Close tech stack
Close builds mostly with Python, TypeScript, JavaScript, Rust. Its stack also includes AWS, GitHub, ElasticSearch, PostgreSQL. Python is named in 8 of the 11 job postings Close published in the last 12 months (73%). Counted by Alion from the job postings of Close, updated Sep 28, 2026.
What programming languages does Close use?
Python is named in 73% of job postings at Close, followed by TypeScript (73%), JavaScript (73%), Rust (45%).
What frameworks and libraries does Close use?
Flask is named in 64% of job postings at Close, followed by FastAPI (45%), React.js (27%), Svelte (27%).
What databases does Close use?
ElasticSearch is named in 64% of job postings at Close, followed by PostgreSQL (64%), Redis (36%), Snowflake (9%).
What cloud and platforms does Close use?
AWS is named in 73% of job postings at Close, followed by GitHub (64%), Kubernetes (36%), Amazon EC2 (36%).
AWS
8 73%
GitHub
7 64%
Kubernetes
4 36%
Amazon EC2
4 36%
Amazon EKS
4 36%
Figma
3 27%
Twilio
2 18%
Apache Kafka
2 18%
Show all (16)
What developer tools does Close use?
Ansible is named in 36% of job postings at Close, followed by Docker (36%), GraphQL (36%), Rest API (36%).
Ansible
4 36%
Docker
4 36%
GraphQL
4 36%
Rest API
4 36%
Terraform
4 36%
WebSockets
4 36%
WebRTC
4 36%
Claude Code
3 27%
Show all (14)
What AI and ML technologies does Close use?
LLM is named in 55% of job postings at Close, followed by Claude (36%), ChatGPT (9%).
Which engineering practices does Close ask for?
AI Agents is named in 45% of job postings at Close, followed by CI/CD (36%), CSS Modules (27%), RAG (18%).
AI Agents
5 45%
CI/CD
4 36%
CSS Modules
3 27%
RAG
2 18%
Fine-tuning
1 9%
Show all (11)
What does each Close team work with?
The technologies each team's postings require most often, with the number of postings that require them.
Backend
5 postingsFrontend
4 postingsHow does your stack fit Close?
How is the Close stack changing?
Read from the dates of the postings themselves: a technology is new when the first posting that names it appeared in the last six months, rising or falling when its share of postings moved between the last two quarters.
How modern is the Close stack?
Close scores 88 out of 100 (Cutting-edge). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 3; legacy ones: 0.
How common is the Close stack in its industry?
Share of the 130 companies in the same industries, whose stack Alion knows, that use each technology.
What sets Close apart
Companies with a stack like Close
Questions about the Close tech stack
What programming languages does Close use?
The languages named in Close job postings are Python (73%), TypeScript (73%), JavaScript (73%), Rust (45%), Go (36%), as a share of the 11 postings of the last 12 months.
Does Close use Flask?
Yes. Flask is named in 7 of 11 job postings (64%) and required in 7 of them.
What cloud and platforms does Close use?
The cloud and platforms named in Close job postings are AWS (8), GitHub (7), Kubernetes (4) (postings in brackets).
What skills do you need for a Backend job at Close?
Backend postings at Close most often require JavaScript (5), Python (5), Rust (5), TypeScript (5), out of 5 postings in the last 12 months.
Is the Close tech stack changing?
Yes. Apache Kafka, RAG first appeared in Close job postings in the last six months.
How modern is the Close tech stack?
Close scores 88 out of 100 (Cutting-edge). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 3; legacy ones: 0.
How does Alion know the Close tech stack?
Alion reads every job posting Close publishes and tags the technologies each one names. The figures on this page count the 11 postings of the last 12 months and were updated on Sep 28, 2026.
Method and citation
Alion reads every job posting the company publishes and tags the technologies each one names. Shares count the postings of the last 12 months, open and closed; the company's own products are counted apart. How we count
Alion, "Close tech stack: 62 technologies from 11 job postings", as of Sep 28, 2026. https://alion.io/company/close/technologies