working with #AI tools more logical and efficient, but because it enables developers and teams to treat the specification as the source of truth on system behavior, not the implemented code. github.com/Fission-AI/O...
Reposted by Mark Headd
Here's my enormous round-up of everything we learned about LLMs in 2025 - the third in my annual series of reviews of the past twelve months
simonwillison.net/2025/Dec/31/...
This year it's divided into 26 sections! This is the table of contents:
simonwillison.net/2025/Dec/31/...
This year it's divided into 26 sections! This is the table of contents:
December 31, 2025 at 11:54 PM
Here's my enormous round-up of everything we learned about LLMs in 2025 - the third in my annual series of reviews of the past twelve months
simonwillison.net/2025/Dec/31/...
This year it's divided into 26 sections! This is the table of contents:
simonwillison.net/2025/Dec/31/...
This year it's divided into 26 sections! This is the table of contents:
Reposted by Mark Headd
I wrote about 10 things Mamdani's incoming administration can do to transform how the city delivers to ensure his agenda becomes a reality.
open.substack.com/pub/publicse...
open.substack.com/pub/publicse...
What it will take to deliver for New Yorkers: transform how the city delivers
A special edition. Your source of tech and innovation jobs in government.
open.substack.com
December 20, 2025 at 10:04 PM
I wrote about 10 things Mamdani's incoming administration can do to transform how the city delivers to ensure his agenda becomes a reality.
open.substack.com/pub/publicse...
open.substack.com/pub/publicse...
Do you want to learn how to modernize legacy technology systems with simple hands-on training? Well, Happy Holidays, because I have a gift for you. 🎄🕎 1/4
December 27, 2025 at 4:21 PM
Do you want to learn how to modernize legacy technology systems with simple hands-on training? Well, Happy Holidays, because I have a gift for you. 🎄🕎 1/4
I ❤️ Philly. #CivicHacking capitol of the world. www.youtube.com/watch?v=kD6N...
South Philly street artist helps create signs displaying SEPTA bus arrival times
YouTube video by FOX 29 Philadelphia
www.youtube.com
December 27, 2025 at 12:51 PM
I ❤️ Philly. #CivicHacking capitol of the world. www.youtube.com/watch?v=kD6N...
Reposted by Mark Headd
Fragments: Illustrated guide to mainframe modernization, what the second value of code reviews means for LLMs, LLMs write and then port an HTML parser
martinfowler.com/fragments/20...
martinfowler.com/fragments/20...
Fragments: December 16
fragments 16 Dec 2025
martinfowler.com
December 16, 2025 at 3:51 PM
Fragments: Illustrated guide to mainframe modernization, what the second value of code reviews means for LLMs, LLMs write and then port an HTML parser
martinfowler.com/fragments/20...
martinfowler.com/fragments/20...
Reposted by Mark Headd
OpenAI aren't talking about it yet, but it turns out they've adopted Anthropic's brilliant "skills" mechanism in a big way
Skills are now live in both ChatGPT and their Codex CLI tool, I wrote up some detailed notes on how they work so far here: simonwillison.net/2025/Dec/12/...
Skills are now live in both ChatGPT and their Codex CLI tool, I wrote up some detailed notes on how they work so far here: simonwillison.net/2025/Dec/12/...
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI
One of the things that most excited me about Anthropic’s new Skills mechanism back in October is how easy it looked for other platforms to implement. A skill is just …
simonwillison.net
December 12, 2025 at 11:32 PM
OpenAI aren't talking about it yet, but it turns out they've adopted Anthropic's brilliant "skills" mechanism in a big way
Skills are now live in both ChatGPT and their Codex CLI tool, I wrote up some detailed notes on how they work so far here: simonwillison.net/2025/Dec/12/...
Skills are now live in both ChatGPT and their Codex CLI tool, I wrote up some detailed notes on how they work so far here: simonwillison.net/2025/Dec/12/...
Most legacy government systems exist in a state of profound documentation poverty. The biggest potential value of using #AI to improve legacy systems will come not from transforming old software code into new software code but from compiling the knowledge of how a system actually works.
spec-ops.ai
spec-ops.ai
SpecOps: Specification-Driven Legacy Modernization
Specifications over code. Preserve institutional knowledge, verify behavior, and generate modern systems with AI.
spec-ops.ai
December 10, 2025 at 6:31 PM
Most legacy government systems exist in a state of profound documentation poverty. The biggest potential value of using #AI to improve legacy systems will come not from transforming old software code into new software code but from compiling the knowledge of how a system actually works.
spec-ops.ai
spec-ops.ai
Reposted by Mark Headd
If you're interested in spec-driven development with #AI coding assistants, here is a brand new GitHub action just published to the marketplace.
github.com/marketplace/...
github.com/marketplace/...
Spec Ops Action - GitHub Marketplace
Automatically create GitHub issues when specification files change. Supports spec-first workflows
github.com
December 7, 2025 at 5:24 PM
If you're interested in spec-driven development with #AI coding assistants, here is a brand new GitHub action just published to the marketplace.
github.com/marketplace/...
github.com/marketplace/...
If you're interested in spec-driven development with #AI coding assistants, here is a brand new GitHub action just published to the marketplace.
github.com/marketplace/...
github.com/marketplace/...
Spec Ops Action - GitHub Marketplace
Automatically create GitHub issues when specification files change. Supports spec-first workflows
github.com
December 7, 2025 at 5:24 PM
If you're interested in spec-driven development with #AI coding assistants, here is a brand new GitHub action just published to the marketplace.
github.com/marketplace/...
github.com/marketplace/...
This is worth your time to read. One thing some of the language in here reminds me of strongly is the idea of just-in-time interfaces, enabled by new AI tools. signalpath.substack.com/p/just-in-ti...
December 5, 2025 at 4:22 PM
This is worth your time to read. One thing some of the language in here reminds me of strongly is the idea of just-in-time interfaces, enabled by new AI tools. signalpath.substack.com/p/just-in-ti...
Reposted by Mark Headd
Let's build hyper-personalized AI-powered software that avoids the attention hijacking anti-patterns that defined so much of the last decade of software design - here's our manifesto with principles on how we can do that - more thoughts on my blog: simonwillison.net/2025/Dec/5/r...
December 5, 2025 at 4:13 PM
Let's build hyper-personalized AI-powered software that avoids the attention hijacking anti-patterns that defined so much of the last decade of software design - here's our manifesto with principles on how we can do that - more thoughts on my blog: simonwillison.net/2025/Dec/5/r...
Results of an experiment I ran recently to test out a new approach to legacy system modernization. I'm really excited by the results, and more convinced than ever that this approach has tremendous potential for governments struggling with outdated systems.
civic.io/2025/12/04/p...
#CivicTech #AI
civic.io/2025/12/04/p...
#CivicTech #AI
Proving Out a New Approach to Legacy System Modernization
Government legacy systems hold decades of institutional knowledge that disappears when we focus only on translating old code to new code. I’ve been developing SpecOps—a methodology that uses …
civic.io
December 4, 2025 at 4:56 PM
Results of an experiment I ran recently to test out a new approach to legacy system modernization. I'm really excited by the results, and more convinced than ever that this approach has tremendous potential for governments struggling with outdated systems.
civic.io/2025/12/04/p...
#CivicTech #AI
civic.io/2025/12/04/p...
#CivicTech #AI
This is the most 2025 headline of all time.
Imagine trying to explain this to someone living 10 years ago. www.wired.com/story/poems-...
Imagine trying to explain this to someone living 10 years ago. www.wired.com/story/poems-...
December 3, 2025 at 7:53 PM
This is the most 2025 headline of all time.
Imagine trying to explain this to someone living 10 years ago. www.wired.com/story/poems-...
Imagine trying to explain this to someone living 10 years ago. www.wired.com/story/poems-...
Reposted by Mark Headd
hi friends, I’m so thrilled @publicgood.tech is on BlueSky! I've been a board member since 2021 & I care deeply about this org: the only one dedicated to supporting the people who do the very hard work of civic tech
Heads-up: I’m asking for donations give.socialgoodfund.org/t4pg-fund?re...
Heads-up: I’m asking for donations give.socialgoodfund.org/t4pg-fund?re...
November 22, 2025 at 5:58 PM
hi friends, I’m so thrilled @publicgood.tech is on BlueSky! I've been a board member since 2021 & I care deeply about this org: the only one dedicated to supporting the people who do the very hard work of civic tech
Heads-up: I’m asking for donations give.socialgoodfund.org/t4pg-fund?re...
Heads-up: I’m asking for donations give.socialgoodfund.org/t4pg-fund?re...
Reposted by Mark Headd
There is such a thirst in some progressive centrist circles that they will look at the Trump administration as a model to get things done. I think its worth addressing the argument. This is from Mark Dunkelman, author of the widely praised "Why Nothing Works."
www.nytimes.com/2025/12/03/o...
www.nytimes.com/2025/12/03/o...
Opinion | What the Left Could Learn From Trump’s Brutal Efficiency
www.nytimes.com
December 3, 2025 at 1:48 PM
There is such a thirst in some progressive centrist circles that they will look at the Trump administration as a model to get things done. I think its worth addressing the argument. This is from Mark Dunkelman, author of the widely praised "Why Nothing Works."
www.nytimes.com/2025/12/03/o...
www.nytimes.com/2025/12/03/o...
A thing I have come to appreciate about AI coding assistants is their high level of git-literacy. Git is notoriously user unfriendly and - frankly - scary at times. If you've ever felt a tinge of fear when using a "detached HEAD" or done a "git reset --hard" you'll come to appreciate their abilities
December 3, 2025 at 3:07 PM
A thing I have come to appreciate about AI coding assistants is their high level of git-literacy. Git is notoriously user unfriendly and - frankly - scary at times. If you've ever felt a tinge of fear when using a "detached HEAD" or done a "git reset --hard" you'll come to appreciate their abilities
Reposted by Mark Headd
🎁 Today is Giving Tuesday—a day to invest in the future we want to see.
Your support = more mentorship, more convenings, more impact.
give.socialgoodfund.org/t4pg-fund
#GivingTuesday #CivicTech #PublicGood
Your support = more mentorship, more convenings, more impact.
give.socialgoodfund.org/t4pg-fund
#GivingTuesday #CivicTech #PublicGood
Support the Future of Public Interest Technology
Please support us by making a contribution!
give.socialgoodfund.org
December 2, 2025 at 3:45 PM
🎁 Today is Giving Tuesday—a day to invest in the future we want to see.
Your support = more mentorship, more convenings, more impact.
give.socialgoodfund.org/t4pg-fund
#GivingTuesday #CivicTech #PublicGood
Your support = more mentorship, more convenings, more impact.
give.socialgoodfund.org/t4pg-fund
#GivingTuesday #CivicTech #PublicGood
Reposted by Mark Headd
At the risk of starting the flame war to end all flame wars...
Modern LLMs (GPT-5.1, Claude 4.5, Gemini 3) produce excellent code and can be a significant productivity boost to software engineers who take the time to learn how to effectively apply them - especially if used with coding agent tools
Modern LLMs (GPT-5.1, Claude 4.5, Gemini 3) produce excellent code and can be a significant productivity boost to software engineers who take the time to learn how to effectively apply them - especially if used with coding agent tools
November 27, 2025 at 7:55 PM
At the risk of starting the flame war to end all flame wars...
Modern LLMs (GPT-5.1, Claude 4.5, Gemini 3) produce excellent code and can be a significant productivity boost to software engineers who take the time to learn how to effectively apply them - especially if used with coding agent tools
Modern LLMs (GPT-5.1, Claude 4.5, Gemini 3) produce excellent code and can be a significant productivity boost to software engineers who take the time to learn how to effectively apply them - especially if used with coding agent tools
Government legacy systems hold decades of institutional knowledge that disappears when we focus only on translating old code to new code. I've been developing SpecOps: a methodology that uses AI to extract that knowledge into plain-language specifications that policy experts can actually verify. 1/2
November 30, 2025 at 8:07 PM
Government legacy systems hold decades of institutional knowledge that disappears when we focus only on translating old code to new code. I've been developing SpecOps: a methodology that uses AI to extract that knowledge into plain-language specifications that policy experts can actually verify. 1/2
I love this line. It's so true it hurts.
"Few IT projects are displays of rational decision-making from which AI can or should learn. "
spectrum.ieee.org/it-managemen...
"Few IT projects are displays of rational decision-making from which AI can or should learn. "
spectrum.ieee.org/it-managemen...
November 29, 2025 at 3:33 PM
I love this line. It's so true it hurts.
"Few IT projects are displays of rational decision-making from which AI can or should learn. "
spectrum.ieee.org/it-managemen...
"Few IT projects are displays of rational decision-making from which AI can or should learn. "
spectrum.ieee.org/it-managemen...
Reposted by Mark Headd
Frontend is failing. 75% of devices with browsers are smartphones, but not even half of sites pass Core Web Vitals on them. Why not? Too much JavaScript, added to indulge SPA fantasies the data is falsifying in real time:
infrequently.org/2025/11/perf...
infrequently.org/2025/11/perf...
The Performance Inequality Gap, 2026 - Infrequently Noted
Embedded in this year's network and device estimates is hopeful news about the trajectory of devices and networks. It has never been easier to deliver pages quickly, but we are not collectively…
infrequently.org
November 25, 2025 at 5:23 PM
Frontend is failing. 75% of devices with browsers are smartphones, but not even half of sites pass Core Web Vitals on them. Why not? Too much JavaScript, added to indulge SPA fantasies the data is falsifying in real time:
infrequently.org/2025/11/perf...
infrequently.org/2025/11/perf...
Reposted by Mark Headd
As an example of how we are building on top of Gemini 3, AI Mode in Search now uses Gemini 3 to enable new generative UI experiences, all generated completely on the fly based on your query. Here’s how you might use this to learn a complex topic like how RNA polymerase works.
November 19, 2025 at 2:58 AM
As an example of how we are building on top of Gemini 3, AI Mode in Search now uses Gemini 3 to enable new generative UI experiences, all generated completely on the fly based on your query. Here’s how you might use this to learn a complex topic like how RNA polymerase works.
I've been thinking a lot lately about how legacy system modernization gets done in government, and about how new AI tools and development approaches can dramatically change the way we've approached this challenge in the past. spec-ops.ai
SpecOps: Specification-Driven Legacy Modernization
Specifications over code. Preserve institutional knowledge, verify behavior, and generate modern systems with AI.
spec-ops.ai
November 13, 2025 at 8:42 PM
I've been thinking a lot lately about how legacy system modernization gets done in government, and about how new AI tools and development approaches can dramatically change the way we've approached this challenge in the past. spec-ops.ai
Reposted by Mark Headd
I wrote about what @zohrankmamdani.bsky.social’s administration can do starting Day 1 to make sure NYC’s civil service and hiring system can help deliver for New Yorkers. #PublicSectorJobBoard
open.substack.com/pub/publicse...
open.substack.com/pub/publicse...
What it will take to deliver for New Yorkers: modernize the civil service and hiring process
A special edition. Your source of tech and innovation jobs in government.
open.substack.com
November 12, 2025 at 6:30 PM
I wrote about what @zohrankmamdani.bsky.social’s administration can do starting Day 1 to make sure NYC’s civil service and hiring system can help deliver for New Yorkers. #PublicSectorJobBoard
open.substack.com/pub/publicse...
open.substack.com/pub/publicse...